An Improved and Validated LC Method for Resolution of Panthenol

An improved LC method was developed and validated for determination of enantiomeric purity of panthenol in bulk drugs. The method is based on derivatization of panthenol with 3,5-dinitrobenzoyl chloride. Baseline separation with resolution >2.7 was achieved within 20 min on Kromasil CHI-DMB (250 × 4.6 mm) column using n-hexane:ethanol (95:5 v/v) as mobile phase at a flow rate of 1.5 mL min^?1. The analytes were detected by their UV absorbance at 265 nm. The effects of ethanol, 2-propanol and temperature on enantioselectivity and resolution of enantiomers were evaluated. The method was extensively validated and proved to be robust. The recoveries were between 98.3 and 101.4% with <1.6% relative standard deviation. The regression equations for the derivatives of d-panthenol and l-panthenol were y ₁ = 18.01x ₁ ? 32.56 (r ₁ ²  = 0.9984) and y ₂ = 17.855x ₂ ? 28.16 (r ₂ ²  = 0.9990), respectively. The LOD and LOQ for the derivative of d-panthenol were 10.6 and 37.4 μg mL^?1 and for the derivative of l-panthenol were 12.1 and 40 μg mL^?1, respectively. The improved method was found to be simple, rapid, and sensitive for the determination of enantiomeric purity of panthenol in bulk drugs.