A biorecognition system for concanavalin a using a glassy carbon electrode modified with silver nanoparticles, dextran and glucose oxidase

• Published in: Mikrochimica acta (1966) Vol. 182; no. 3-4; pp. 797 - 803
• Main Authors: Liu, Xiaofang, Ou, Xin, Lu, Qiyi, Chen, Shihong, Wei, Shaping
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01-02-2015; Springer
• Subjects: Affinity; Analysis; Analytical Chemistry; Biosensors; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Concanavalin A; Detectors; Dextran; Dextrose; Electric potential; Electrodes; Glassy carbon; Glucose; Graphene; Infrared spectroscopy; Lectins; Microengineering; Nanochemistry; Nanoparticles; Nanotechnology; Original Paper; Oxidases; Silver; Bio-recognition system; Reduced graphene oxide; Concanavalin A; Biosensor; Silver nanoparticles
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-014-1390-7

Concanavalin A (Con A) was chosen as a model lectin protein for an electrochemical study on the interaction between lectins and carbohydrates. A composite prepared from reduced graphene oxide and silver nanoparticles (rGO-AgNPs) acted as a redox probe, and phenoxy-derivatized dextran (DexP) and glucose oxidase (GOx) acted as recognition elements. The rGO-AgNPs, DexP and GOx were deposited on the surface of a glassy carbon electrode. The immobilized DexP and GOx showed high affinity for the target lectin Con A. The surface-modified biosensor was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, UV–vis absorption spectra, cyclic voltammetry and electrochemical impedance spectroscopy. Due to the high affinity of Con A for both DexP and GOx, the biosensor displays a detection limit for Con A that is as low as 0.67 ng mL
−1
at a working voltage of 48 mV. The response is linear in the 2.0–322 ng mL
-1
concentration range, thus offering a sensitive means for the determination of Con A.
Graphical Abstract
This work presented a simple bio-recognition system with rGO-AgNPs as redox probes, DexP and GOx as bio-recognition elements for sensitive detection of Con A. The detection limit for Con A that is as low as 0.67 ng mL
−1
at a working voltage of 48 mV.