title: Hydrogen peroxide sensor based on horseradish peroxidase immobilized nanostructured cerium oxide film.
abstract: Nanostructured cerium oxide (NanoCeO(2)) film deposited onto indium-tin-oxide (ITO) glass substrate by solution casting has been used for immobilization of horseradish peroxidase (HRP) via physiosorption technique. X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis and electrochemical techniques have been utilized for characterization of NanoCeO(2)/ITO electrode and HRP/NanoCeO(2)/ITO bioelectrode. The HRP/NanoCeO(2)/ITO electrode exhibits value of the apparent Michaelis-Menten constant (K(m)) as 2.21 microM, linear regression coefficient as 0.998 and linearity for hydrogen peroxide as 1.0-170 microM obtained using electrochemical response measurements. Besides this, HRP/NanoCeO(2)/ITO bioelectrode can be used about 20 times and is stable for 5 weeks at 4 degrees C. The results of photo-response studies carried out on HRP/NanoCeO(2)/ITO bioelectrode indicate reasonable agreement with those obtained using amperometric technique.
authors.affiliation: Department of Science & Technology, Centre on Biomolecular Electronics, National Physical Laboratory, Dr. K S Krishnan Marg, New Delhi 110012, India. aneesaansari@gmail.com
authors.forename: Anees A
authors.initials: AA
authors.lastname: Ansari
authors.forename: Pratima R
authors.initials: PR
authors.lastname: Solanki
authors.forename: B D
authors.initials: BD
authors.lastname: Malhotra
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002563:Cerium / Q000737:chemistry*; D017097:Electric Impedance; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D006735:Horseradish Peroxidase / Q000737:chemistry* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism*; D016014:Linear Models; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D014961:X-Ray Diffraction
chemical_list: D004800:Enzymes, Immobilized; D002563:Cerium; C030583:ceric oxide; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase