The mobile phase which was properly filtered with Whatman No. 1 filter paper before use consisted of a mixture of buffer (hexane-1-sulphonic acid Na salt + KH2PO4 + HPLC water + 5 ml TEA, pH 3.0 with H2PO4) and methanol in the ratio
of 80:20. Chromatogram of mixed standard vitamins was obtained by running different concentrations