The Preparation of C-Reactive Protein Immunosensor Based on Amino Graphene and Hollow Silver Platinum Nanomaterials

A novel and sensitive nonenzymatic sandwich-type electrochemical immunosensor was developed for the detection of C-reactive protein. The catalytic activity of Ag/Pt nanomaterials that possessed an intrinsic enzyme catalytic activity similar to that of horseradish peroxidase (HRP) was utilized as a label to improve the stability and sensitivity using amino graphene as an immobilization matrix. Comparing with the common methods of using HRP as labels for electrochemical detection, Ag/Pt nanoparticles might have longer lifetime than that of enzymes. As far as know, there is no other report using Ag/Pt as catalytic labels for electrocatalyzed reduction of H2O2 to fabricate the amperometric immunosensor. Under the optimized experimental conditions, the detection range of the sensor is from 0.5 ng/mL to 140 ng/mL with a linear correlation coefficient of 0.9934 and the detection limit of 0.17 ng/mL at 3σ . The sensor has good stability, reproducibility and high sensitivity. Therefore, the immunosensor is promising for applications in point-of-care diagnostics.