title: Disposable biosensor based on enzyme immobilized on Au-chitosan-modified indium tin oxide electrode with flow injection amperometric analysis.
abstract: Indium tin oxide (ITO) electrode is used to fabricate a novel disposable biosensor combined with flow injection analysis for the rapid determination of H2O2. The biosensor is prepared by entrapping horseradish peroxidase (HRP) enzyme in colloidal gold nanoparticle-modified chitosan membrane (Au-chitosan) to modify the ITO electrode. The biosensor is characterized by scanning electron microscope, atomic force microscope, and electrochemical methods. Parameters affecting the performance of the biosensor, including concentrations of o-phenylenediamine (OPD) and pH of substrate solution, were optimized. Under the optimal experimental conditions, H2O2 could be determined in the linear calibration range from 0.01 to 0.5 mM with a correlation coefficient of 0.997 (n=8). The amperometric response of the biosensor did not show an obvious decrease after the substrates were injected continuously 34 times into the flow cell. The prepared biosensor not only is economic and disposable, due to the low-cost ITO film electrode obtained from industrial mass production, but also is capable with good detection precision, acceptable accuracy, and storage stability for the fabrication in batch.
authors.affiliation: College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China.
authors.forename: Jiehua
authors.initials: J
authors.lastname: Lin
authors.forename: Wei
authors.initials: W
authors.lastname: Qu
authors.forename: Shusheng
authors.initials: S
authors.lastname: Zhang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D048271:Chitosan / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry; D017022:Flow Injection Analysis / Q000379:methods*; D017979:Gold Colloid / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000032:analysis / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D015203:Reproducibility of Results; D017971:Tin Compounds / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D017979:Gold Colloid; D017971:Tin Compounds; C109984:indium tin oxide; D048271:Chitosan; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase