Morus alba L. (SS), Ulmus pumila L. (BY), Salix matsudana Koidz (LS), Populus tomentosa (YS), Sophora japonica Linn (GH) and Platycladus orientalis (L.) Franco (CB) was pyrolyzed at 300 °C, 500 °C, 700 °C to obtain different types of biochar, coded as SSB300, SSB500, SSB700, BYB300, etc., which were tested for their Cr (VI) adsorption capacity. The results demonstrated that the removal efficiency of Cr by biochar pyrolyzed from multiple raw materials at different temperatures was variable, and the pH had a great influence on the adsorption capacity and removal efficiency. GHB700 had the best removal efficiency (89.44%) at a pH of 2 of the solution containing Cr (VI). The pseudo second-order kinetics model showed that Cr (VI) adsorption by biochar was chemisorption. The Langmuir model showed that the adsorption capacity of SSB300 was the largest (51.39 mg·g−1), BYB500 was 40.91 mg·g−1, GHB700, CBB700, LSB700, YSB700 were 36.85 mg·g−1, 36.54 mg·g−1, 34.53 mg·g−1 and 32.66 mg·g−1, respectively. This research, for the first time, used a variety of garden wastes to prepare biochar, and explored the corresponding raw material and pyrolysis temperature for the treatment of Cr (VI). It is hoped to provide a theoretical basis for the research and utilization of garden wastes and the production and application of biochar.Garden waste is one of the main components of urban solid waste which affects the urban environment. In this study, garden waste of  Urban gardens play an important role in purifying the atmosphere, reducing noise and dust, and reducing the heat island effect ,2. HowevMorus alba L (SS), Ulmus pumila L. (BY), Salix matsudana Koidz (LS), Populus tomentosa (YS), Sophora japonica Linn (GH) and Platycladus orientalis (L.) Franco (CB) were collected at the ecological restoration experimental base  of the Environmental Protection Institute of Light Industry, Beijing Academy of Science and Technology. The branches were cleaned from dust and dried at 65 °C until constant weight. Then, the branches were cut into small sections and placed in a crucible, wrapped with tin foil to reduce air entry. The crucible was placed in a muffle furnace for the pyrolysis. The heating rate was 10 °C·min−1, the holding time was 60 min, and the reaction temperature of slow pyrolysis is generally within 1000 °C [Morus alba L. biochar , Ulmus pumila L. biochar , Populus tomentosa biochar , Sophora japonica Linn biochar , Platycladus orientalis (L.) Franco biochar , Salix matsudana Koidz biochar  were obtained at three temperatures, and stored in the dryer for use.The branches of −1, the addition of Cr (VI) solution was 25 mL, the speed of the shaking table was 250 r·min−1 and the temperature 25 ± 2 °C. In the adsorption experiments with different initial pH values, the initial pH value was blended by 0.2 M NaOH and HCL solution, the biochar was weighed in a centrifuge tube, and 50 mg·L−1 Cr (VI) solution with pH values of 2.0, 4.0, 6.0, 8.0 and 10.0 was added. The reaction was carried out in a shaking table for 1440 min. In the adsorption experiment of different reaction time, biochar was weighed in the centrifuge tube, 50 mg·L−1 Cr(VI) solution with initial pH value of 2.0 was added, and the reaction time was set as 0, 5, 10, 30, 60, 120, 360, 720, 1440 min. In other adsorption studies, the initial Cr (VI) concentration was generally set at 5–800 mg·L−1 [−1 in the adsorption experiment of different initial Cr (VI) concentrations. Biochar was weighed in a centrifuge tube, Cr (VI) solutions with pH value of 2.0 and concentrations of 5, 10, 25, 50, 100, 200 and 400 mg·L−1 were added, and the reaction time was 1440 min. After the reaction, 0.45 μm nylon membrane was used for filtration. The concentration of Cr (VI) and total Cr were detected by a UV spectrophotometer and ICP-OES. Three replicates were made for each treatment [All the experiments were carried out in a 50 mL polypropylene centrifuge tube, the addition of biochar was 1.2 g·Lreatment .−1) of biochar on Cr (VI) are calculated as follows:C0 and Ce are the initial and equilibrium concentrations of Cr (VI) (mg·L−1), V is the volume of solution (L), and m is the amount of biochar added (g). The removal efficiency  and adsorption capacity , mq is the maximum adsorption capacity (mg·g−1), Ce is the solution concentration at equilibrium (mg·L−1), n is the Freundlich equilibrium parameter, and k is the Langmuir equilibrium parameter (L·mg−1), indicating the adsorption strength, which is related to the properties of the adsorption system and usually greater than 1, n determines the shape of the isotherm. It is generally believed that 0.1 < 1/n < 0.5 is easy to adsorb, and 1/n > 2 is difficult to adsorb. FK is the adsorption capacity (mg·g−1). Using FK and n, the characteristics of different adsorbents can be compared.Freundlich model: The kinetic model uses pseudo first-order and pseudo second-order kinetic models:Pseudo first-order kinetic model:t (min) is the adsorption time, tq is the adsorption capacity at time t (mg·g−1), eq is the adsorption capacity at equilibrium (mg·g−1), K1 (min−1) and K2 (g·mg−1·h−1) are the rate constants for the pseudo first-order and pseudo second-order kinetics, respectively.Pseudo second-order kinetic model:4− form in acidic solution, but it is CrO42− in alkaline solution [42− was higher than that of HCrO4− [4− was more likely to generate electrostatic attraction between the protonated biochar surface and the positively charged biochar surface [− ions gradually increased, and the Cr (VI) morphology changed from HCrO4− to CrO42− [42− and more OH− ions, because deprotonation makes the surface of biochar negatively charged [4− has higher redox potential than CrO42− [4− was higher than that of CrO42−, so the reduction removal ability of biochar for CrO42− was lower than that of HCrO4−, so the removal efficiency of Cr (VI) was higher under acidic conditions.As we all know, the pH value is one of the important factors that affects the adsorption process. Actually, it is a key factor to determine the adsorption capacity of biochar for metal ions, especially for biochar containing amino functional groups, which are easily protonated or deprotonated, thus forming different surface charges in solutions with different pH values ,15. The solution ,17. The f HCrO4− . Therefo surface . The pH o CrO42− . This le charged ; in the  charged ,22, HCrOn CrO42− . The resThe removal efficiency results of different types of biochar can be seen from 2 calculated by Langmuir is greater than that calculated by Freundlich, which indicated that Langmuir can better explain the adsorption process of Cr (VI) on biochar prepared from different raw materials and temperatures. In general, the adsorption of Cr (VI) on biochar, in this study, belongs to chemical adsorption, which is a typical monolayer adsorption with uniform adsorption position. According to research reports, if the value of 1/n fitted by the Freundlich isotherm model is less than 1.0, the adsorption process is favorable; if the value of 1/n is greater than 1.0, the adsorption process is unfavorable [As an important indicator of adsorption, the adsorption capacity of biochar was calculated by the Freundlich and Langmuir isotherm models . The Lanavorable ,27. The −1, 40.91 mg g−1, 36.85 mg g−1, 36.54 mg·g−1, 34.53 mg·g−1, 32.66 mg·g−1, 26.34 mg·g−1, 25.96 mg·g−1, 20.04 mg·g−1, 16.18 mg g−1, 16.00 mg·g−1, 14.24 mg·g−1, 14.12 mg·g−1, 12.47 mg·g−1, 12.28 mg·g−1, 12.08 mg·g−1, 10.16 mg·g−1, 9.58 mg·g−1). It shows that the temperature of biochar had a great effect on the treatment of Cr (VI) pollution. The maximum adsorption capacity of Cr (VI) on different biochar types can also be obtained by the Langmuir isotherm model , the ads−1, SSB700, GHB700, LSB700, BYB500 and YSB700 can remove more than 90% or more Cr (VI). With the increase of the initial Cr (VI) concentration from 50 mg·L−1 to 400 mg·L−1, the removal efficiency of Cr (VI) decreased gradually, including 18.77% for SSB700, 16.73% for GHB700, 18.28% for BYB500, and 15.63% for YSB700. The removal efficiency of Cr (VI) decreased with the increase of initial concentration, probably due to the restricted number of active binding sites and newly formed thick layer on biochar [−1, the adsorption site on the surface of biochar was saturated and could not be further adsorbed to remove Cr (VI), leading to a decrease in the amount of Cr (VI) diffusion to the surface of biochar in the solution [e) of biochar on Cr (VI) increased with the increase of initial Cr (VI) concentration  had increased dramatically, after that, when the Cr (VI) concentration increased from 100 to 400 mg·L−1, within the scope of the biochar adsorption quantity growth slowed, probably because the number of active sites available on biochar was limited, thus, it could not meet the increased number of Cr (VI) ions.The initial concentration had a great influence on the removal of Cr (VI) by biochar . When thsolution . In addintration . This wae–qt) as the driving force for the adsorption reaction [2 indicates that the pseudo second-order model is superior to the pseudo first-order model. Therefore, the most likely mechanism for the removal of Cr (VI) is chemisorption [The pseudo first-order and pseudo second-order kinetic models were similar in that they all consider the difference between the equilibrium adsorption capacity and the adsorption capacity at time t  concentration in the solution within a certain period of time is shown in The results showed that the biochar prepared from different garden wastes can effectively remove Cr (VI) under acidic conditions. The Cr (VI) removal process in aqueous waste was highly dependent on pH, and the highest removal efficiency was observed at pH 2.0. The pseudo-second-order kinetic model was the optimum model for Cr (VI) removal, the reaction belongs to the chemical adsorption, Cr was not uniformly distributed on biochar. The Langmuir isotherm model was the best model for Cr (VI) removal. It showed that using biochar to remove Cr (VI) followed electrostatic attraction, Cr (VI) to Cr (III) and the rule of the complexation. The garden waste biochar used in this study exhibited a comparable or relatively slower removal rate of Cr (VI) compared to commercial activated carbon; however, the effective Cr (VI) removal and relatively lower cost of biochar make it a sustainable remedial medium for large-scale applications. In general, SSB300, BYB500, GHB700, LSB700, YSB700, CBB700 were promising adsorbents for the treatment of Cr (VI) pollution in acidic wastewater.


