Platinum nanoparticles-doped sol-gel/carbon nanotubes composite electrochemical sensors and biosensors

Biosens Bioelectron. 2006 Jan 15;21(7):1125-31. doi: 10.1016/j.bios.2005.04.009.

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.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Biosensing Techniques / instrumentation*
  • Biosensing Techniques / methods
  • Coated Materials, Biocompatible / chemistry
  • Electrochemistry / instrumentation*
  • Electrochemistry / methods
  • Enzymes, Immobilized / chemistry
  • Equipment Design
  • Equipment Failure Analysis
  • Glucose / analysis*
  • Glucose / chemistry
  • Glucose Oxidase / chemistry*
  • Hydrogen Peroxide / analysis*
  • Nanotubes, Carbon / chemistry*
  • Ointments
  • Particle Size
  • Phase Transition
  • Platinum / chemistry*
  • Transducers

Substances

  • Coated Materials, Biocompatible
  • Enzymes, Immobilized
  • Nanotubes, Carbon
  • Ointments
  • Platinum
  • Hydrogen Peroxide
  • Glucose Oxidase
  • Glucose