Sensitive and Selective Electrochemical Biosensor Based on ELP-OPH/BSA/TiO2NFs/AuNPs for Determination of Organophosphate Pesticides with p-Nitrophenyl Substituent. Issue 2 (9th December 2016)

• Record Type: Journal Article
• Authors: Bao, Jing; Hou, Changjun; Huo, Danqun; Dong, Qiuchen; Ma, Xiaoyu; Sun, Xiangcheng; Yang, Mei; Galil, Khaled Hussein Abd El; Chen, Wilfred; Lei, Yu
• Is Part Of: Journal of the Electrochemical Society. Volume 164:Issue 2(2017)
• Page Start: G17
• Page End: G22
• Publication Date: 2016-12-09
• Subjects: gold nanoparticles -- pesticides -- organophosphate hydrolase -- titanium oxide nanofibers; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0311702jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : We report herein a new electrochemical bisosensor based on elastin-like polypeptide-organophosphate hydrolase/bovine serum albumin/titanium oxide nanofibers/gold nanoparticles (ELP-OPH/BSA/TiO2 NFs/AuNPs) for highly sensitive and selective, rapid, one-step determination of organophosphate pesticides (OPs) with p -nitrophenyl substituent. ELP-OPH was purified from genetically engineered Escherichia coli ( E. coli ) taking the advantage of thermal-triggered phase-transition of ELP. The surface morphology and crystal structure of the as-prepared ELP-OPH/BSA/TiO2 NFs/AuNPs nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray Diffraction (XRD), respectively. The electrochemical properties and catalytic behavior of the as-prepared electrodes for the determination of methyl parathion were systematically investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometry (i–t). During OPs detection, OP compounds were selectively adsorbed to the TiO2 NFs surface due to the strong affinity of its phosphoric group with TiO2 NFs, while AuNPs were employed to provide a stable interface for promoting electron transfer between biomolecules and electrodes, thus enhanced sensing performance was accomplished. Under the optimized operating conditions, the as-prepared biosensor can detect methyl parathion with a wide dynamic ranges (up to 116.4 μM), a good sensitivity of 734 μA cm −2 mM −1 and the limit of detection (S/N = 3) as low as 29 nM. Its further application for determination of methyl parathion spiked into lake water samples was also demonstrated with an acceptable stability. All these features indicate that the as-developed ELP-OPH/BSA/TiO2 NFs/AuNPs/GCE holds great promise in rapid, sensitive, specific, and reliable detection of organophosphates pesticides.