RESUMEN
A method was developed for the determination of sodium caprylate in human serum albumin by reversed phase high performance liquid chromatography(RP-HPLC) after pre-column derivatization. The caprylic acid, extracted from human serum albumin by hexane, was treated with ω-bromoacetophenone and 18-crown-6 for 30 min at 50 ℃, and analyzed on a Nova-Park C_(18)(150 mm×3.9 mm, 4 μm) column with methanol-water(75∶ 25, V/V) as the mobile phase. The internal standard was enanthic acid, the flow rate was 1.0 mL/min and the detection wavelength was 262 nm. The extraction yield of caprylic acid was 97.9% and that of enanthic acid was 98.2%. The linear range of sodium caprylate was 9.00×10~(-4)-1.44×10~(-2) mol/L(r=0.9995). The average recovery of caprylic acid was 99.7%, RSD was less than 0.9%. The present method is reliable and relatively simple and can be used for the determination of sodium caprylate in human serum albumin.