FLOW-INJECTION SPECTROFLUOROMETRIC DETERMINATION OF FLUORIDE OR PHOSPHATE BASED ON THEIR INHIBITORY EFFECT ON THE PHOTOOXIDATION OF ACRIDINE CATALYZED BY IRON(III)

An automated procedure for the photochemical determination of fluoride or phosphate has been developed, based on the inhibitory effect of th ese anions on the photo-oxidation of acridine in the presence of iron( III). The development of the photochemical reaction was monitored by m aking use of the fluorescence of acridine. Linear calibration graphs m ere obtained over the ranges 0.76-9.5 mu g ml(-1) for fluoride and 0.9 5-9.5 mu g ml(-1) for phosphate, The method was applied to the determi nation of fluoride and phosphate in waters.