Additionally, molecular docking reveals that the lowest binding energy was −10.8 Kcal/mol which indicates that the L3 complex may be further studied for its biological applications.Here, we report a facile route to the synthesizing of a new donor–acceptor complex, L3, using 4-{[(anthracen-9-yl)meth-yl] amino}-benzoic acid, L2, as donor moiety with anthraquinone as an acceptor moiety. The formation of donor–acceptor complex L3 was facilitated via H-bonding and characterized by single-crystal X-ray diffraction. The X-ray diffraction results confirmed the synthesized donor–acceptor complex L3 crystal belongs to the triclinic system possessing the P-1 space group. The complex L3 was also characterized by other spectral techniques, viz., FTIR and UV absorption spectroscopy, which confirmed the formation of new bonds between donor L2 moiety and acceptor anthraquinone molecule. The crystallinity and thermal stability of the newly synthesized complex L3 was confirmed by powdered XRD and TGA analysis and theoretical studies; Hirshfeld surface analysis was performed to define the type of interactions occurring in the complex L3. Interestingly, theoretical results were successfully corroborated with experimental results of FTIR and UV absorption. The density functional theory (DFT) calculations were employed for HOMO to LUMO; the energy gap (∆E) was calculated to be 3.6463 eV. The complex L3 was employed as a photocatalyst for the degradation of MB dye and was found to be quite efficient. The results showed MB dye degraded about 90% in 200 min and followed the pseudo-first-order kinetic with rate constant k = 0.0111 min In recent years, several attempts have been made regarding the synthesis of charge transfer (CT) complexes due to their structural applications in different branches of chemistry including organic semiconductors ,2, photoMethylene blue (MB) is a basic dye that is widely utilized in different industries, viz., coloring paper, dyeing cotton and wools, leather, etc. . Direct All the materials used were of high grade without further purification. 4-amino benzoic acid, 9-anthracenecarboxaldehyde and anthraquinone were purchased from Sigma Aldrich  and used as such. The solvent used was ethanol  used as such and purchased from Fisher Scientific, Bangalore, India.−1 by using KBr pellets. A Thermo Scientific Evolution 201 UV–Vis spectrophotometer  was used for the absorption spectrophotometric measurements of both L2 and L3. The samples were prepared in 10−4 M concentration in a cuvette of 1 cm path length with ethanol as solvent. The PXRD pattern of the CT complex (L3) was recorded using the Miniflexll X-ray Diffractometer  with Cu-Kα radiation scan in the range of 4 to 80 . The Thermogravimetric analysis (TGA) curve was recorded on a Shimadzu TGA-50H instrument  under nitrogen atmosphere at a heating rate of 20 °C min−1.The IR spectra of the synthesized complex were measured on Thermo Scientific iS50-FTIR spectrophotometer  in the range from 4000 to 400 cm58H41N2O6 (861.98) was C, 80.82; H, 4.79; N, 3.25%; the found percentages were C, 79.92; H, 4.25; N, 3.09%.The ligand (L2) was synthesized by an earlier reported procedure . Both li0 is the initial concentration of dye at time t = 0, while Ct represents dye concentration at time t = t, a plot between ln(C0/Ct) vs. time intervals gives a straight line with slope k  moiety of complex L3 and the weak interaction with dye was responsible for efficient degradation. There were five different intermolecular attractions, viz., H…N, H…O, H…H, H…C and C…C (π–π), which were responsible for stabilization and fetch of charge between complex L3, as confirmed by 2D fingerprint plots of Hirshfeld surfaces analysis [+ dye facilitated the interaction between nucleophilic aromatic rings of anthraquinone of the L3 complex and propagated the dye-degradation reaction, which diminished the changes of recombination of charges and enhanced the efficiency of the reaction [Finally, these highly active oxidizing species, i.e., analysis . The antreaction ,34.•OH radicals, which can break the MB dye. The electrons in the CB, on the other hand, combine with the molecular oxygen superoxide radical that is highly reactive and degrades the organic dye substantially. Less band-gap energy is attributed to photocatalytic efficiency with easier electron promotion from VB to CB, resulting in a higher number of holes being formed in the VB, which are accountable for greater numbers of •OH radicals being produced in their VBs. The higher the number of electrons in the CB, the more superoxide radicals are generated. As previously described in the literature, the •O2− and •OH radicals are responsible for organic pollutant photodegradation in substances such as MB dye [Using band-structure calculations, we can easily explain the photocatalytic activity involved with L3. We plotted DOS and p-DOS graphs of L3 with the help of DFT calculations . The ress MB dye .−1, respectively [Important vibrational modes of the L3 complex were measured via FT-IR  and compared to the theoretically calculated wavenumbers. The experimental spectra were obtained in solid form, whereas theoretically calculated vibrational frequencies were estimated in isolated molecules in the gaseous phase. DFT calculated wavenumbers illustrated discrepancies revised by utilizing the scaling factors 0.961 and 0.96, below and above 3000 cmectively . The abs−1. In the phenyl ring, C–H stretching seemed like a pure mode. In the FT-IR spectra, the equivalent experimental mode was observed at 3110 and 2852 cm−1. The ring C–C stretching appeared in a range of 1625 to 1430 cm−1. At 1580 cm−1, a very sharp band was detected, which was compatible with C–C stretching. The aromatic ring’s C–C bending in-plane occurred as mixed modes with the C–H in-plane bending vibration.The stretching vibrations, such as C–H, C–C, and C=C, could be seen in the phenyl ring spectra, as well as different bending vibrations, such as C–C–C, H–C–H and C–C–H. The aromatic ring’s C–H stretching ranged from 3000 to 3150 cm−1, depending on conjugation, hydrogen bonding, and the size of the ring to which it was attached. Carbonyl groups’ bending modes are likely to be weak and observed as mixed modes. For C=O stretching, FT-IR vibrations were found at 1750 and 1601 cm−1. An OH vibrational mode was found at 3490 cm−1 and 3351 cm−1 experimentally.A carbonyl group is a polar multiple-bonded group established by p–p bonding between carbon and oxygen. The difference in electro-negativities causes electrons to move towards oxygen, resulting in the carbonyl group. The carbonyl group’s nature is determined by the lone pair of oxygen . In L3, −1 for single bonds. Because the L3 complex has only one NH group, the peak emerged at 3433 cm−1. Bending NH vibrational modes were found as mixed-mode vibrations at roughly 1600 cm−1 due to nitrogen–carbon bond stretching and bending of the N–H bond at 1427 cm−1 at lower frequencies, i.e., 1641–1085 cm−1.N–H stretching peaks arise at 3300–3500 cm−2, −6.497 × 10−2 and −4.31 × 10−2, showed in the figure by a red shade and called an electrophilic region. A nucleophilic area was defined as a positive range of +5.923 × 10−2, +6.497 × 10−2 and +4.31 × 10−2, which was represented by a blue tint. The electrostatic potential is modest, as evidenced by the little yellow tint between the phenyl rings. The light blue area (MEP of L3) in between L2 and anthraquinone shows the transfer of electrons from donor to acceptor.α), hyperpolarizability (β) and dipole moment (µ) of L3, an isolated molecule in the gas phase of L3 was used [xxα, xyα, yyα, xzα, yzα, zzα and xxxβ, xxyβ, xyyβ, yyyβ, xxzβ, xyzβ, yyzβ, xzzβ, yzzβ, zzzβ) from the Gaussian frequency output file were used. To begin, the units were converted to e.s.u  [α) and the mean value of initial hyperpolarizability (β) were calculated using the equations below.To determine NLO properties in terms of the calculated polarizability (was used . DFT wit e.s.u.) . The dipα) and hyperpolarizability (β) the following equations were used:For analyzing polarizability  basis set, which included PCM (polarizable continuum solvation model) with ethanol . Values eristics .