Abstract
Platinum nanoparticle-doped chitosan (CHIT) solution can be easily prepared by treating the CHIT solution with aqueous H 2PtCl 6 solution followed by chemical reduction of Pt(IV) with NaBH 4. Multiwalled carbon nanotubes (MWCNT) are then dispersed in the nanoparticle-doped solution. The resulting Pt-CNT-CHIT material brings new capabilities for electrochemical devices by using the synergistic action of Pt nanaoparticles and CNT. Positively charged Pt-CNT-CHIT solution and negatively charged poly(sodium- p-styrenesulfonate) salt (PSS) have been employed to fabricate stable ultrathin multilayer films on gold electrode and quartz glass slides in a layer-by-layer fashion. Cyclic voltammetric and UV–vis adsorption spectroscopy confirms the consecutive growth of the multilayer films. The modified gold electrode allows low-potential detection of hydrogen peroxide with high sensitivity and fast response time. With the immobilization of cholesterol oxidase onto the electrode surface using glutaric dialdehyde, a biosensor that responds sensitively to cholesterol has been constructed. In pH 6.98 phosphate buffer, almost interference free determination of cholesterol has been realized at 0.1 V vs. SCE with a linear range from 0.01 to 3 mM and response time<30 s. With the immobilization of another cholesterol esterase enzyme layer, the biosensor was used to determine total cholesterol in serum samples with satisfactory results.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call