Determination of vancomycin in plasma by RP-HPLC

Aim To establish an RP-HPLC method for determination of vancomycin plasma level.Methods Tinidazole was used as internal standard.The vancomycin in plasma is extracted by the sedimentation with 30% zine sulfate,Liquid chromatography was performed on Kromasil C18 column(150 mm×4.6 mm,5 μm),with a mobile phase of methanol and potassium dihydrogen phosphate buffer solution(20∶80),and an elution rate of less than 0.8 ml·min-1.The injection volume was 20 μl,the column temperature was 30℃ and the detection wavelength was 236 nm.The sensitivity was 0.02 AUFs.The experiment data were calculated by peak area and internal standard method.Results A linearity was obtained within the range of vancomycin concentrations from 5 to 80μg·ml-1(r=0.998 5,n=5),the inspect limitation was 2.5 μg·ml-1(S/N≥3),and the intra-day and inter-day RSD were less than 10%.The stable inspection RSD was less than 10%.Conclusion It appears to be a rapid,convenient and accurate method for determination of the vancomycin concentrations in plasma.