−4 M concentration using polar organic solvent ethanol. The λmax of L2 and L3 were found to be 243.5 nm and 252 nm, respectively 2 vs. hν can be found in The following equation was applied to calculate band-gap energy of synthesized materials:norm, di, de, shape index, curvedness and fragment patch, respectively. The distance between the atoms existing in the crystal system is described by the di and de pair’s sum. Lists of all 3D surfaces with their lowest, maximum, and mean values, as well as their dnorm, di, de, shape index, curvedness and fragment values are given in Interactions between atoms in the crystal of L3 were investigated using Hirshfeld surface analysis. norm value ranged from −0.787 to 2.364 Å, the shape index ranged from −0.995 to 0.998 Å, and the curvedness ranged from −3.625 to 0.397 Å, as shown in norm surface has brick red circular patches, representing close interaction with surrounding molecules; a hydrogen connection between O–H and N–H was discovered despite the fact that the intermolecular H–H, N–H, C–H and S–H interactions are defined by blue and white patches. Because the O atom has a greater electronegativity (3.34) than the N atom (3.04), it is possible that the oxygen atom influenced the electron density on the H atom the most. One of the key characteristics of Hirshfeld analysis is the shape index, which identifies complementarity between molecules in crystal packing [In L3, the d packing . Patchesnorm Figures, along with the proportion of intermolecular contacts provided by each atom are available in Curvature is used to determine the surface area of a molecule’s shape . The eleThese 2D plots revealed small spikes, such as a pseudo-symmetrical region with a high concentration of blue color, that encircled the entire area contributed . Almost The TONTO program , which iMolecular docking  is the mHerein, we report a novel donor–acceptor complex, L3, synthesized using anthraquinone and our own synthesized ligand (L2) via reflux method. The synthesized complex (L3) was characterized through different techniques including SCXRD, FTIR, electronic spectroscopy, PXRD and TGA. The SCXRD results revealed that the formation of new L3 complex occurred via H-bonding between the donor (L2) and acceptor moiety (anthraquinone). We also performed theoretical studies including Hirshfeld surface analysis and DFT/TD-DFT to decode the surface and short interactions. The DFT/TD-DFT calculations showed that optimized geometrical parameters, FTIR and UV spectra of L3 were in agreement with the experimental results. NLO was evaluated, and total dipole moment was observed to be 6.572 D. NLO studies suggested that the L3 complex can be considered a high quality NLO material. The frontier molecular orbitals HOMO and LUMO were located in their spatial arrangements and the energy gap (∆E) was found to be 3.6463 eV. With the help of these calculations, we successfully employed L3 as a photocatalyst in the degradation of Methylene blue (MB) dye. Almost 90% of dye was degraded in just 3.2 h. Computed results of density of state and partial density of states assisted the plausible mechanistic pathways by which L3 accomplished photodegradation. The results were promising for the use of L3 as a photocatalyst in the degradation of other dyes as well in future applications. Additionally, molecular docking revealed that the lowest binding energy was −10.8 Kcal/mol, which indicates that the L3 complex may be further studied for its medicinal applications.


Simple protein precipitation was successfully applied for sample pretreatment. The HCQ displays a good linearity in the range of 2.0–5000.0 ng/mL, and the three metabolites also show good linearity ranging from 1.0 to 2500.0 ng/mL, with all correlation coefficients (R2) better than 0.98. In conclusion, this rapid, sensitive method was successfully developed, validated, and then applied to a pharmacokinetic study of HCQ in rat model in high dose. The results of the pharmacokinetic study presented an average half-life time 21.14 ± 10.31 h (mean ± SD) of HCQ, which is much shorter in human compared to that in mice. For the three metabolites, longer half-life times (approximately 100 h) were shown in rat.Hydroxychloroquine (HCQ) was originally used as an antimalarial and immunomodulation drug. We developed and validated a simple and sensitive ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for simultaneous quantitation of HCQ and its three metabolites in rat blood, and reported their pharmacokinetic parameters. The chromatographic separation and detection of analytes were achieved within 4 min on ZORBAX SB-C Hydroxychloroquine (HCQ), an antimalarial drug, is the hydroxyl-substituted product of chloroquine (CQ), which has become the backstone in the treatment of rheumatic arthritis (RA) and systemic lupus erythematosus (SLE) in recent years because of its characteristics of immunomodulatory, hypolipidemic, antithrombotic effect, and, furthermore, the HCQ was utilized to reduce the risk of malignant tumors and treat sarcoidosis and still disease .in vitro studies had confirmed that HCQ and CQ have antiviral activity against SARS-CoV-2 virus and that the efficacy of HCQ is better than that of CQ , but many clinical studies had reported that HCQ was ineffective in human body for Covid-19 [Cmax was 44.1 ± 27.6 ng/mL (mean ± SD), tmax was 3.85 ± 1.04 h, AUC0–60 was 1789 ± 383 ng h/mL, and t1/2 was about 298 ± 105 h. The HCQ showed an extremely slow elimination in human [t1/2 12.7 ± 1.1 h, AUC0–∞ 5577.8 ± 881.8 ng h/mL, and AUC0–72 5490.6 ± 890.0 ng h/mL. The half-life time of HCQ in mice is much shorter than that in human. These results make the therapeutic drug monitoring and pharmacokinetic study of high-dose HCQ necessary.Recent Covid-19 . In thesCovid-19  in the lCovid-19 . In a stin human . In compin human . reporteSome studies have reported several methods about quantification of the HCQ and its metabolites based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) in recent 5 years, and their applications in quantifying the HCQ and its metabolites in human blood and mouse blood and tissues , 13–16. The standards including BDCQ (Lot: 7-MJC-76-1), DCQ (Lot: 3-NZZ-137-6), DHCQ (Lot: 6-MR-3-1), and HCQ (Lot: X11J11G109865) were purchased from Toronto Research Chemicals . HCQ-d4 (Lot: ZZS-20-040-B5) was used as the internal standard (IS) for all the analytes and supplied by Shanghai Zhenzhun Biotechnology Co., Ltd. . HPLC-grade methanol (MeOH) was obtained from Merck . HPLC-grade formic acid (FA) and ammonium acetate were purchased from Tedia Company Inc. . Double-distilled water was obtained from the A.S. Watson Group  Ltd. and was used throughout. All other reagents used in the study were procured from qualified chemicals suppliers and of analytical grade. Blank blood was collected with heparin-anticoagulation in employing rat as an experimental model in the Animal Experiment Center of Shanghai University , and stored at −80°C until use.An Agilent 1290 ultrahigh performance liquid chromatography coupled to 6460A mass spectrometer, which was equipped with a binary pump (G4220A), online degasser (G1969-80230), an autosampler (G4226A), and column oven (G1316C), was used in our study . All data were acquired and processed using Agilent Masshunter data processing software .8 column  at a flow rate of 0.25 mL/min with column temperature set at 40°C. The mobile phase A was 0.2% FA plus 10 mmol/L ammonium acetate in water, and mobile phase B was MeOH. The initial mobile phase consisted 95% of phase A and 5% phase B. Gradient variation was as follows: 0–1 min, 95% phase A; 1–1.1 min 95% ⟶ 5% phase A; and maintained 5% phase A until 4 min. The injection volume of sample was 5 μL with a 10-second needle wash using 75% MeOH aqueous solution.The chromatographic separation of four analytes was achieved based on a ZORBAX SB-CThe mass spectrometry detection was achieved on an Agilent 6460A mass spectrometer equipped with Agilent jet stream electrospray ionization (AJS-ESI) source. Data acquisition was operated in the multiple reaction monitoring (MRM) mode. The optimized mass spectrometer source settings were utilized: capillary voltage 4500 V, sheath gas temperature 400°C, sheath gas flow 12 L/min, nebulizer pressure 45 psi, dry gas temperature 320°C, and dry gas flow 10 L/min. All analytes were detected in positive ionization mode. The optimized MRM parameters for HCQ and its three metabolites are shown in μL of combined working solutions was added to 475 μL rat blood to obtain the calibration standards at 2.0, 5.0, 10.0, 20.0, 50.0, 100.0, 200.0, 500.0, 1000.0, 2000.0, 4000.0, and 5000.0 ng/mL for HCQ; 1.0, 2.5, 5.0, 10.0, 25.0, 50.0, 100.0, 250.0, 500.0, 1000.0, 2000.0, and 2500.0 ng/mL for BDCQ, DCQ, and DHCQ. QCs were separately weighed and prepared using the same way at three different concentration levels including the low quality control (LQC) (5.0 ng/mL for HCQ and 2.5 ng/mL for three metabolites), middle quality control (MQC) (2000.0 ng/mL for HCQ and 1000.0 ng/mL for three metabolites), and high quality control (4000 ng/mL for HCQ and 2000.0 ng/mL for three metabolites).The stock solutions of HCQ and its metabolites BDCQ, DCQ, DHCQ as well as the IS HCQ-d4 were individually prepared in MeOH aqueous solution , and 2.01, 2.01, 2.02, 2.00, 2.01, and 1.0 mg of HCQ, BDCQ, DCQ, DHCQ, and HCQ-d4 were accurately weighed and prepared, respectively. The final concentrations of five stock solutions