Long-optical-path thin-layer spectroelectrochemical flow cell with inexpensive gold electrodes

A novel long-optical-path thin-layer spectroelectrochemical cell for flow s ystems is described and its suitability for in situ UV-visible applications , demonstrated. Gold electrodes with flat surface are simply cut from stand ard recordable CDs of the gold sputtered type. After removal of the protect ing polymer layer, the area of the working and auxiliary coplanar electrode s is delineated by scraping off the gold layer. A set of twin electrodes is placed face to face within any standard spectrophotometric cuvette with 1. 0 cm optical path. The sample is introduced with a syringe or peristaltic p ump and reaches the bottom of the working electrodes through a PTFE tube. E valuation was done with o-tolidine in acidic medium as a model system, and gave good results under stationary conditions and in the FIA mode. The appr opriateness of the tell for flow operation including FlA, good potential co ntrol, simplicity of construction and maintenance, easy adaptability to exi sting instrumentation and a cost lower than any other proposed model are ad vantages of the innovative cell design.