An optimized method for the simultaneous determination of vitamins B1, B6, B12, in multivitamin tablets by high performance liquid chromatography

A simple, precise, rapid and selective HPLC-RP method has been developed for the simultaneous determination of thiamine hydrochloride (B-1) 150 mg, pyridoxine hydrochloride (B-6) 150 mg, and hydroxocobalamine chloride (1312) 0.150 mg in multivitamin tablets. The method uses a Hypersil-BDS C-18 reversed phase column and gradient elution. The aqueous mobile phase contained 0.015% triethylamine adjusted to pH 2.7 with 1 N sulfuric acid and acetonitrile. Separation and quantitation was achieved by changing the proportion of the system linearly with a time-schedule programme. Detection was carried out using a dual-beam UV detector set at 280, 350 nm. Good linearity was observed between the concentration of the analytes and peak area (r = 0.9999, 0.9998). Sample preparation was relatively simple whereas excipients present in the dosage forms did not interfere with the peaks of interest. Recovery of the compound from the B-1, B-6, B-12 was quantitative. (C) 2002 Elsevier Science B.V. All rights reserved.