were all at 1.0 mg/mL. All stock solutions were aliquoted and stored at −80°C. The stock solutions of all analytes were further diluted with 10% MeOH and combined to prepare the calibration standards and quality control samples (QCs), and 25 μL sample was transferred into a 1.5 mL polypropylene tube and spiked with 200 μL of acetonitrile (containing 100 ng/mL HCQ-d4). The mixture was vigorously vortex mixed for 3 minutes prior to centrifugation at 14500 × g for 10 min at room temperature, and 5 μL of the supernatant was injected directly into the LC-MS/MS system for analysis.For the blood sample, the pretreatment was performed based on one-step protein precipitation. Briefly, 50 This newly developed LC-MS/MS method was fully validated according to the guidance of FDA and Chinese Pharmacopoeia (the 2015 edition).Method validation, including selectivity, matrix effect and recovery, linearity, interday and intraday precision and accuracy, and stability, was carried out using the same way reported before , 18.The protocol of the animal study was approved by the Experimental Animal Ethics Committee of the Naval Medical University. Healthy male SD (Sprague–Dawley) rats, 200–220 g, were obtained from the animal experiment center of Shanghai University and were fed with standard food and water for 1 week before the experiment. Pharmacokinetic study of HCQ was conducted in rats after an overnight food fasting (12 h) with free access to water. The animal study was carried out in accordance with the National Institutes of Health Guide for the Care and Use of Laboratory animals.μL of blood was collected at 0, 0.083, 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 12, 24, 48, 72, and 96  h into heparin sodium-pretreated tubes. The samples were gently mixed and then stored at −80°C until analysis.In this study, SD rats were dosed with 36 mg/kg HCQ intragastrically. The dose of HCQ in this experiment was calculated according to HCQ concentrations in a longitudinal cohort analysis of SLE  and a HCC2 for all analytes.The pharmacokinetic parameters of HCQ and its three metabolites in blood were calculated using a noncompartmental model with Drug and Statistics (DAS) software . The weighing factor was designated as 1/18 , Agilent ZORBAX SB-C8 , Waters Xbridge®HILIC , Waters Atlantis T3 , Agilent Eclipse XDB-C18 , Waters Xbridge C18, Waters XSELECT CSH C18 , and some other analytical columns. It was found that the HCQ and metabolites were well retained and separated on the Agilent ZORBAX SB-C8 column, and the analytical time was relatively shorter among all the tested columns. Second, the effects of different mobile phases and additives were investigated, and different concentrations of FA, ammonium acetate and their mixed solutions in MeOH, acetonitrile or/and water, and acidified MeOH and acetonitrile were tried successively. When FA or ammonium acetate aqueous solution was used alone, the chromatographic peak shape was seriously tailing. Acidified MeOH or acetonitrile could not further improve the peak shape and a poor retention was shown. According to the principle of simplicity and rapidity, 0.2% FA plus 10 mmol ammonium acetate aqueous solution (phase A) and MeOH (phase B) were finally chosen as the optimal mobile phases. Lastly, the gradient elution procedure and the mass spectrometry detection parameters such as collision energy, fragmentor energy, nebulizer pressure, and drying gas were optimized. Combined with C8 column, all the analytes presented symmetrical peak shape and appropriate retention time. To obtain the optimal peak resolution, reproducibility and shorter chromatographic separation time, lots of chromatographic conditions, including different analytical columns, mobile phases, and elution procedures, were tested in the method development process. First, the effects of different chromatographic columns on the retention and separation of four analytes compounds were investigated. We tested Agilent ZORBAX SB-CμL acetonitrile was used to eliminate the possible interferences in 100 μL blood sample by protein precipitation, and the highest (>86%) and consistent extraction recovery of all the analyte was achieved. Compared with solid phase extraction and liquid-liquid extraction, this protein precipitation method is fast, simple, and economical.Matrix interferents removement is the critical step in the pretreatment of biological samples, which is the base of high and stable recovery and matrix effect. In the pretreatment method development, we tested a variety of methods to remove proteins and other potential interfering substances in blood. The most common biological sample pretreatment methods are protein precipitation, liquid-liquid extraction, and solid phase extraction . In the In order to evaluate the selectivity, we compared the responses from blank, IS spiked, and real samples , and theThe evaluation of matrix effects in biological samples for quantitative analysis of drugs by mass spectrometry is an important aspect of method validation . The ranχ2. The linear correlation coefficients of all analytes are greater than 0.98. The typical regression equations of the standard curve are shown in The calibration curve was constructed by calculating the peak area ratio  of the calibration standards to the measured concentrations. Twelve calibration standards were obtained from the spiked samples, and the best linear and least square residuals were obtained when the weighing factor was 1/The QC samples in four concentration levels  and LLOQ samples were assessed in five replicates at three separate analytical lots to determine the intraday and interday precision and accuracy. The results of interdayand intraday precision and accuracy are acceptable and are summarized in We investigated the stability of four analytes in rat blood at two concentration levels (low and high). As a consequence, the analytes were steady in autosampler for 24 h with deviations located within ±15% (RE%). After being stored at −80°C for 30 days, there are no significant deviations in QC samples. Meanwhile, no obvious deviations were found after three freeze-thaw cycles. Bench-top stability also presented deviations within ±15% (data not shown). All the results are shown in Cmax of HCQ in rats was 1440.72 ± 298.24 μg/L (mean ± SD) and T1/2 was 21.14 ± 10.31 h. AUC0–∞ was 42774.94 ± 8495.26 μg/L∗h, and the clearance rate was 1.52 ± 0.38 L/h/kg. The pharmacokinetic parameters of HCQ in rats were compared with that in mice reported in literature, and the blood elimination T1/2 and AUC0–∞ were similar to that in mice, while the Cmax in rats was 40 times higher than that of mice and these results may be attributed largely to a higher administration dose [T1/2 of HCQ was much longer and Cmax of HCQ in rats was approximately 30 times higher than that in human [Cmax values than the DCQ and BDCQ. In a study, the association of gene polymorphisms of CYP 2D6 and blood HCQ level was assessed in SLE patients, and the results showed that the CYP 2D6 polymorphism was significantly associated with the DHCQ/HCQ ratio, and this may explain why there is a wide variation of HCQ concentration [An UHPLC-MS/MS method was established and validated for determining HCQ and its three metabolites, which was then applied to a pharmacokinetic study of HCQ. HCQ (36 mg/kg) was given to rats by intragastric administration. The blood concentration-time curves of HCQ and its three metabolites are shown in ion dose . In humain human , and theP < 0.001) while the BDCQ was believed to be associated with the ocular adverse events (P=0.036) [P=0.007) [The in vivo exposure of drug had a close relationship with the therapeutic results, and concentrations located in the therapeutic window can obviously increase the responses and decrease the adverse reactions. A study investigated the concentration-response relationship of HCQ in the treatment of RA, and different doses  were prescribed and the blood exposure of HCQ was proven to be positively associated with the gastrointestinal adverse events, in addition, the blood concentration of DHCQ had a positive correlation with response in RA patients (P=0.036) , and thiP=0.007) . These rA simple, rapid, sensitive, and reproducible UHPLC-MS/MS method was developed and validated in this study, which was suitable for simultaneous determination of HCQ and its three metabolites  in rat blood. After optimizing the chromatographic separation and mass spectrometry detection conditions, a shorter analytical time (4 min) and lower LLOQ (approximately 1.0 ng/mL) for all analytes were achieved. In addition, the pharmacokinetic parameters of high-dose HCQ and its three metabolites in rats were firstly reported in this study. The metabolic pattern of HCQ is comparable to that in mouse and is significantly different from that in human.


