Effect of surface-active agents on amperometric NADH measurements with chemically modified electrodes

✍ Scribed by Géza Nagy; Imre Kapui; Lo Gorton

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 906 KB
• Volume: 305
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)00342-j

✦ Synopsis

A special electrochemical pretreatment was employed in the case of finely polished glassy carbon electrode surfaces to increase the adsorption of the redox mediator Meldola blue (7-dimethylamino-1,2-benzophenoxazine).

The chemically modified glassy carbon electrode holding the adsorptive mediator layer was used to measure the NADH concentration amperometrically. The interfering effect of non-ionic surfactants was studied for NADH measurements using a rotating disc electrode technique and flow injection measurements. The glassy carbon electrode response was less affected and could be regenerated much more easily than the response of a similar spectrographic graphite based electrode, studied earlier. Surface active agents can influence the apparent coverage of the surface by the mediator.