Poly(amino acid) Multilayers Modified Dendritic Mesoporous Silica Nanoparticles Achieve Effective Enzyme Stability for Ultrasensitive Immunoassay.
Enzyme-linked immunosorbent assay (ELISA) is one of the most common techniques in biomedical detection; however, the poor sensitivity in early diagnosis for some diseases seriously limits its application. In this work, we developed an ultrasensitive ELISA system that is based on horseradish peroxidase (HRP)-loaded dendritic mesoporous silica nanoparticles (DMSN) modified with poly(amino acid) multilayers (defined as DSHP). A large amount of HRP adsorption was achieved in center-radial mesoporous channels of DMSN because of the high specific surface area and large pore size, leading to significant signal amplification. Additionally, DSHP could not only effectively maintain HRP activity for at least 10 days but also provide preferable protection for HRP activity even at high temperatures or a wide pH range. Moreover, the DSHP system exhibited admirable signal amplification performance with a limit of detection of 0.667 fM and a wide detectable range from 6.67 × 10-4 to 6.67 × 105 pM, whose sensitivity was 104 times higher than that of the conventional ELISA. We believe that the DSHP will offer a new strategy for signal amplification of the ELISA system in clinical diagnosis.
['Wang|Xuewei|X|', 'Wang|Hongyu|H|', 'Tang|Jinlong|J|', 'Wang|Shihui|S|', 'Shi|Dongjian|D|', 'Shen|Heyun|H|http://orcid.org/0000-0001-7960-3864']
D000596:Amino Acids D002942:Circular Dichroism D004795:Enzyme Stability D004797:Enzyme-Linked Immunosorbent Assay D006735:Horseradish Peroxidase D006863:Hydrogen-Ion Concentration D057230:Limit of Detection D053758:Nanoparticles D000071228:Polyelectrolytes D016062:Porosity D012822:Silicon Dioxide D013499:Surface Properties D013696:Temperature D013816:Thermodynamics
poly(amino acid) dendritic mesoporous silica nanoparticle ELISA horseradish peroxidase signal amplification layer by layer