ABSTRACT

The electrochemical properties of folic acid were investigated in pH range 1.0-9.0 by cyclic, linear sweep and adsorptive stripping voltammetry. The compound was irreversibly oxidized at an anodically pre-treated boron-doped diamond electrode in one or two oxidation steps, wliich are concentration- and/or pH-dependent. Using square-wave stripping mode, folic acid yielded well-defined voltammetric responses inboüi 0.1M percliloric acid and 0.1M Britton-Robinsonbuffer, pH 6.0 with lünits of detection 0.035 |xg/mL (7.93 10'8 M) and 0.14 |xg/mL (3,2xl0'7 M), respectively, after an accmnulation of 120 s at open-circuit condition. Practical applicability of the newly developed approach was verified by the direct assays of tablet dosage fonns.