Sample preparation for CE-DAD analysis of the water soluble vitamins in food products

The capillary electrophoretic separation of six water-soluble vitamins (thiamine, nicotinic acid, nicotinamide, d-pantothenic acid, pyridoxine and ascorbic acid) was studied. Four CE backgrounds electrolytes were optimized and the most suitable ones were applied for investigation of analytes in real samples (yeast, beer, syrups). Several extraction procedures were performed in order to extract vitamins from proteins and phosphate groups. The research showed that it is possible to minimize interference from the solution with a complex composition and overcome the problem of peak overlapping by exchanging separation BGEs. Moreover, the second order data generated by CE-DAD instrument and Chemstation software (Agilents Technologies) were used to check of the peak purity.