Fluorometric Determination of Folic Acid Based on Its Reaction With The Fluorogenic Reagent Fluorescamine

Abstract A spectrofluorimetric analysis of folic acid (pteroylglutamic acid) using fluorescamine as a fluorogenic reagent, has been developed. The analytical parameters for optimal reaction and sensitivity (pH, fluorescamine concentration, temperature, reaction time), have been studied. The present method may be employed for the analysis of small amounts of folic acid (< 20 ppb), without interferences from other compounds; the selectivity being increased by the application of the synchronous derivative technique to normal fluorescence spectra. The minimum detectable quantity, using the latter technique, is estimated to be 16 ppb, with a relative standard deviation of 2.7 % (10 determinations). A soft sport beverage, containing low concentrations of the vitamin, have been satisfactorily analyzed.