Novel HPTLC and UV-AUC analyses: For simple, economical, and rapid determination of Zileuton racemate

Abstract

Novel, simple, rapid and reliable High-Performance Thin-Layer Chromatographic (HPTLC) and UV-spectroscopic area under curve (UV-AUC) methods were developed and validated for the analysis of zileuton racemate in bulk and in in-house tablet formulation. HPTLC quantitation of zileuton was done by UV detection at 260nm and analysis was performed on (20×10cm) aluminium sheets precoated with silica gel 60-F254 (E. Merck) as stationary phase and toluene–methanol–glacial acetic acid (3.5:1.5:0.1 v/v) as mobile phase. Quantitation by HPTLC method was performed over the concentration range of 200–1200ng/band. The HPTLC method resulted into a compact and well resolved band for zileuton at retention factor (Rf) of 0.51±0.02. Linear regression analysis data for calibration of HPTLC method represented a good linear relationship with regression coefficient; r2=0.997. UV-AUC method was developed using sodium lauryl sulphate (0.05M) as a hydrotropic agent to enhance water solubility and area was determined at a wavelength range in between 248.40 and 271.0nm. Correlation coefficient for UV-AUC analysis was found to be r2=0.999. The developed UV-AUC method depicted a fine linear relationship for zileuton racemate in a concentration range of 2–12μg/mL. Both the developed methods were validated for precision, robustness, ruggedness, accuracy, sensitivity as per guidelines laid by the International Conference on Harmonisation (ICH). Statistical analysis proved that the developed methods were precise, robust, sensitive and accurate and can be used effectively for the analysis of zileuton in bulk and pharmaceutical formulations.