title: A hydroquinone biosensor using modified core-shell magnetic nanoparticles supported on carbon paste electrode.
abstract: A hydroquinone biosensor was developed and used to determine hydroquinone concentration in compost extracts based on the immobilization of laccase on the surface of modified magnetic core-shell (Fe(3)O(4)-SiO2) nanoparticles. Laccase was covalently immobilized on the magnetic nanoparticles by glutaraldehyde, which was modified with amino groups on its surface. The obtained magnetic bio-nanoparticles were attached to the surface of carbon paste electrode with the aid of a permanent magnet to determine hydroquinone. A good microenvironment for retaining the bioactivity of laccase was provided by the immobilization matrix. The linear range for hydroquinone determination was 1 x 10(-7) to 1.375 x 10(-4)M, with a detection limit of 1.5 x 10(-8)M. The current reached 95% of the steady-state current within about 60s. Hydroquinone concentration in compost extracts was determined by laccase biosensor and HPLC, the results of the two methods were approximately the same.
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China. ezhangyi123@yahoo.com.cn
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Zeng
authors.forename: Lin
authors.initials: L
authors.lastname: Tang
authors.forename: Dan-Lian
authors.initials: DL
authors.lastname: Huang
authors.forename: Xiao-Yun
authors.initials: XY
authors.lastname: Jiang
authors.forename: Yao-Ning
authors.initials: YN
authors.lastname: Chen
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002244:Carbon; D004566:Electrodes; D006873:Hydroquinones / Q000032:analysis*; D008280:Magnetics; D053768:Metal Nanoparticles
chemical_list: D006873:Hydroquinones; D002244:Carbon; C031927:hydroquinone