ADSORPTIVE STRIPPING VOLTAMMETRY OF RIBOFLAVIN AND OTHER FLAVIN ANALOGS AT THE STATIC MERCURY DROP ELECTRODE

Controlled adsorptive accumulation of riboflavin, flavin mononucleotide (FMN), and alloxazine on the static mercury drop electrode provides the basis for the direct stripping measurements of these compounds in the nanomolar concentration level. Differential pulse voltammetry, following 30-min preconcentration, yields a detection limit of 2. 5 multiplied by 10** minus **1**1 M riboflavin. The adsorptive stripping response is evaluated with respect to experimental parameters such as preconcentration time and potential, bulk concentration, stirring rate, presence of surfactants, and others. The relative extent of adsorption and the resulting response are rather sensitive to the composition of the side chain of the flavin compound.