An electrochemical biosensor for fructosyl valine for glycosylated hemoglobin detection based on core-shell magnetic bionanoparticles modified gold electrode

A high-performance amperometric fructosyl valine (FV) biosensor was developed, based on immobilization of fructosyl amino-acid oxidase (FAO) on core-shell magnetic bionanoparticles modified gold electrode. Chitosan was used to introduce amino groups onto the surface of core-shell magnetic bionanoparticles (MNPs). With FAO as an enzyme model, a new fructosyl valine biosensor was fabricated. The biosensor showed optimum response, when operated at 50 mV s(-1) in 0.1 M potassium phosphate buffer, pH 7.5 and 35 degrees C. The biosensor exhibited excellent sensitivity [the detection limit is down to 0.1 mM for EV], fast response time (less than 4 s), wide linear range (from 0 to 2 mM). Analytical recovery of added FV was 95.00-98.50%. Within batch and between batch coefficients of variation were <2.58% and <5.63%, respectively. The enzyme electrode was used 250 times over 3 months, when stored at 4 degrees C. (C) 2011 Elsevier B.V. All rights reserved.