title: Preparation of parathion imprinted polymer beads and its applications in electrochemical sensing.
abstract: Parathion imprinted polymer beads were prepared by free radical polymerization using parathion as template, methacrylic acid as functional monomer, divinyl benzene as cross-linking reagent and 2,2'-azobis(isobutyronitrile) as initiator. The obtained molecularly imprinted beads were characterized with transmission electron micrograph. The rebinding properties of these imprinted beads towards parathion were studied by saturation binding experiments using ultraviolet/visible spectroscopy. Effects of the template, functional monomer, cross-linking reagent and initiator on selective adsorption of parathion were investigated. The high selectivity of the imprinted beads was successfully demonstrated by their selective adsorption of free parathion from an ethanol-water (v/v=1:5) solution. In addition, the parathion imprinted beads were dispersed into dihexadecyl hydrogen phosphate solution at the concentration of 1.0 mg mL(-1). By coating this solution onto a glassy carbon electrode surface, a molecularly imprinted electrochemical sensor for parathion was obtained. The electrochemical sensor exhibited good selectivity and fast response to parathion. Under optimized experimental conditions, the peak currents were found linearly proportional to the parathion concentration in the range of 1.0×10(-7) mol L(-1) to 1.0×10(-5) mol L(-1) with a detection limit of 5.4×10(-8) mol L(-1) (S/N=3). The developed sensor was successfully employed for the determination of parathion in pear juice samples.
authors: Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission, College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, China. lichychem@163.com
authors: Chunya
authors: C
authors: Li
authors: Guoqing
authors: G
authors: Zhan
authors: Ming
authors: M
authors: Ma
authors: Zhengguo
authors: Z
authors: Wang
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D005609:Free Radicals / Q000737:chemistry; D057230:Limit of Detection; D008689:Methacrylates / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D008863:Microspheres; D054802:Molecular Imprinting / Q000379:methods*; D009570:Nitriles / Q000737:chemistry; D010278:Parathion / Q000032:analysis*; D058105:Polymerization; D031989:Pyrus / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry
chemical_list: D003432:Cross-Linking Reagents; D005609:Free Radicals; D008689:Methacrylates; D009570:Nitriles; D014753:Vinyl Compounds; C008384:methacrylic acid; D010278:Parathion; D002244:Carbon; C004526:azobis(isobutyronitrile); C004985:divinyl benzene