title: Application of octadecanethiol self-assembled monolayer to cholesterol biosensor based on surface plasmon resonance technique.
abstract: Octadecanethiol (ODT) self-assembled monolayer (SAM) prepared onto gold-coated glass plate has been modified by using nitrene reaction of 1-fluoro-2-nitro-4-azidobenzene (FNAB) that further covalently binds to cholesterol oxidase (ChOx) via thermal reaction. FNAB acts as a bridge (cross-linker) between SAM and ChOx. The ChOx/FNAB/ODT/Au electrode thus fabricated has been characterized using contact angle (CA) measurements, UV-vis spectroscopy, electrochemical techniques and X-ray photoelectron spectroscopy (XPS) technique, respectively. This ChOx/FNAB/ODT/Au bioelectrode has been utilized for estimation of cholesterol in solution using surface plasmon resonance (SPR) technique. This SPR based cholesterol biosensor has linearity from 50 to 500mg/dl of cholesterol in solution with lower detection limit of 50mg/dl and shelf life of about 2 months when stored at 4 degrees C.
authors.affiliation: Biomolecular Electronics and Conducting Polymer Research Group, National Physical Laboratory, Dr. K.S. Karishnan Marg, New Delhi 110012, India; Department of Chemistry, University of Delhi, Delhi 110007, India.
authors.forename: Sunil K
authors.initials: SK
authors.lastname: Arya
authors.forename: Pratima R
authors.initials: PR
authors.lastname: Solanki
authors.forename: Ravindra P
authors.initials: RP
authors.lastname: Singh
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