Validation of HPLC stability-indicating method for Vitamin C in semisolid pharmaceutical/cosmetic preparations with glutathione and sodium metabisulfite,as antioxidants

摘要

HPLC stability-indicating method was validated for Vitamin C (ascorbic acid) in semisolid pharmaceutical/cosmetic formulations containing glutathione and sodium metabisulfite,as antioxidants.The described procedure included a reliable,precise,accurate and specific method determination employing a 250mm x 4.6mm C18 column,0.2% metaphosphoric acid/methanol/acetonitrile (90:8:2,v/v/v) as the mobile phase and detection at 254 nm.Nicotinic and ascorbic acids were employed as standards,both presenting purity of 99.0%.Linearity was established for the ascorbic acid concentrations ranging form 1.0 to 12 mu g mL-1,accuracy/recovery percentage was 95.46-101.54%,precision values were 0.38 (intra-day) and 1.22% (inter-days),and LOD and LOQ were found to be 0.05 and 0.17 mu g mL-1,respectively.The working mobile phase elevated the ascorbic acid retention time to ~3.5min at a flow rate of 1.0 mL min-1 and provided resolution of the active from the nicotinic acid (internal standard),degradation product (oxalic acid) and other excipients from the pharmaceutical/cosmetic preparations.