Application of LC and HPTLC-densitometry for the simultaneous determination of two multicomponent mixtures containing pyridoxine hydrochloride and cyanocobalamine

Abstract

Two methods were presented for the simultaneous determination of two multicomponent mixtures containing pyridoxine hydrochloride (B 6) and cyanocobalamine (B 12) with benfotiamine (BN) [mix. 1], or thiamine nitrate (B 1) and diclofenac sodium (DC) [mix. 2]. The first high-performance liquid chromatographic (HPLC) method depends on the use of a cyanopropyl column at a flow rate of 1.5 mL min-1 with a mobile phase consisting of acetonitrile-25 mM ammonium acetate, pH 3.7 (10:90, v/v), for mix. 1 or acetonitrile-25 mM ammonium acetate, pH 5.0 by gradient elution, changing the proportion of the system linearly with a time schedule program, for mix. 2. Quantitation was achieved by UV detection at 220 nm. The second method was based on HPTLC separation followed by densitometric measurement of the spots at 254 nm. The separation was achieved on HPTLC silica gel F 254 plates using chloroform-ethanol-water-acetic acid (5:8:2:0.5, v/v/v/v) for mix. 1 and chloroform-ethanol-water-acetic acid (1.5:8:2:0.5, v/v/v/v) for mix. 2. The proposed methods were successfully applied for the analysis of pharmaceutical formulations containing the two multicomponent combinations.