Polypyrrole-based potentiometric biosensor for urea: Part 2. Analytical optimisation

✍ Scribed by S.B. Adeloju; S.J. Shaw; G.G. Wallace

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 606 KB
• Volume: 281
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(93)85023-d

✦ Synopsis

A novel potentiometric biosensor for urea, based on the entrapment of urease into a polypyrrole film, has been developed via galavanostatic film formation. The electrochemical polymerization was achieved by the application of a current density of 0.5 mA cm-* to a working platinum disc electrode for 3 mitt in a solution containing 0.5 M pyrrole and 4000 pg ml-' urease. The optimum conditions for the reliable performance of this sensor were 1 mM phosphate buffer at pH 7.0 and 35°C. A Nemstian response was observed for increasing concentration of urea in the linear range of 0.5 to 100 mM. Trace concentrations of Hg2+ and K+ were both found to inhibit the response of the biosensor.