A label-free photoelectrochemical aptasensor based on nitrogen-doped graphene quantum dots for chloramphenicol determination.
A photoelectrochemical (PEC) sensing platform for chloramphenicol (CAP) detection was constructed using nitrogen-doped graphene quantum dots (N-GQDs) as transducer species and label-free aptamer as biological recognition element. N-GQDs, synthesized via a facile one-step hydrothermal method, were explored to achieve highly efficient photon-to-electricity conversion under visible light irradiation. The obtained N-GQDs were characterized by transmission electron microscopy (TEM), which displayed a narrow size distribution with a mean diameter of 2.14 nm. The X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared spectroscopic (FT-IR) analysis confirmed that nitrogen was successfully doped in GQDs. The UV-visible absorption spectra indicated that nitrogen doping obviously enhanced the absorption of GQDs in visible light region. As a result, the PEC activity of GQDs was promoted by nitrogen doping. Additionally, the π-conjugated structure of N-GQDs provided an excellent platform for aptamer immobilization via π-π stacking interaction. Such an aptamer/N-GQDs based sensor showed a linear PEC response to CAP concentration in the range of 10-250 nM with a detection limit (3 S/N) of 3.1 nM. The developed PEC aptasensor exhibited high sensitivity and selectivity, good reproducibility and high stability.
['Liu|Yong|Y|', 'Yan|Kai|K|', 'Okoth|Otieno Kevin|OK|', 'Zhang|Jingdong|J|']
D000900:Anti-Bacterial Agents D052157:Aptamers, Nucleotide D002701:Chloramphenicol D003217:Conductometry D004784:Environmental Monitoring D004867:Equipment Design D019544:Equipment Failure Analysis D006108:Graphite D009584:Nitrogen D010783:Photometry D045663:Quantum Dots D014874:Water Pollutants, Chemical
Nitrogen-doped graphene quantum dots Chloramphenicol Aptamer Photoelectrochemical sensor