Determination of vitamin C in sea urchin: Comparison of two HPLC methods

A UV-detection and a fluorimetric-detection HPLC method were compared for t he determination of ascorbic acid levels in sea urchin gonad. The UV detect ion method (direct determination of ascorbic acid at 245 nm) gave a detecti on limit of 0.19 mug mL(-1) and reproducibility (6 assays of a sea urchin g onad sample) of 6.35%. The fluorimetric detection method (oxidation of asco rbic acid to dehydroascorbic acid, treatment with 1,2-phenylenediamine to c onvert the dehydroascorbic acid to a fluorescent product,and fluorimetric d etection of the product) gave a detection limit of 0.082 mug mL(-1) and rep roducibility of 0.61%. The fluorimetric method is thus preferable for deter mination of vitamin C in sea urchin gonad.