A novel electrochemical glucose biosensor based on a poly (L-aspartic acid)-modified carbon-paste electrode

Abstract

A new amperometric biosensor was fabricated by means of electropolymerization of L-aspartic acid on a carbon-paste electrode (CPE) for the bioelectrochemical determination of glucose. The electropolymerization process was conducted via cyclic voltammetry (CV). The modified CPE with poly (L-aspartic acid) (PAA) provided free carboxyl groups so as to immobilize the glucose oxidase (GOx), and further, enhanced the electrocatalytic activity of the hydrogen peroxide (H₂O₂). The biosensor displayed both good stability and good bioactivity. The sensitivity of the prepared biosensor was 5.3 µA cm⁻²mM⁻¹. Its linear range extended from 0.05 mM to 1.0 mM, with the low limit of detection (LOD) being 69.2 µM. The Michaelis–Menten constant was found to be 1.17 mM. Furthermore, the biosensor showed good anti-interference ability in relation to dopamine, uric acid, and ascorbic acid. Taken together, these results demonstrate that PAA/CPE is a promising material for the fabrication of glucose biosensor.

Keywords:

• Poly-L-aspartic acid
• glucose biosensor
• carbon paste electrode
• glucose oxidase

Disclosure statement

The authors declare no conflict of interest. Neither ethical approval nor informed consent was required for this study.