T. Perezruiz et al., PHOTOCHEMICAL SPECTROPHOTOMETRIC DETERMINATION OF RIBOFLAVIN AND RIBOFLAVIN 5'-PHOSPHATE BY MANUAL AND FLOW-INJECTION METHODS, Analyst, 119(6), 1994, pp. 1199-1203
The sensitizing effect of riboflavin (RF) and riboflavin 5'-phosphate
(FMN) on the photo-oxidation of dianisidine was studied. The rate of t
he photochemical reaction was monitored spectrophotometrically at 460
nm. The method allows the determination of RF and FMN in the range 1 X
10(-7)-5 x 10(-6) mol dm(-3) with a relative standard deviation of ab
out 0.68%. The method can be successfully adapted to flow injection. M
anual and flow injection methods were satisfactorily applied to the de
termination of RF or FMN in fortified breads and pharmaceutical prepar
ations. A possible mechanism for the sensitized photoreaction is propo
sed.