A novel acetylcholinesterase biosensor based on carboxylic graphene coated with silver nanoparticles for pesticide detection

作者：Liu, Yongjun; Wang, Guangcan^*; Li, Canpeng; Zhou, Qing; Wang, Min; Yang, Long

来源：Materials Science & Engineering C-Materials for Biological Applications, 2014, 35: 253-258.

DOI：10.1016/j.msec.2013.10.036

• Silver nanoparticles
• Carboxylic graphene
• Nafion
• Acetylcholinesterase biosensor

A novel acetylcholinesterase (AChE) biosensor based on Ag NPs, carboxylic graphene (CGR) and Nafion (NF) hybrid modified glass carbon electrode (GCE) has been successfully developed. Ag NPs-CGR-NF possessed predominant conductivity, catalysis and biocompatibility and provided a hydrophilic surface for AChE adhesion. Chitosan (CS) was used to immobilize AChE on the surface of Ag NPs-CGR-NF/GCE to keep the AChE activities. The AChE biosensor showed favorable affinity to acetylthiocholine chloride (ATCl) and could catalyze the hydrolysis of ATCl with an apparent Michaelis-Menten constant value of 133 mu M, which was then oxidized to produce a detectable and fast response. Under optimum conditions, the biosensor detected chlorpyrifos and carbaryl at concentrations ranging from 1.0 x 10(-13) to 1 x 10(-8) M and from 1.0 x 10(-12) to 1 x 10(-8) M. The detection limits for chlorpyrifos and carbaryl were 5.3 x 10(-14) M and 5.45 x 10(-13) M, respectively. The developed biosensor exhibited good sensitivity, stability, reproducibility and low cost, thus providing a promising tool for analysis of enzyme inhibitors. This study could provide a simple and effective immobilization platform for meeting the demand of the effective immobilization enzyme on the electrode surface.

• 出版日期2014-2-1
• 单位云南大学