Comparison of two types of mobile phases for the determination of B vitamins by thin layer chromatography

Abstract

Thin-layer chromatography (TLC) has been used to study the infl uence of a number of factors (the nature of the stationary phase, the nature and concentration of the organic solvents and surfactants, the pH of the buff er solution) on the chromatographic characteristics of B vitamins: B1 (thiamine), B6 (pyridoxine), B12 (cyanocobalamin). The stationary phases were plates with polar (Sorbfi l on a polymer (highperformance plates, HTLC) and aluminum substrates), weakly polar (Polyamide-6), and nonpolar (RP-18 on an aluminum substrate) sorbents. As micellar mobile phases – micellar solutions of cetylpyridinium chloride in the concentration range 5–10-4 – 5–10-1 M, sodium dodecyl sulfate in the concentration range 2,5–10-4 – 5–10-1 М. It has been established that among aqueous-organic mobile phases (MF) the best results have been obtained for MF of the composition acetonitrile – water (15:385) on polar high-performance plates. More eff ective than acetonitrile – water is the PF of the composition acetonitrile – cetylpyridinium chloride (15:85) in the presence of a phosphate buff er solution with pH = 3. For the last PF, TLC determination of vitamins B1 , B6 , B12 in pharmaceutical preparations with a Sr value of interval 0.01–0.06 has been developed.

Keywords

• vitamins b
• thin layer chromatography
• organic solvents
• phosphate buff er solution
• micellar mobile phases