A non-enzymatic electrochemical immunosensor for microcystin-LR rapid detection based on Ag@MSN nanoparticles

Abstract

A nonenzymatic electrochemical immunosensor based on the [email protected] mesoporous (denoted as [email protected]) nanoparticles was developed for the detection of microcystin-leucine-arginine (MC-LR). Classical electrochemical immunosensor usually employs protein enzymes as biocatalysts to afford amplified signals. However, enzymes are vulnerable to proteolytic degradation, suffering from poor stability. [email protected] nanoparticle which possessed an intrinsic enzyme catalytic activity similar to that of horseradish peroxidase was used to replace protein enzyme to improve the stability and sensitivity. Under the optimized experimental conditions, the nonenzymatic immunosensor exhibits excellent performance (e.g., a detection limit of 0. 2 ng/mL, a linear dynamic range of 3 orders of magnitude, high specificity). With these merits, this stable, simple, sensitive and low-cost nonenzymatic electrochemical immunoassay shows promise for applications in food and environmental monitoring.