A New Chromium(III) Microelectrode Based on Self-Assembled Diethylenetriamminepentaacetic Acid-Poly(fuchsin basic) Modified Electrode

A new selective, sensitive, and rapid response microelectrode for microamount chromium(III) determination was developed. For the electrode preparation, fuchsin basic was electropolymerized onto a carbon microdisk electrode., and then diethylenetriamminepentaacetic acid (DTPA) was self-assembled oil the electrode surface by the reaction between DTPA and poly(fuchsin basic). The determination conditions were optimized. The electrode showed a linear response to Cr3+ ions in the concentration range of 1.0 x 10(-6) - 1.0 x 10(-4) M and exhibits a super-Nernstian slope of 32.5 +/- 0.4 mV per decade. The detection limit is 3.6 x 10(-7) M. The response time of the electrode is less than 10 s, and it can be used for at least 2 months with limited considerable divergences in its potentials. The proposed electrode was applied for monitoring the chromium ion level in wastewater of chromate industries.