Peptide cleavage-based electrochemical biosensor coupling graphene oxide and silver nanoparticles

• Published in: Analytica chimica acta 2019-01, Vol.1047, p.45-51
• Main Authors: Meng, Fanyu, Sun, Haixuan, Huang, Yue, Tang, Yuguo, Chen, Qiang, Miao, Peng
• Format: Article
• Language: English
• Subjects: Biosensor; Biosensors; Chemical reduction; Cleavage; Coupling (molecular); Electrochemistry; Electrodes; Gold; Graphene; Graphene oxide; Immobilization; Linear sweep voltammetry; Nanocomposites; Nanoparticles; Peptide; Peptides; Prostate; Prostate specific antigen; Selectivity; Sensitivity analysis; Silver; Silver chloride; Silver nanoparticles; Target recognition
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2018.09.053

Herein, a novel electrochemical biosensor for sensitive analysis of prostate specific antigen (PSA) is demonstrated. A specific peptide is employed on the gold electrode as a molecular recognition element for target induced cleavage. In the absence of PSA, graphene oxide (GO) is directly immobilized on the peptide modified electrode, which triggers the aggregation of silver ions and subsequent reduction reaction to form silver nanoparticles (AgNPs). Well defined sharp silver stripping peak can thus be achieved, which stands for a highly characteristic solid-state Ag/AgCl reaction. However, in the presence of PSA, the peptide is specifically recognized and cleaved. The resulted product on the electrode surface cannot aid the immobilization of GO and subsequent formation of AgNPs. Therefore, electrochemical response is decreased remarkably, which can be used to indicate the concentration of PSA. This work demonstrates that the combination of the transduction of peptide cleavage event with GO/AgNPs nanocomposites is a promising attempt for PSA analysis with high sensitivity and selectivity. [Display omitted] •A peptide cleavage-based strategy is developed for detection of prostate specific antigen.•Graphene oxide and silver nanoparticles are constructed for signal generation.•Significant silver stripping peak is used to evaluate prostate specific antigen concentration.