title: Electrochemiluminescence biosensor for determination of organophosphorous pesticides based on bimetallic Pt-Au/multi-walled carbon nanotubes modified electrode.
abstract: A novel and highly sensitive electrochemiluminescence (ECL) biosensing system was designed and developed for individual detection of different organophosphorous pesticides (OPs) in food samples. Bimetallic Pt-Au nanoparticles were electrodeposited on multi-walled carbon nanotubes (MWNTs)-modified glass carbon electrode (GCE) to increase the surface area of electrode and ECL signals of luminol. Biocomposites of enzymes from acetylcholinesterase and choline oxidase (AChE and ChOx) were immobilized onto the electrode surface to produce massive hydrogen peroxides (H2O2), thus amplifying ECL signals. Based on the dual-amplification effects of nanoparticles and H2O2 produced by enzymatic reactions, the proposed biosensor exhibits highly sensitivity. The proposed biosensing approach was then used for detecting OPs by inhibition of OPs on AChE. Under optimized experimental conditions, the ECL intensity decreased accordingly with the increase in concentration of OPs, and the inhibition rates of OPs were proportional to their concentrations in the range of 0.1-50nmolL(-1) for malathion, methyl parathion and chlorpyrifos, with detection limit of 0.16nmolL(-1), 0.09nmolL(-1) and 0.08nmolL(-1), respectively. The linearity range of the biosensor for pesticide dufulin varied from 50 to 500nmolL(-1), with the detection limit of 29.7nmolL(-1). The resulting biosensor was further validated by assessment of OPs residues in cabbage, which showed a fine applicability for the detection of OPs in the realistic sample.
authors.affiliation: Jiangsu Key Laboratory of Pesticide Science, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China; State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Shan Shan
authors.initials: SS
authors.lastname: Miao
authors.affiliation: Jiangsu Key Laboratory of Pesticide Science, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Mei Sheng
authors.initials: MS
authors.lastname: Wu
authors.affiliation: Jiangsu Key Laboratory of Pesticide Science, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Li Ya
authors.initials: LY
authors.lastname: Ma
authors.affiliation: Jiangsu Key Laboratory of Pesticide Science, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Xiao Jing
authors.initials: XJ
authors.lastname: He
authors.affiliation: Jiangsu Key Laboratory of Pesticide Science, College of Sciences, Nanjing Agricultural University, Nanjing 210095, China; State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: hongyang@njau.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry; D000429:Alcohol Oxidoreductases / Q000737:chemistry; D052160:Benzothiazoles / Q000032:analysis / Q000737:chemistry; D015374:Biosensing Techniques; D001937:Brassica / Q000737:chemistry; D004390:Chlorpyrifos / Q000032:analysis / Q000737:chemistry; D002800:Cholinesterase Inhibitors / Q000032:analysis / Q000737:chemistry; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D008294:Malathion / Q000032:analysis / Q000737:chemistry; D008743:Methyl Parathion / Q000032:analysis / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D010984:Platinum / Q000737:chemistry
chemical_list: D052160:Benzothiazoles; D002800:Cholinesterase Inhibitors; D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D010575:Pesticides; C576734:dufulin; D008743:Methyl Parathion; D010984:Platinum; D006046:Gold; D006861:Hydrogen Peroxide; D000429:Alcohol Oxidoreductases; C019888:choline oxidase; D000110:Acetylcholinesterase; D004390:Chlorpyrifos; D008294:Malathion
keywords: Acetylcholineesterase; Choline oxidase; Electrochemiluminescence; Luminol; MWCNTs; Organophosphorous pesticides; Pt-Au NPs