Abstract: A high performance liquid chromatography (HPLC) method for the detection of content of fatty acids in amino acid-based surfactants was established.Separation is performed by a Welch Ultimate AQ-C₁₈ column (250 mm×4.6 mm,5 μm) with acetonitrile-0.1% formic acid aqueous solution as the mobile phase for gradient elution.After acidification and derivatization,the sample is detected with a UV and visible light wavelength variable detector (VWD).Results show that,all linearity ranges of the fatty acids are within 5-500 mg/L with the correlation coefficients greater than 0.999.The spiked recoveries vary from 93.2%-103.0%.The limits of determination and quantification are 0.03% and 0.1%,respectively.The method is simple,time-saving and precise,which may be suitable for fatty acids determination in amino acid-based surfactants.

Key words: amino acid-based surfactant, high performance liquid chromatography, fatty acids