title: Mesoporous silica hollow sphere (MSHS) for the bioelectrochemistry of horseradish peroxidase.
abstract: In this work, novel mesoporous silica hollow spheres (MSHS) were chosen as an immobilization matrix, to construct a mediator-free third-generation HRP biosensor. UV-vis spectroscopy revealed that horseradish peroxidase (HRP) entrapped in MSHS could retain its native structure. FTIR spectroscopy and nitrogen adsorption-desorption isotherms indicated that HRP are intercalated into the mesopores. The direct electron transfer of HRP entrapped in MSHS was observed. A pair of stable and well-defined redox peaks of HRP with a formal potential of about -0.150 V (vs. Ag/AgCl) in 0.1M pH 7.0 phosphate-buffered solution (PBS) were obtained. The biosensor exhibited a fast amperometric response to H(2)O(2) with a linear range of 3.9 x 10(-6) to 1.4 x 10(-4)M (R=0.997, N=20). The detection limit was 1.2 x 10(-6)M based S/N=3.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Materials & Thermochemistry Laboratory, Dalian 116023, Liaoning Province, China.
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Cao
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Julan
authors.initials: J
authors.lastname: Zeng
authors.forename: Lixian
authors.initials: L
authors.lastname: Sun
authors.forename: Fen
authors.initials: F
authors.lastname: Xu
authors.forename: Zhong
authors.initials: Z
authors.lastname: Cao
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.forename: Daowu
authors.initials: D
authors.lastname: Yang
mesh_terms: D000327:Adsorption; D001669:Biochemical Phenomena; D015374:Biosensing Techniques; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D004563:Electrochemistry; D004566:Electrodes; D006735:Horseradish Peroxidase / Q000032:analysis* / Q000737:chemistry* / Q000378:metabolism; D009584:Nitrogen; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002244:Carbon; D012822:Silicon Dioxide; D006735:Horseradish Peroxidase; D009584:Nitrogen