title: Label-free immunosensor based on one-step electrodeposition of chitosan-gold nanoparticles biocompatible film on Au microelectrode for determination of aflatoxin B1 in maize.
abstract: Gold nanoparticles (AuNPs) embedded in chitosan (CHI) film, well-dispersed and smaller in size (about 10 nm), were fabricated by one-step electrodeposion on Au microelectrode in solution containing chitosan and chloride trihydrate. The nano-structure CHI-AuNPs composite film offers abundant amine groups, good conductivity, excellent biocompatibility and stability for antibody immobilization. The combination of aflatoxin B1 (AFB1) with immobilized antibody introduces a barrier to electron transfer, resulting in current decreasement. The morphologies and characterizations of modified microelectrodes were investigated by scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR). The proposed non-enzyme and label-free immunosensor exhibited high sensitive amperometric response to AFB1 concentration in two linear ranges of 0.1 to 1 ng mL(-1) and 1 to 30 ng mL(-1), with the detection limit of 0.06 ng mL(-1) (S/N=3). The immunoassay was also applied for analysis of maize samples spiked with AFB1. Considering the sample extraction procedure, the linear range and limit of detection were assessed to be 1.6-16 ng mL(-1) and 0.19 ng mL(-1) respectively. The simple method showed good fabrication controllability and reproducibility for immunosensor design.
authors: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, PR China; Graduate University of Chinese Academic of Sciences, Beijing 100190, PR China; College of Information Science and Engineering, Henan University of Technology, Zhengzhou 450001, PR China; Key Laboratory of Grain Information Processing and Control of Ministry of Education, Henan University of Technology, Zhengzhou 450001, PR China.
authors: Haihua
authors: H
authors: Ma
authors: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Jizhou
authors: J
authors: Sun
authors: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, PR China; Key Laboratory of Grain Information Processing and Control of Ministry of Education, Henan University of Technology, Zhengzhou 450001, PR China. Electronic address: zhangyuan@haut.edu.cn.
authors: Yuan
authors: Y
authors: Zhang
authors: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, PR China.
authors: Chao
authors: C
authors: Bian
authors: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, PR China. Electronic address: shxia@mail.ie.ac.cn.
authors: Shanhong
authors: S
authors: Xia
authors: College of Information Science and Engineering, Henan University of Technology, Zhengzhou 450001, PR China.
authors: Tong
authors: T
authors: Zhen
mesh_terms: D016604:Aflatoxin B1 / Q000737:chemistry / Q000302:isolation & purification*; D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D001672:Biocompatible Materials / Q000737:chemistry; D015374:Biosensing Techniques; D048271:Chitosan / Q000737:chemistry; D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry; D007118:Immunoassay; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D008839:Microelectrodes; D037742:Nanotubes, Carbon / Q000737:chemistry; D003313:Zea mays / Q000737:chemistry
chemical_list: D055910:Antibodies, Immobilized; D001672:Biocompatible Materials; D037742:Nanotubes, Carbon; D006046:Gold; D048271:Chitosan; D016604:Aflatoxin B1
keywords: Aflatoxin B(1); Chitosan; Electrodeposition; Gold nanoparticle; Immunosensor; Microelectrode