A highly sensitive electrochemical biosensor based on zinc oxide nanotetrapods for L-lactic acid detection

Nanoscale. 2012 Jun 7;4(11):3438-43. doi: 10.1039/c2nr30334e. Epub 2012 Apr 27.

Abstract

An amperometric biosensor based on zinc oxide (ZnO) nanotetrapods was designed to detect L-lactic acid. The lactate oxidase was immobilized on the surface of ZnO nanotetrapods by electrostatic adsorption. Unlike traditional detectors, the special four-leg individual ZnO nanostructure, as an adsorption layer, provides multiterminal charge transfer channels. Furthermore, a large amount of ZnO tetrapods are randomly stacked to form a three-dimensional network naturally that facilitates the exchange of electrons and ions in the phosphate buffer solution. Utilizing amperometric response measurements, the prepared ZnO nanotetrapod L-lactic acid biosensor displayed a detection limit of 1.2 μM, a low apparent Michaelis-Menten constant of 0.58 mM, a high sensitivity of 28.0 μA cm(-2) mM(-1) and a good linear relationship in the range of 3.6 μM-0.6 mM for the L-lactic acid detection. This study shows that the biosensor based on ZnO tetrapod nanostructures is highly sensitive and able to respond rapidly in detecting lactic acid.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biosensing Techniques*
  • Electrochemical Techniques
  • Electrodes
  • Fluorocarbon Polymers / chemistry
  • Gold / chemistry
  • Lactic Acid / analysis*
  • Nanostructures / chemistry*
  • Zinc Oxide / chemistry*

Substances

  • Fluorocarbon Polymers
  • Lactic Acid
  • perfluorosulfonic acid
  • Gold
  • Zinc Oxide