High pressure liquid chromatographic quantitation of teicoplanin in human serum

A reverse phase high-pressure liquid chromatographic method to assay teicoplanin in serum is described. The procedure involves a single protein precipitation step with acetonitrile containing the internal standard mephenesin, followed by direct injection of the supernatant into the chromatograph. This HPLC method has good linearity, precision, recovery and sensitivity over the range of serum concentrations observed with the recommended dosages of the drug (5-50 mg/l). The assay has been validated by a correlation study with a bioassay on 97 sera obtained from patients treated with teicoplanin (r = 0.9519, P less than 0.001). The small serum sample size (100 microliters) and the use of a common C18 column make this assay ideal for drug monitoring, provided that HPLC equipment is available.