Eosinophilic esophagitis (EoE) has emerged from a case‐reportable illness in the early 1990s to a distinct clinicopathological entity. Increasing worldwide incidences have been observed, although due to various study designs estimates are inconsistent.To determine population‐based annual incidence rates over a time period of 25 years.A nationwide register‐based pathology (PALGA) search was performed to identify reports describing esophageal eosinophilia between 1995 and 2019. EoE was identified if the diagnosis was confirmed by the pathologist. Crude incidence rates were estimated by the number of new EoE cases per year and matched with population data.p < 0.001) and adults . Highest incidences were observed in 2019, being 4.37 (95% CI: 3.94 – 4.84) vs. 1.97 (95% CI: 1.68 – 2.29) per 100.000 males and females, respectively (p < 0.001). No seasonal variation was observed.Between 1995 and 2019, 7361 unique patients’ reports mentioned esophageal eosinophilia, of these 4061 were classified as EoE . In total, 639 (16%) children (<18 years) were diagnosed. The EoE incidence increased from 0.01 in 1995 (95% CI: 0.0 – 0.04) to 3.16 (95% CI: 2.90 – 3.44) per 100.000 inhabitants in 2019. EoE was significantly more prevalent in males (OR 2.48 | 95% CI: 2.32 – 2.65; vs. females Over the past quarter century, the annual rates of newly diagnosed EoE patients raised dramatically and this increase has not reached a deceleration yet. Xxxxxx CIconfidence intervalsEGDesophagogastroduodenoscopyEoEeosinophilic esophagitiseoseosinophilsGERDgastroesophageal reflux diseaseGIgastrointestinalhpfhigh‐power fieldORodds ratioPPIproton‐pump inhibitorTh2T‐helper type 21Eosinophilic esophagitis (EoE) is a chronic immune‐mediated disease characterized by symptoms of esophageal dysfunction and infiltration of the mucosa with eosinophils.22.1This cross‐sectional study was conducted by using results from the nationwide network and registry from cyto‐ and histopathology in the Netherlands (PALGA).2.2In this follow‐up study, a similar diagnostic framework for case identification was used as was previously published by our research group.2.3To estimate the number of EGDs with esophageal biopsy sampling performed between 1995 and 2019, the PALGA database was queried. Search criteria were “esophagus” and “biopsy.” Of note, outcomes of this search yield an estimation of the total number of unique endoscopies with biopsies performed, considering that the search was not manually reviewed.2.4https://www.cbs.nl). Incidence rates were calculated for the entire population and stratified for gender and age. Descriptive statistics were used to assess demographic characteristics, presented as mean (±SD) for normally distributed continuous data and percentages (%) for categorical data. Groups were compared with chi‐square statistics and unpaired t test, as appropriate. A p‐value of 0.05 was considered to be statistically significant. Odds ratio (OR) and 95% confidence intervals (CI) were calculated by using MedCalc Software Ltd .Statistical analysis was performed by using IBM SPSS Statistics (version 25.0) . To calculate the annual incidence rates between 1995 and 2019 the total Dutch population was considered to be at risk for developing EoE. Crude incidence values were calculated by using the total number of newly diagnosed EoE patients and matched with Dutch population data , were removed. In total, 7361 unique patients, who covered a total of 9068 reports with esophageal eosinophilia, were considered to be eligible for final inclusion. After the first review, 5076 unique reports were classified as “suspected for the diagnosis of EoE.” In total, 4061 unique patients were identified with a confirmed diagnosis of EoE following a second critical appraisal based on requested clinical information with regards to the indication of performed EGD (n = 3509). Of note, 31 patients being already included in our previous search (1995–2016) with no diagnosis of EoE were re‐reviewed, of which EoE was confirmed in 27 patients. In total, 3974 (98%) reports were diagnosed with EoE at the first EGD. Furthermore, 2110 patients were diagnosed with different disease entities other than EoE. A flowchart of case identification is presented in Figure 3.2p < 0.001). In children, the mean age at diagnoses was 10.9 ± 5.3 years, of which no difference between males and females  was observed. EoE was diagnosed at all ages , with patients between the ages of 20 and 49 years being mostly affected. An overview of all newly identified EoE patients within the years of 1995 and 2019, stratified by gender and age, is presented in Figure A male predominance (71%) was confirmed in our cohort, with a mean age at diagnosis of 37.9 ± 18.4 years. In total, 639 (16%) children (<18 years) and 3422 (84%) adults were diagnosed. Of all identified adult EoE patients, 2419 (71%) were male and 1003 (29%) were female. The mean age at diagnosis in adults was 42.9 ± 15.4 years, with a significant higher age in females compared with males  patients were identified with EoE and coexisting GERD, 64 (59%) patients with EoE and Barrett's esophagus, and 26 (24%) patients with EoE and esophageal candidiasis. In addition, no seasonal variations in the diagnosis of EoE were observed within the entire study timeframe Figure .3.3The degree of esophageal eosinophilia in all identified EoE patients was mentioned in 1608 (40%) unique reports, of which 1473 (36%) were classified as marked  and 135 (3%) as mild . Of note, in all 135 reports describing “mild” esophageal eosinophilia, the diagnosis of EoE was confirmed and/or ≥15 eos/hpf were described by the pathologist. In only 588 (15%) reports, the esophageal eosinophilia was quantified as ≥15 eos/hpf within the entire study time frame. Between 1995 and 2009, quantification of the esophageal eosinophilia (ie ≥15 eos/hpf) was not stated in any of the reports. Between 2010–2014 and 2015–2019, the esophageal eosinophilia was described as ≥15 eos/hpf in 124 (3%) and 464 (12%), respectively, pathology reports. Additional histological features, such as; spongiosis, micro‐abscesses, basal zone hyperplasia, and sub‐epithelial fibrosis were described in less than 2% of all pathology reports.3.4p < 0.001). Annual incidence rates of males and females between the years of 1995 and 2019 are presented in Figure p < 0.001). Trends of incidence rates in children and adults are demonstrated in Figure p < 0.001). In 2019, EoE was mostly diagnosed in patients between the ages of 20 and 29, with significantly higher rates in males compared with females of 1.83 (95% CI: 1.45–2.28) vs. 0.90 (95% CI: 0.64–1.24 new cases per 100.000 inhabitants), respectively (p < 0.001). The majority of EoE patients (55%) were identified between the years of 2015 and 2019, with an estimated annual incidence over this time period of 2.63 (95% CI: 2.4 – 2.9) new EoE cases per 100.000 inhabitants. Distribution of year of diagnosis in 5 years strata for male and female patients is presented in Figure The entire Dutch population comprised a total of 15.424.122 inhabitants in the year of 1995 and 17.282.163 inhabitants in the year of 2019 in accordance with the Central Bureau of Statistics (CBS). The average annual incidence of new cases per year during this time period is estimated to be 0.99 (95% CI: 0.84–1.15) per 100.000 inhabitants, based on the population of 16.390.837 citizens. Between the years of 1995 and 2004, the incidence rates increased slightly from 0.01 (95% CI: 0.0–0.04) new cases per 100.000 inhabitants in 1995 to 0.08 (95% CI: 0.04–0.14) new cases per 100.000 inhabitants in 2004. From then on, an impressive rise of yearly new EoE diagnosis was observed between 2005 and 2019, comprising rates of 0.14 (95% CI: 0.09–0.21) to 3.16 (95% CI: 2.90–3.44) new cases per 100.000 inhabitants. During the time period between 1995 and 2019, males were significantly more at risk for the presence of EoE compared with females  was confirmed in this large cohort and patients between the ages of 29 and 49 years were most often affected. Within the entire study period, the EoE incidence was significantly higher in adults compared to children. These findings are consistent with previous literature, and the natural course of this chronic progressive disease.Helicobacter Pylori infections and increasing prevalence of GERD in developed countries over the past several decades are both considered to contribute to the rapid rise of EoE.The ongoing rise of EoE incidences in the Netherlands is consistent with previous findings on EoE being an increasingly common disorder in developed countries.Some methodological challenges were encountered during this study. No data were available on patients’ characteristics  due to the use of encoded PALGA pathology reports. Therefore, the majority of EoE diagnosis (52%) were exclusively based on histological information. Moreover, in only 588 (15%) reports the esophageal eosinophilia was quantified as ≥15 eos/hpf by the pathologist. These limitations of our diagnostic framework may have resulted in an underestimation of the observed EoE incidences. Nevertheless, 3509 (48%) reports were re‐reviewed by using additional information with regard to the indication of performed EGD in order to expand the reliability of our case‐finding strategy. Of note, a former medical chart review  was performed by our research group, by that affirming a clinicopathological EoE diagnosis in 721 (33%) randomly selected cases between 1995 and 2015.In conclusion, we present observations on escalating EoE incidences over a considerable time frame of 25 years in the Netherlands. From these results, it is clear that EoE incidence has not stabilized yet and continues to rise. These findings underscore the need to further investigate the mechanisms underlying its pathogenesis and which dynamic environmental components could lead to such an expansion of EoE cases.WEdR, MEB, MJW, BDvR, AHB, and JV have no conflicts of interest. AJB has received research funding from Nutricia, SST, Norgine, and Bayer; and speaker and/or consulting fees from Laborie, EsoCap, Medtronic, DrFalk, Calypso, Regeneron, Celgene, Norgine, and AstraZeneca and owns stocks SST.WEdR is the guarantor of the article. WEdR, MJW, BDvR, JV, and AJB assisted in writing. WEdR, MJW, BDvR, and AJB conceived and designed the study. WEdR, MEB, MJW, BDvR, AHB, and AJB involved in generation, collection, assembly, analysis, and/or interpretation of data. WEdR prepared draft of the article. WEdR, MEB, MJW, BDvR, JV, AHB, and AJB approved the final version of the manuscript.


