Silver deposition directed by self-assembled gold nanorods for amplified electrochemical immunoassay.
A novel electrochemical immunoassay was developed based on the signal amplification strategy of silver deposition directed by gold nanorods (AuNRs), which was in-situ assembled on the sandwich immunocomplex. The superstructure formed by the self-assembly of AuNRs provided abundant active sites for the nucleation of silver nanoparticles. In this pathway, the stripping current of silver was greatly enhanced. Using human immunoglobulin G (HIgG) as a model analyte, the ultrasensitive immunoassay showed a wide linear range of six orders of magnitude from 0.1 fg mL(-1) to 100 pg mL(-1), with the low detection limit down to 0.08 fg mL(-1). The practicality of this electrochemical immunoassay for detection of HIgG in serum was validated with the average recovery of 93.9%. In addition, this enzyme-free immunoassay also has the advantages of acceptable reproducibility and specificity, and thus this immunosensing protocol can be extended to the detection of other low-abundant protein biomarkers.
['Zhang|Hongfang|H|', 'Ning|Danlei|D|', 'Ma|Lina|L|', 'Zheng|Jianbin|J|']
D000818:Animals D055664:Electrochemical Techniques D006046:Gold D007118:Immunoassay D051379:Mice D043942:Nanotubes D012834:Silver D013056:Spectrophotometry, Ultraviolet
Silver deposition Gold nanorod Signal amplification Human IgG Immunosensor