title: Iron oxide nanoparticles-chitosan composite based glucose biosensor.
abstract: Iron oxide (Fe(3)O(4)) nanoparticles prepared using co-precipitation method have been dispersed in chitosan (CH) solution to fabricate nanocomposite film on indium-tin oxide (ITO) glass plate. Glucose oxidase (GOx) has been immobilized onto this CH-Fe(3)O(4) nanocomposite film via physical adsorption. The size of the Fe(3)O(4) nanoparticles estimated using X-ray diffraction (XRD) pattern and transmission electron microscopy (TEM) has been found to be approximately 22 nm. The CH-Fe(3)O(4) nanocomposite film and GOx/CH-Fe(3)O(4)/ITO bioelectrode have been characterized using UV-visible and Fourier transform infrared (FTIR) spectroscopic and scanning electron microscopy (SEM) techniques, respectively. This GOx/CH-Fe(3)O(4)/ITO nanocomposite bioelectrode has response time of 5s, linearity as 10-400 mgdL(-1) of glucose, sensitivity as 9.3 microA/(mgdLcm(2)) and shelf life of about 8 weeks under refrigerated conditions. The value of Michaelis-Menten (K(m)) constant obtained as 0.141 mM indicates high affinity of immobilized GOx towards the substrate (glucose).
authors.affiliation: Biomolecular Electronics & Conducting Polymer Research Group, National Physical Laboratory, K.S. Krishnan Marg, New Delhi 110012, India.
authors.forename: Ajeet
authors.initials: A
authors.lastname: Kaushik
authors.forename: Raju
authors.initials: R
authors.lastname: Khan
authors.forename: Pratima R
authors.initials: PR
authors.lastname: Solanki
authors.forename: Pratibha
authors.initials: P
authors.lastname: Pandey
authors.forename: Javed
authors.initials: J
authors.lastname: Alam
authors.forename: Sharif
authors.initials: S
authors.lastname: Ahmad
authors.forename: B D
authors.initials: BD
authors.lastname: Malhotra
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D048271:Chitosan / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation*; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005290:Ferric Compounds / Q000737:chemistry*; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry*; D008839:Microelectrodes; D053758:Nanoparticles / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004800:Enzymes, Immobilized; D005290:Ferric Compounds; C000499:ferric oxide; D048271:Chitosan; D005949:Glucose Oxidase; D005947:Glucose