The experimental results indicate that the as-prepared CA–SC has a high affinity for Ca2+ and Mg2+ and can remove 96.5% of Ca2+ (or 96.8% of Mg2+) from the corresponding solution. The maximum adsorption capacities of CA–SC for Ca2+ and Mg2+ are 62.38 and 36.23 mg/g, respectively. These values are higher than those of the most reported Ca2+-sorbents and Mg2+-sorbents. The CA–SC adsorbent can be regenerated through a simple pickling step, and its adsorption performance keeps stable after repeated use. Analysis of the adsorption mechanism shows that the CA–SC combines Ca2+ and Mg2+ in water mainly through coordination effect.In this work, a novel alginate/citrate composite aerogel (CA–SC) was synthesized by chemical grafting technology combined with vacuum freeze-drying method, and CA–SC was used for removing calcium (Ca In industry, the precipitation of calcium and magnesium salts forms scale, hinders heat conduction, and even causes a boiler explosion in severe cases. Therefore, developing a new method of removing excessive Ca2+ and Mg2+ from water has important application prospects [2+ and Mg2+ removal from water mainly include precipitation [Although Caetergent . Prolongpitation , boilingpitation , use of pitation , ion excpitation , electropitation , and adspitation ,9. Amongpitation ,11.2+ and Mg2+ from water. For example, El-Nahas et al. and Xue et al. utilized nano powder zeolite and mesoporous zeolite, respectively, for Ca2+ and Mg2+ removal in water [Fusarium verticillioides fungus to soften hard water [2+ and Mg2+. However, nano-sized adsorbents usually require strict preparation conditions, such as high temperature, high pressure, and high-purity reagents [Recently, many nano-adsorbents have been developed to remove Cain water ,13. Mahmrd water . Given treagents . The hig2+ and Mg2+ in water. Alginate is a kind of natural polymer, which is often used in the treatment of heavy metal poisoning and as a drug sustained-release agent [Sodium citrate is a safe, non-toxic, water-soluble, biodegradable, and synthetic organic compound. It is often used as a flavoring agent and stabilizer in the food industry, and as an anticoagulant and a blood transfusion agent in the pharmaceutical industry ,17. In ase agent ,20,21,222+ and Mg2+ ions in water, in this study, we used green sodium alginate and sodium citrate as raw materials to prepare a new low-cost, easy-to-recover calcium alginate–sodium citrate composite aerogel (named as CA–SC). In addition, we also characterized the morphology and chemical composition of the prepared adsorbent and evaluated its abilities in the treatment of water containing Ca2+ and Mg2+ ions.To effectively remove Ca−1 is an O–H stretching vibration, and the absorption peak around 2929 cm−1 belongs to the aliphatic C–H stretching vibrations [−1 can be assigned to C=O and C–O vibrations, respectively [−1 in sodium alginate and CA–SC can be assigned to C–O–C vibration. Compared with the infrared spectra of sodium alginate and sodium citrate, the new absorption peak at 1536 cm−1 in CA–SC is an N–H bond derived from the modified ethylenediamine [− peak in CA–SC has increased somewhat. Although the –COO− in alginate reacts with the –NH2 of ethylenediamine and consumes some –COO− groups, the citrate modified on CA–SC has twice the –COO− groups, which leads to an increase in –COO− content in CA–SC [The functional groups in the adsorbent were verified via spectroscopic characterization of sodium citrate, sodium alginate, and CA–SC. As shown in brations . The peaectively . The absediamine . In addiin CA–SC .In the process of preparing CA–SC, we found that the concentration of sodium alginate and ethylenediamine had a great influence on the morphology of the final adsorbent. Therefore, different concentrations of sodium alginate and ethylenediamine were employed to prepare the CA–SC adsorbent. The results showed that as the concentration of sodium alginate increased, the shape of CA–SC obtained transformed from sheet to sphere. On another hand, when the reactant ethylenediamine remains greater, the color of CA–SC is darker. Therefore, 3.0 w/v% sodium alginate and 5.0 w/v% ethylenediamine were selected to prepare the CA–SC sorbent in this work.2+ (or Mg2+) solution of different pH , stirred for 6 h, and then filtered. The amount of remaining Ca2+ (or Mg2+) in the filtrate was determined by ICP-OES. It can be seen from 2+ and Mg2+ gradually increases and becomes stable. When the solution pH value is less than 1.0, the removal efficiency of CA–SC for Ca2+ and Mg2+ is less than 35%. This result may be attributed to the protonation of the –COO− and –NH groups on CA–SC under a strong acid environment, thereby reducing the amount of coordinated functional groups with Ca2+ and Mg2+. In addition, according to the solubility product rule, when the pH of a solution is higher than 9.78, Mg2+ in the solution begins to form Mg(OH)2 precipitation 2 precipitation). Therefore, the optimal pH range of the solution is 5.0–9.5. Within this range, precipitation is absent, and only few protonated functional groups are present.Approximately 0.1 g of CA–SC was weighed, added into 50 mL of 1.5 mM Ca2+ (or Mg2+), stirred for 10, 20, 30, 60, 120, 180, 240, 300, 360, 420, 480, or 540 min, and filtered. The amount of Ca2+ (or Mg2+) remaining in filtrate was measured using ICP-OES. As can be seen in 2+ or Mg2+ firstly increases and is kept stable. CA–SC can remove more than 80% of Ca2+ and Mg2+ in the corresponding solution with an adsorption time of 2 h, and reaches saturation with an adsorption time of 6 h. Therefore, the adsorption time selected in this study is 6 h.Approximately 0.1 g of CA–SC was weighed, added into 50 mL of 1.5 mM Ca2+ and Mg2+ onto CA–SC are given in 2 values, the pseudo-second-order kinetic equation is more consistent with the experimental data, indicating that chemical adsorption plays an important role in the adsorption process [In addition, we also used the pseudo-first-order and pseudo-second-order kinetic models to fit the experimental data. The derived kinetic models’ parameters for Ca process .t = qe (1 − exp(−k1t)), the pseudo-second-order kinetic equation is qt = qe (1 − 1/(1 + qek2t)) [1 and k2 are the rate constant of pseudo-first-order and pseudo-second-order, respectively, qt is the amount of metal adsorbed at a certain time (t), and qe is the amount of metal adsorbed at equilibrium.The pseudo-first-order kinetic equation is q qek2t)) ,26, wher2+ (or Mg2+), stirred at 0 °C, 5 °C, 10 °C, 15 °C, 20 °C, 25 °C, 30 °C, 35°C, or 40 °C for 6 h, and filtered. 2+ and Mg2+ remains at 94–97%, which indicates that CA–SC is suitable for treating water containing Ca2+ and Mg2+ at different temperatures.Approximately 0.1 g of CA–SC was weighed, added into 50 mL of 1.5 mM Ca2+, Zn2+, Co2+, Pb2+, Cr3+, Ca2+, and Mg2+) are shown in 2+, Zn2+, Co2+, Pb2+, Cr3+, Ca2+, and Mg2+ and can remove more than 94% of the corresponding metal ions from the solution. This result may be attributed to the combination of carboxyl, hydroxyl, and amino functional groups on CA–SC with metal ions through coordination. In the presence of other ions , CA–SC can still remove 87.2% of Ca2+ and 86.5% of Mg2+ in the mixed solution. Thus, CA–SC can be used for treating wastewater containing heavy metal ions and can effectively soften hard water in the presence of multiple ions.The adsorption abilities of CA–SC for different metal ions , stirred at room temperature for 6 h, then filtered. The remaining Ca2+ and Mg2+ concentrations in the filtrate were determined by the ICP-OES. 2+ and Mg2+, the adsorption capacity of CA–SC for Ca2+ and Mg2+ gradually increases and remains stable as the concentration further increases. When the initial concentration of Ca2+ and Mg2+ exceeds 8.0 mM, the adsorption capacity of CA–SC for Ca2+ and Mg2+ reaches saturation. Thus, the maximum adsorption capacities of CA–SC for Ca2+ and Mg2+ are 62.38 and 36.23 mg/g, respectively. These values are higher than those of the most reported Ca2+-sorbents and Mg2+-sorbents . Further, we also analyzed the O 1s and N 1s spectra. As illustrated in 2+, the O 1s peak at 532.4 eV (C–O) and the N 1s peak at 399.6 eV of CA–SC shifted to 532.6 eV and 399.8 eV, respectively [3 hybrid orbitals of Mg2+ that reduced the electron cloud density of N, O atoms [2+ ions  ions on the adsorbent. Therefore, we chose 50 mM of nitric acid as the eluent to regenerate the adsorbent in this study. As shown in 2+ and Mg2+ ions were maintained between 93–97%. In addition, after nine cycles of use, the change in the CA–SC morphology was minimal. As such, CA–SC has good stability, and its physical and chemical properties remain stable after multiple cycles of use.In order to regenerate the adsorbent, nitric acid, acetic acid, hydrochloric acid, and EDTA were employed as the eluents to elute Ca2+ and Mg2+ in aqueous solutions. The maximum adsorption capacities for Ca2+ and Mg2+ reach 62.38 and 36.23 mg/g, respectively. In addition, CA–SC adsorbent can be regenerated by simple pickling, and its adsorption performance remains stable after repeated use. Thus, CA–SC has broad application prospects in the treatment of water containing Ca2+ and Mg2+ ions.In summary, a novel CA–SC sorbent was successfully developed using green and safe sodium alginate and sodium citrate as raw materials. Through chemical coordination, the prepared CA–SC can effectively remove CaSodium citrate, sodium alginate , 2-morpholineethanesulfonic acid, N-hydroxysuccinimide (NHS), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (EDC), ethylenediamine, and metal salts were all purchased from J & K Scientific Ltd . Except that sodium alginate is chemically pure, all other reagents used in this study were of analytical grade. The