Voltammetric analysis of glucose using poly 4-vinylpyridine modified carbon fiber electrode

Abstract

An enzyme-modified microelectrode has been constructed and evaluated. The 4-vinlypyridine was polymerized anodically at its optimum onto a carbon fiber (8 µm diameter) when its concentration was 0.003 M, pH 3.0, scan rate 50 mV s⁻¹ and at a constant potential of +0.40 V vs. SCE. Initial investigation indicated that the type of supporting electrolyte and solvent used affected this polymerization. Glucose oxidase was then dip-coated onto the polymer modified electrode for glucose determination. The dip-coating enzyme immobilization technique has produced the best current response. The glucose analysis was only done in vitro for a whole blood sample. The effects of common interferents in glucose determination are also reported. The operational life of the electrode spanned over two weeks of constant use under normal laboratory condition. The in-vivo glucose analysis has yet to be done but preliminary work on this looked very promising. This topic will be discussed in future articles.

Keywords:

• Glucose
• Microelecrode
• Polymer

Acknowledgements

We are very grateful to Professor R.M. Wightman from the Department of Chemistry, University of North Carolina at Chapel Hill, North Carolina, USA for his advice on this work.

We are also indebted to the Malaysian Government for financial support under Intensified Research in Priority Areas, Grant No. 09-02-05-6028.