L-ASCORBIC-ACID DETERMINATION IN FRUITS AND MEDICAL FORMULATIONS BY ION INTERACTION REAGENT REVERSE PHASE HPLC TECHNIQUE

The content of L-ascorbic acid has been evaluated in juices of fruits and in typical medical formulations. Grapefruits, orange, lemon and kiwi, as well as tablets of vitamin C and antipyretic medicine added with vitamin C have been analyzed. The ion interaction reagent reverse phase HPLC chromatographic technique has been employed, making use of octylaminium salicylate as interaction reagent and of a C-18 spherical 5 μ m column as stationary phase. Sensitivity levels of the order of 100 pmoles can be obtained. The dependence on time and temperature of the oxidation processes which L-ascorbic acid undergoes during its preservation has also been studied.