Automated fluorometric analysis of calcium pantothenate in multivitamin preparations

An automated fluorometric procedures is described for assaying calcium pantothenate in multivitamin preparations. Sample extracts containing calcium pantothenate are treated on-line with a slurry of magnesium trisilicate which removes any interfering riboflavin that may be present. The filtrate is resampled, mixed on-line with a slurry of Dowex 50W-X4 (H+) which removes any interfering beta-alanine that may be present, and dialyzed. Dialysates are hydrolyzed in an alkaline medium and reacted with a mixture of o-phthalaldehyde and 2-mercaptoethanol in boric acid solution. The fluorescence intensity due to the formation of a fluorogenic compound is measured at 455 nm after excitation at 350 nm. The procedure developed is capable of analyzing 20 samples/hr. Analytical data indicate that calcium pantothenate is assayed reliably both from real and synthetic multivitamin preparations. The mean recovery of calcium pantothenate added to sample solutions of tablet composites was 95.4%.