title: Electrophoretically deposited polyaniline nanotubes based film for cholesterol detection.
abstract: Polyaniline nanotube (PANI-NT) based films have been fabricated onto indium-tin-oxide (ITO) coated glass plates via electrophoretic technique. These PANI-NT/ITO electrodes have been utilized for covalent immobilization of cholesterol oxidase (ChOx) using glutaraldehyde (Glu) as cross-linker. Structural, morphological and electrochemical characterization of PANI-NT/ITO electrode and ChOx/Glu/PANI-NT/ITO bioelectrode have been done using FT-IR spectroscopy, SEM, electrochemical impedance spectroscopy and cyclic voltammetry techniques. Response studies of the ChOx/Glu/PANI-NT/ITO bioelectrode have been carried out using both linear sweep voltammetry and UV-Visible spectrophotometry. The results of the biosensing studies reveal that this bioelectrode can be used to detect cholesterol in wide detection range of 25-500 mg/dL with high sensitivity of 3.36 mA mg(-1) dL and fast response time of 30 s at pH 7.4. This bioelectrode exhibits very low value of Michaelis-Menten constant of 1.18 mM indicating enhanced interactions between cholesterol and ChOx immobilized onto this nanostructured PANI matrix.
authors.affiliation: Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, Materials Physics and Engineering Division, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, India.
authors.forename: Chetna
authors.initials: C
authors.lastname: Dhand
authors.forename: Pratima R
authors.initials: PR
authors.lastname: Solanki
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Pandey
authors.forename: Monika
authors.initials: M
authors.lastname: Datta
authors.forename: Bansi D
authors.initials: BD
authors.lastname: Malhotra
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002784:Cholesterol / Q000032:analysis*; D002789:Cholesterol Oxidase / Q000737:chemistry / Q000378:metabolism; D004586:Electrophoresis / Q000379:methods*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D012680:Sensitivity and Specificity; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D017971:Tin Compounds
chemical_list: D000814:Aniline Compounds; D004800:Enzymes, Immobilized; D017971:Tin Compounds; C416807:polyaniline; C109984:indium tin oxide; D002784:Cholesterol; D002789:Cholesterol Oxidase