DETERMINATION OF FOLIC-ACID IN AN ELEMENTAL DIET BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH UV DETECTION

Determination of folic acid (550 ng/g) in an elemental diet containing 46 compounds at concentrations at least 0.02 . 10(6) times higher than that of folic acid was performed by high-performance liquid chromatography with ultraviolet detection at 360 nm using acetonitrile-water (pH 2.1, adjusted with phosphoric acid) (9:91) with the addition of 1 mM ethylenediaminetetraacetic acid disodium salt as the mobile phase. This method is suitable for the determination of folic acid in an elemental diet, because it is simple, rapid, sensitive and reproducible. The calibration graph was linear in the range 0-0.6 mug. Recovery of folic acid was about 95% by the standard addition method. There was good agreement between the indicated and found folic acid concentrations.