Simultaneous determination of four drugs for kidney diseases in urine by high performance liquid chromatography

A high performance liquid chromatographic (HPLC) method was proposed for the simultaneous determination of four drugs for kidney disease, enalapril, triamterene, furosemide and valsartan. After proteins being removed by acetone precipitation method, freeze drying and redissolving in mobile phase, the urine samples were analyzed by HPLC. Chromatographic separation was performed on a WondaSil C18-WR (150 mm x 4.6 mm, 5 mu m) in gradient elution mode using 10.0 mmol/L ammonium acetate aqueous solution (pH 3.90) and acetonitrile as mobile phases at a flow rate of 1.0 mL/min. The detection wavelength was set at 254 nm. Under the optimized conditions, good linearities were obtained in the range of 0.15-300 mg/L, 0.05-100 mg/L, 0.75-750 mg/L, 0.05-100 mg/L, and the detection limits were 1.38 x 10(-2), 7. 67 x 10(3), 3.69 x 10(-2), 1. 16 x 10(-2) mg/L for enalapril, triamterene, furosemide and valsartan, respectively. The recoveries were in the range of 89.49%-99.20% with the relative standard deviations (RSDs) among 4.12%-9.44%. The method is simple, accurate and effective, and the results showed the method is applicable for the analysis of the four drugs for kidney diseases in real urine samples.