experimental water used in this work was double-distilled water. Lake water was collected from Anqing Linghu Lake, and river water was obtained from the Anqing section of the Yangtze River.The macro and micro morphological images of CA–SC were taken using a Canon digital camera and an electronic scanning electron microscope (SEM), respectively. The chemical composition and functional groups of the adsorbent were determined using an infrared spectrometer and X-ray photoelectron spectrometer (XPS). The concentration of each metal ion in a solution was measured using an inductively coupled plasma emission spectrometer (ICP-OES).First, 1.5 g of sodium alginate was dissolved in 2-morpholineethanesulfonic acid buffer solution (pH 5.5), added with 0.08 g of EDC and 0.06 g of NHS successively, and mechanically stirred for 3 h. Then, 3.0 mL of ethylenediamine was added, and stirring was continued for 6 h. Sodium citrate (1.5 g) was added and stirring commenced for 6 h. The solution was added into the calcium ion solution by using a 5.0 mL syringe. The hydrogels were washed three times with distilled water and immersed in 50 mL of distilled water. They were placed in a vacuum freeze dryer, frozen, and vacuum dried to obtain the final CA–SC.2+ solution. The mixture was magnetically stirred for 6 h at room temperature, and then filtered. The remaining Ca2+ concentration in filtrate was determined using ICP-OES. The adsorption process of other metal ions is the same as above process, except that Ca2+ is replaced by target metal ion.For the adsorption experiment, about 0.1 g of CA–SC was weighed and added to 50 mL of 1.5 mM Ca2+-loaded CA–SC was added to 50 mL of 50 mM nitric acid solution. The mixture was magnetically stirred for 3 h, filtered, and the sorbent was washed with distilled water. The amount of metal ions in the eluent was measured by the ICP-OES. The desorption process of Mg2+ is the same as above, except that Ca2+-loaded CA–SC is replaced by Mg2+-loaded CA–SC.For the desorption experiment, Ca2+-loaded CA–SC into 50 mL of 50 mM nitric acid solution. After magnetic stirring for 3 h, it was filtered, the sorbent was washed with distilled water, calcium hydroxide solution (20 mM), and distilled water in sequence, and dried in an oven at 50 °C for 4 h.Adsorbent regeneration and circulation tests were performed by adding Ca


The hippocampus is a critical organ for irradiation. Thus, we explored changes in hippocampal volume according to the dose delivered and the location relative to the glioblastoma.40% was < 7.4 Gy, in the group 2 (n = 13), only the Hcontra D40% was < 7.4 Gy, and in the group 3 (n = 30), the D40% for both hippocampi was > 7.4 Gy.All patients were treated for glioblastoma with surgery, concomitant radiotherapy and temozolomide, and adjuvant temozolomide. Hippocampi were retrospectively delineated on three MRIs, performed at baseline, at the time of relapse, and on the last MRI available at the end of follow-up. A total of 98, 96, and 82 hippocampi were measured in the 49 patients included in the study, respectively. The patients were stratified into three subgroups according to the dose delivered to 40% of the hippocampus. In the group 1 (n = 6), the hippocampal Dmax (p = 0.001), D98% (p = 0.028) and D40% (p = 0.0002). After adjustment for the time of MRI, these correlations remained significant. According to the D40% and volume at MRIlast, the hippocampi decreased by 4 mm3/Gy overall.Regardless of the time of measurement, homolateral hippocampal volumes were significantly lower than those contralateral to the tumor. Regardless of the side, the volumes at the last MRI were significantly lower than those measured at baseline. There was a significant correlation among the decrease in hippocampal volume regardless of its side, and DThere was a significant relationship between the radiotherapy dose and decrease in hippocampal volume. However, at the lowest doses, the hippocampi seem to exhibit an adaptive increase in their volume, which could indicate a plasticity effect. Consequently, shielding at least one hippocampus by delivering the lowest possible dose is recommended so that cognitive function can be preserved.Trial registration Retrospectively registered.The online version contains supplementary material available at 10.1186/s13014-021-01835-0. Glioblastoma (GBM), the most common brain cancer in adults, is treated by radiotherapy (RT) plus concurrent and adjuvant temozolomide as first-line treatment in fit patients . Some raAccording to trials investigating brain metastasis, dose constraints have been described for both hippocampi , 10. In Trials studying hippocampal shielding and cognitive consequences have mainly been designed for and conducted in patients with whole-brain irradiation or stereotactic irradiation of multiple metastases leading to an equivalent dose in both hippocampi , 9, 10. Physiologically, the decreasing hippocampi volume in one year was between 0.8 and 4.4% of the initial volume . In a meMany authors have investigated the role of hippocampal and memory disorders in numerous pathologies , 25–29. tablThe first purpose of the study was to evaluate changes in hippocampus size among irradiated GBM patients during the follow-up according to the tumor side and the received dose. Secondly, this study tried to assess whether the changes to the nonirradiated/low-irradiated hippocampus are similar to those of the higher-irradiated hippocampus.The institutional review board approved this retrospective study. All patients gave their consent to collect and analyze their data, and all live patients specifically agreed to participate in this study, according to the French CNIL law MR004.Forty-nine patients with GBM, treated with irradiation, were retrospectively analyzed in this study. There were 34 males and 15 females with a median age of 61-years old . Twenty-five tumors were located in the left cerebral hemisphere, and 24 were located in the right cerebral hemisphere.dosimetric), the second at the time of relapse (MRIrelapse), with a median interval of 4.6 months  after the end of RT, and the third was the last MRI during follow-up (MRIlast), with a median interval of 17.6 months  after the end of RT. The median time interval between MRIrelapse and MRIlast was 11.4 months .All MR images were acquired using a Signa Excite HDx 3.T™ system  with an 8-channel dedicated head coil. The MRI scanning protocol included pre- and postcontrast 1-mm, 3-dimensional (3D) volumetric T1-weighted multiecho magnetization-prepared rapid-acquisition gradient echo (MPRAGE) images, and 3D T2-weighted fluid-attenuated inversion recovery (FLAIR) images. Three MRI image sets were analyzed. The first MRI was obtained with a median interval of 13 days  before the start of RT (MRIThe Planning Target Volume (PTV) included tumors visualized on a gadolinium-enhanced T1 weighted MPRAGE sequence plus a 10 mm-margin completed with edema in the FLAIR sequence, finally encompassed by a 3-mm margin. GBM patients were irradiated at a dose of 60 Gy in 30 daily fractions of 2 Gy, five days a week. All the patients received concomitant chemotherapy with temozolomide at a median daily dose of 140 mg . Forty-three patients underwent a median number of 6 cycles (1–10) of adjuvant chemotherapy at a median daily dose of 340 mg  according to the EORTC/NCIC protocol .dosimetric and retrospectively delineated from the same MRI sequence on the MRIrelapse, and the MRIlast, according to atlas [Hippocampi were prospectively delineated on the gadolinium-enhanced T1-weighted MPRAGE sequence with 1-mm slices MRIto atlas , 32. Hipto atlas .contra) and homolateral (Hhomo) to the GBM, and the composite bilateral consisted of the sum of Hcontra and Hhomo (Hsum). At baseline MRIdosimetric, MRIrelapse, and MRIlast, the numbers of delineated hippocampi were 98, 96, and 82, respectively. No patient had both hippocampi censored.Hippocampi were not included if there was any distortion in the hippocampal anatomy due to postsurgical effects or proximity/invasion of the tumor. Hippocampal volumes were stratified into contralateral (H40% < 7.4 Gy for Hsum. If this aim could not be reached (mainly due to the proximity of one hippocampus to the tumor), then this constraint was imposed on the contralateral hippocampus. In the case of cross-median line GBM, the planning tried to reach the lowest dose as possible in the Hcontra. However, hippocampal constraint respect was never preferred to the tumor coverage (D98% > 95% of the prescribed dose) to limit the risk of GBM relapse.The dose constraint was D40% was < 7.4 Gy, in group 2 (n = 13), only Hcontra D40% was < 7.4 Gy, and in group 3 (n = 30), both hippocampal D40% were > 7.4 Gy. Furthermore, hippocampi were split into four subgroups according to the D40%, < 7.4 Gy, between 7.4 Gy and < 30 Gy, between ≥ 30 Gy and < 50 Gy, and ≥ 50 Gy.Finally, the entire patient group was split into three subgroups according to the dose delivered to 40% of the hippocampus. In group 1 (n = 6), the hippocampal Ddosimetric , on MRIrelapse , and MRIlast .Volumes of hippocampi were determined on MRImin), mean dose (max), D2%, D10%, D40%, D50%, D80%, and D98% were collected for each hippocampus and for the combination of both. According to the linear-quadratic model, for the hippocampi receiving less than 2 Gy per fraction, doses were recalculated with an α/β = 2 Gy. The change in hippocampal volumes was analyzed according to the doses, follow-up time, and contact/proximity to the GBM using Pearson's product-moment correlation. Comparisons of the distribution of volumes, doses, and percentages between homolateral and contralateral hippocampus were performed with the T.Test. RStudio Version 1.2.5033 was used to perform statistical