Development of a HPLC method for the simultaneous determination of several B-vitamins and ascorbic acid.

In cognizance of the difficulties involved in the colorimetric and titrimetric methods for the determination of individual vitamins, this laboratory has been carrying out a series of studies into the use of HPLC for improved analysis of these nutrients. Preliminary studies have been carried out for the determination of four B-vitamins. The present paper reports on further improvements made to enable the simultaneous determination of eight vitamins i.e. B1, B2, B6, B12, C, niacin, niacinamide and folic acid. Trials were carried out to determine the most suitable chromatographic system include changing the proportion of methanol in the mobile phase, the use of different ion-pairing reagents and other additives such as triethylamine and ammonia. Three sets of HPLC mobile phase systems are proposed to enable successful separation of all eight vitamins in less than 20 minutes, varying slightly with the type of ion-pairing reagent and mobile phase additive. This laboratory is currently carrying out trials to determine if the developed methods could be used for the determination of pharmaceutical products and food samples.