Authors: Amelia Tero-Vescan 1, Silvia Imre 2*, Camil-Eugen Vari 3, Anamaria Toma 2, Bianca-Eugenia Ősz 3
Affiliation: Faculty of Pharmacy, University of Medicine and Pharmacy Tîrgu Mureș, Romania
1 Department of Biochemistry. Chemistry of Environmental Factors
2 Department of Analytical Chemistry and Drug Analysis
3 Department of Pharmacology and Clinical Pharmacy
Background. Vitamins are the most commonly used active ingredients in dietary supplements (DS), and the quality of DS is subject to highly permissive legislation.
Aims. The purpose of this study was to underline the risks associated with sub- and overdosing of water-soluble vitamins in the case of performance and amateur athletes who use vitamins as dietary supplements without professional counseling and to test the quality of vitamins as DSs or drugs marketed in pharmacies through a new simple and rapid HPLC method.
Methods. Vitamins were analyzed by HPLC using a Phenomenex Luna C18 column, 3 μm, 150 x 4.6 mm, a mobile phase with 100 mM ammonium acetate (pH = 5.8) – acetonitrile – methanol in a concentration gradient from 88:5:7 to 68:25:7 in 10 minutes with 1 ml/min flow rate. Sample processing: the vitamins from the tablets were extracted in 15 mM phosphoric acid and the injectable solutions diluted with 15 mM phosphoric acid prior to chromatographic analysis.
Results. The risk of overdosing water-soluble vitamins is highly questionable, but the under-dose intake is related to their use in the case of athletes, these vitamins being involved in energy metabolism. Hence the importance of the quality of commercial products with these vitamins. The proposed HPLC method allows the separation of ascorbic acid, folic acid, thiamine, pyridoxine, nicotinamide, cyanocobalamin and riboflavin. The linearity of the analytical method was tested and applied for five vitamin assays in tablets and injectable solutions purchased from the pharmacy, which were quantitatively analyzed, and the results were compared with those declared by the manufacturer.
Conclusions. Permissive legislation on DS implicates acquiring them from “safe” sources such as community pharmacies, especially for amateur athletes who do not benefit from specialized nutritional counseling.