title: Immobilization of urease on poly(N-vinyl carbazole)/stearic acid Langmuir-Blodgett films for application to urea biosensor.
abstract: Urease was immobilized in mixed monolayers of poly(N-vinyl carbazole) (PNVK) and stearic acid (SA) formed at an air-water interface. The monolayers were transferred onto indium-tin-oxide (ITO) coated glass plates using Langmuir-Blodgett (LB) film deposition technique. Urease immobilized on PNVK/SA LB films, characterized using FTIR and UV-visible spectroscopy, was found to exhibit increased stability over a wide pH (6.5-8.5) and temperature (25-50 degrees C) range. Potentiometric measurements on these urease electrodes were carried out using an ammonium ion analyzer. Two values for K(m)(app) were obtained at lower and higher concentrations of substrate urea.
authors.affiliation: Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Krishnan Road, 110012, New Delhi, India.
authors.forename: Rahul
authors.initials: R
authors.lastname: Singhal
authors.forename: Anamika
authors.initials: A
authors.lastname: Gambhir
authors.forename: M K
authors.initials: MK
authors.lastname: Pandey
authors.forename: S
authors.initials: S
authors.lastname: Annapoorni
authors.forename: B D
authors.initials: BD
authors.lastname: Malhotra
mesh_terms: D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D004795:Enzyme Stability; D004800:Enzymes, Immobilized; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011145:Polyvinyls; D012680:Sensitivity and Specificity; D017550:Spectroscopy, Fourier Transform Infrared; D013229:Stearic Acids; D013696:Temperature; D014508:Urea / Q000032:analysis*; D014510:Urease / Q000378:metabolism
chemical_list: D004800:Enzymes, Immobilized; D011145:Polyvinyls; D013229:Stearic Acids; C035125:poly-N-vinylcarbazole; C031183:stearic acid; D014508:Urea; D014510:Urease