Very High-Speed Liquid Chromatography III: Quantitative Analysis of Parabens in Cosmetic Products

Abstract
A very rapid quantitative method for analyzing methylparaben and propylparaben in cosmetic products, based on recently developed very high-speed liquid chromatography, is described. The method involves sample solubilization in THF/ethanol mixtures, addition of butylparaben as an internal standard, and filtration followed by liquid chromatographic analysis. Total sample preparation and analysis time is six minutes. The actual chromatography is completed in one minute. Precision of the method is better than 1% relative standard deviation. The detection limits for methylparaben are approximately 200 pg using UV detection at 254 nm. This method offers significant advantages in sensitivity, precision, and sample throughput compared to previous analytical procedures.