A modified nanocomposite biosensor for quantitative l-glutamate detection in beef

Meat Sci. 2020 Oct:168:108185. doi: 10.1016/j.meatsci.2020.108185. Epub 2020 May 30.

Abstract

A new biosensor for detecting l-glutamate (l-Glu) in beef was developed. Firstly, a bare Au electrode was surface-modified by gold nanoparticles (Au NPs), graphene oxide (GO), and chitosan (CS) as immobilized materials, and then its surface was connected with l-glutamate oxidase (GluOx). The modified Au NPs/GO/CS electrode was characterized by scanning electron microscopy, and the formation mechanism was elaborated. The response current of the l-Glu biosensor maximized to 0.08 mA at pH 7.5 and 0.09 mA at 30 °C, with a detection range of 0.2-1.4 mM and a detection limit of 0.023 mM. The l-Glu biosensor had high accuracy, and its results linearly fitted with those of the amino acid analyzer with a coefficient of 0.996. The l-Glu biosensor had high selectivity, repeatability, and stability and detected higher l-Glu content in the cooked beef than in the raw beef.

Keywords: Beef; Biosensor; Glutamate oxidase; Quantitative detection; l-Glutamate.

MeSH terms

  • Amino Acid Oxidoreductases / chemistry
  • Animals
  • Biosensing Techniques / instrumentation*
  • Cattle
  • Chitosan / chemistry
  • Cooking
  • Glutamic Acid / isolation & purification*
  • Gold / chemistry
  • Graphite / chemistry
  • Nanocomposites
  • Red Meat / analysis*

Substances

  • graphene oxide
  • Glutamic Acid
  • Gold
  • Graphite
  • Chitosan
  • Amino Acid Oxidoreductases
  • L-glutamate oxidase