calculations.The minimum dose , Hhomo-relapse versus Hcontra-relapse (p < 0.002), and Hhomo-last versus Hcontra-last (p < 0.003) , Hcontra-j0 versus Hcontra-last (p = 0.049). There was no significant difference in the measurements between MRIrelapse and MRIlast, neither for Hhomo nor Hcontra , Hhomo-relapse-G3 versus Hcontra-relapse-G3 (p = 0.01), and Hhomo-last-G3 versus Hcontra-last-G3 (p = 0.01) , Hhomo-relapse-G1 versus Hhomo-relapse-G3 (p = 0.02), Hhomo-last-G1 versus Hhomo-last-G3 (p = 0.01) and Hcontra-last-G1 versus Hcontra-last-G3 (p < 0.01). There was no significant difference in volume between G1 and G2 and between G2 and G3       .On both sides, the volume decrease at MRImin, D2%, Dmax, D98%, 10%, D40%, D50%, D80%, and D100%, the values for Hhomo were significantly higher than those for Hcontra .For Dhomo than for Hcontra .Before and after recalculation with a 2-Gy equivalent-dose, each analyzed dose value was significantly higher for H40% and D40%Eq. 2 Gy were studied among the three groups. For group 1, there was no difference in D40% and D40%Eq. 2 Gy for Hhomo and Hcontra. For group 2, the median D40% and D40%Eq. 2 Gy values were significantly higher in Hhomo than in Hcontra, 38.5 Gy versus 5.1 Gy (p < 0.001) and 31.6 Gy and 2.8 Gy (p < 0.0001), respectively. For group 3, comparable differences were observed for 59.3 Gy versus 18.5 Gy (p < 0.001) and 58.9 Gy versus 12.1 Gy (p < 0.0001), respectively.Dmax (p = 0.001), D98% (p = 0.028) and D40% (p = 0.0002). Adjusted to the time of analysis, these correlations remained significant. According to D40% and volume at MRIlast time, overall hippocampi decreased by 4 mm3/Gy. However, these changes were not linear when the doses were stratified into four subgroups, < 7.4 Gy, between 7.4 Gy and < 30 Gy, between ≥ 30 Gy and < 50 Gy, and ≥ 50 Gy. The slopes were + 94.3 mm3/Gy, − 8.6 mm3/Gy, − 44.5 mm3/Gy, and − 112.2 mm3/Gy, respectively.There was a significant correlation between the decrease in the volume of the hippocampus, regardless of its side and Dhomo and Hcontra from MRIdosimetric to MRIlast, according to D40%, was opposite, with slopes of − 124 mm3/Gy and + 172 mm3/Gy, respectively.For group 1, the change in volume for Hhomo and Hcontra's evolution was also opposite, − 15 mm3/Gy and + 154 mm3/Gy, respectively.For group 2, Hhomo and Hcontra volumes followed the same directions, with − 19.7 mm3/Gy and − 19.7 mm3/Gy, respectively.For group 3, the slopes of the change in volume for H40%, including both hippocampi, and were proposed secondary to the results of the first study, which used whole-brain radiation therapy, where hippocampi were irradiated or shielded symmetrically. In contrast, only two studies have focused on asymmetric irradiation in glioma [The dose constraints of hippocampi are currently well defined to dramatically and efficiently decrease the hippocampal dose and, consequently, memory impairment. However, these dose constraints were primarily referenced by Dn glioma , 34.40% in hippocampal volumes measured by MRI and to analyze the change in the hippocampus contralateral to the GBM after irradiation. This study clearly showed that the volume of hippocampi decreased after radiotherapy in patients irradiated for GBM. However, the decrease in hippocampal size depended on the tumor side and relied on the received radiation dose. These factors could explain the variability in memory disturbances after brain irradiation.To our knowledge, this is the first study to investigate D., for protection, hippocampi were manually delineated according to the protocol but only after the planning dose calculation was determined [Delineation of hippocampi, which requires training and support of the atlas, have been recommended , 32. In termined . Notablytermined –37. Comptermined . The maitermined . In the In the current series, the median decrease in hippocampal volumes varied from 4 to 17.6% depending on the tumor side, received dose, and time after irradiation. In contrast, Prust et al. did not observe any change in the nine-month MRI-follow-up in 14 patients treated for GBM . This diGondi et al. did not show any correlation with the hippocampus analyzed separately . In contdosimetry) cannot be excluded, but other causes should also be considered  [In this work, we showed that the median volume of the homolateral hippocampi relative to the glioblastoma was always lower that of the contralateral hippocampi. The impact of glioblastoma on hippocampi functioning and homeostasis is unknown, but these results suggest an interaction. However, the consequences of surgery always being performed before the reference MRI (MRIintake…) . Anotherintake…) , 28, 41.Animal studies have shown that when the brains of young rats are unilaterally irradiated, the volume of the irradiated hippocampus is reduced compared to that of the nonirradiated side, corresponding to apoptosis, which induces the loss of neural stem cells and progenitor cell proliferation , 43. A p40% in the bilateral hippocampi > 7.4 Gy (p = 0.043) [In the study by Gondi et al., risk impairment was significantly correlated with a D= 0.043) .p = 0.03). The mean hippocampal volume was significantly reduced one year after high-dose (> 40 Gy) radiation therapy, but not after low-dose (< 10 Gy) radiation therapy [max, D98%, and D40% with decreasing hippocampal volume. Furthermore, we showed that the volume decreased continuously with D40% from > 7.5 to > 50 Gy. Notably, for a D40% < 7.4 Gy, hippocampal volumes increased. Dose-dependent brain changes were also demonstrated for white matter [40% was < 7.4 Gy because the GBM was far enough away from the hippocampus and consequently, the hippocampus was not in, or near the radiation fields.Seibert et al. showed that hippocampal volume loss was significantly correlated with the mean RT dose delivered to the hippocampus , but a median reduction of 5.55% in hippocampi that received more than 50 Gy in the same period.Siebert et al. showed a one-year atrophy rate of 6% in the hippocampi that received a dose > 40 Gy . This va40% less than 7.4 Gy did not show any atrophy in the hippocampus; in contrast the volume increased significantly. The lack of hippocampus atrophy at low dose was reported in several previous study [In our current series, contralateral hippocampi that received a Dus study , 36, 39.us study . Memory us study , 24.Notably, regardless of the tumor distance, the homolateral hippocampus volume was always significantly smaller than the contralateral hippocampus volume. This relative atrophy suggested that dose was not the sole cause of this decline. Other causes could be vascular disruption and permeability , alteratThis study was limited by the absence of specific cognitive performance measures to correlate with the observed structural neuroimaging changes. Validated cognitive tests are not always used in routine clinical practice, precluding clinical neurologic observation analysis in retrospective studies. However, these tests should be precise and split the left or right hippocampus , and doscontra could give possibility of hippocampus volume adaptation and function recovery. However, several future improvement have to be directed to demonstrate the clinical hypotheses [This study showed that the low-irradiated hippocampus volume and/or far from the GBM changes differently than the hippocampus near to the tumor and/or receiving high irradiated doses. These observations suggest that tumor could more deteriorate hippocampus structure and function than radiotherapy and that shielding of Hpotheses . The rolpotheses . The volpotheses . Ultimatpotheses . In addipotheses To correlate neurocognitive outcomes with structural brain changes, prospective longitudinal trials are needed to examine performance in multiple cognitive domains in concert with serial neuroimaging .40%-dependent atrophy effect on the irradiated hippocampus. The volume of the contralateral hippocampus increased when irradiated at a D40% < 7.4 Gy increased, suggesting a compensatory reaction. Thus, limiting the radiation dose to the greatest extent possible in at least one hippocampus is recommended, when relevant, in cases of asymmetrical brain cancer.This study demonstrated a DAdditional file 1. Annex 1: Relevant comparison of volumes according to MRI. Annex 1a: Comparison of volumes measured on MRI. Annex 1b: Comparison between changes in volume during the intervals between MRIs. Annex 1c: Comparison between changes in percent volume during the intervals between MRIsAdditional file 2. Annex 2: Relevant comparison of hippocampal volumes their changes according to the time of the MRIs. Annex 2a: Comparison between volumes at a given MRI time according to subgroup: In group 1 (G1: n=6), in both hippocampi, the D40% was < 7.4 Gy; in group 2 (G2: n=13), the Hcontra D40% was < 7.4 Gy; and in group 3 (G3: n=30), the D40% for both hippocampi was > 7.4 Gy. Annex 2b: Comparison between volumes measured on different MRIs and according to subgroup: In group 1 (G1: n=6), in both hippocampi, the D40% was < 7.4 Gy; in group 2 (G2: n=13), the Hcontra D40% was < 7.4 Gy; and in group 3 (G3: n=30), the D40% for both hippocampi was > 7.4 Gy. Annex 2c: Comparison between changes in volumes during the interval between MRIs and according to subgroup: In group 1 (G1: n=6), in both hippocampi, the D40% was < 7.4 Gy; in group 2 (G2: n=13), the Hcontra D40% was < 7.4 Gy; and in group 3 (G3: n=30), the D40% for both hippocampi was > 7.4 Gy. Annex 2d: Comparison between changes in % volumes during interval between MRIs and according to subgroup: In group 1 (G1: n=6), in both hippocampi, the D40% was < 7.4 Gy; in group 2 (G2: n=13), the Hcontra D40% was < 7.4 Gy; and in group 3 (G3: n=30), the D40% for both hippocampi was > 7.4 Gy