title: An acetylcholinesterase biosensor based on graphene-gold nanocomposite and calcined layered double hydroxide.
abstract: In this study, a novel acetylcholinesterase-based biosensor was fabricated. Acetylcholinesterase (AChE) was immobilized onto a glassy carbon electrode (GCE) with the aid of Cu-Mg-Al calcined layered double hydroxide (CLDH). CLDH can provide a bigger effective surface area for AChE loading, which could improve the precision and stability of AChE biosensor. However, the poor electroconductibility of CLDHs could lead to the low sensitivity of AChE biosensor. In order to effectively compensate the disadvantages of CLDHs, graphene-gold nanocomposites were used for improving the electron transfer rate. Thus, the graphene-gold nanocomposite (GN-AuNPs) was firstly modified onto the GCE, and then the prepared CLDH-AChE composite was immobilized onto the modified GCE to construct a sensitive AChE biosensor for pesticides detection. Relevant parameters were studied in detail and optimized, including the pH of the acetylthiocholine chloride (ATCl) solution, the amount of AChE immobilized on the biosensor and the inhibition time governing the analytical performance of the biosensor. The biosensor detected chlorpyrifos at concentrations ranging from 0.05 to 150μg/L. The detection limit for chlorpyrifos was 0.05μg/L.
authors.affiliation: School of Agriculture and Food Engineering, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo 255049, Shandong Province, PR China.
authors.forename: Chen
authors.initials: C
authors.lastname: Zhai
authors.affiliation: School of Agriculture and Food Engineering, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo 255049, Shandong Province, PR China.
authors.forename: Yemin
authors.initials: Y
authors.lastname: Guo
authors.affiliation: School of Agriculture and Food Engineering, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo 255049, Shandong Province, PR China. Electronic address: sunxia2151@sina.com.
authors.forename: Xia
authors.initials: X
authors.lastname: Sun
authors.affiliation: Shandong Water Conservancy Technician Institute, No. 169, Shuiyuan Road, Zibo 255130, Shandong Province, PR China.
authors.forename: Yuhe
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: School of Agriculture and Food Engineering, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo 255049, Shandong Province, PR China.
authors.forename: Xiangyou
authors.initials: X
authors.lastname: Wang
mesh_terms: D000110:Acetylcholinesterase; D000327:Adsorption; D000538:Aluminum Silicates; D000838:Anions; D015374:Biosensing Techniques; D004390:Chlorpyrifos / Q000032:analysis*; D002800:Cholinesterase Inhibitors / Q000032:analysis*; D000077215:Clay; D003102:Colloids; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D023381:Endpoint Determination; D004800:Enzymes, Immobilized; D004867:Equipment Design; D005506:Food Contamination / Q000032:analysis*; D008670:Metals; D053761:Nanocomposites; D010573:Pesticide Residues / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013499:Surface Properties; D014675:Vegetables / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D000838:Anions; D002800:Cholinesterase Inhibitors; D003102:Colloids; D004800:Enzymes, Immobilized; D008670:Metals; D010573:Pesticide Residues; D000110:Acetylcholinesterase; D004390:Chlorpyrifos; D000077215:Clay
keywords: Acetylcholinesterase biosensor; Cu–Mg–Al calcined layered double hydroxide; Graphene–gold nanocomposite; Pesticides