title: Platinum nanoparticles-doped sol-gel/carbon nanotubes composite electrochemical sensors and biosensors.
abstract: Platinum nanoparticle-doped sol-gel solution is prepared and used as a binder for multi-walled carbon nanotubes (CNT) for the fabrication of electrochemical sensors. Amine group containing sol-gel solution is selected to utilize the affinity of -NH(2) groups toward metal nanoparticles for stabilization the nanoparticles in solution. The resulting CNT-silicate material brings new capabilities for electrochemical devices by using the synergistic action of the electrocatalytic activity of Pt nanoparticles and CNT. The combined electrocatalytic activity permits low-potential detection of hydrogen peroxide with remarkably improved sensitivity. With the incorporation of glucose oxidase within the Pt-CNT-silicate matrix, a Pt-CNT paste-based biosensor has been constructed that responds more sensitively to glucose than CNT-based biosensor. The influences of the composite of the sol-gel solution, the quantity of the solution and the Pt nanoparticles loading are examined. In pH 6.98 phosphate buffer, almost interference free determination of glucose is realized at 0.1 V versus SCE with a linear range from 1 to 25 mM, a response time <15s, and the sensitivity is 0.98 microA mM(-1)cm(-2). The sensitivity of the Pt-CNT paste-based biosensor is almost four times larger than that of the CNT-based biosensor (0.27 microA mM(-1)cm(-2) at 0.1 V). The improved electrocatalytic activity and surface renewability made the Pt-CNT-silicate system a potential platform to immobilize different enzymes for other bioelectrochemical applications.
authors.affiliation: Chemistry and Chemical Engineering College, State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Hunan, Changsha 410082, PR China.
authors.forename: Minghui
authors.initials: M
authors.lastname: Yang
authors.forename: Yunhui
authors.initials: Y
authors.lastname: Yang
authors.forename: Yanli
authors.initials: Y
authors.lastname: Liu
authors.forename: Guoli
authors.initials: G
authors.lastname: Shen
authors.forename: Ruqin
authors.initials: R
authors.lastname: Yu
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005947:Glucose / Q000032:analysis* / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009824:Ointments; D010316:Particle Size; D044367:Phase Transition; D010984:Platinum / Q000737:chemistry*; D014159:Transducers
chemical_list: D020099:Coated Materials, Biocompatible; D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D009824:Ointments; D010984:Platinum; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D005947:Glucose