SEPARATION AND DETERMINATION OF 5 PENICILLINS BY REVERSED-PHASE HPLC

Rapid separation and quantitative determination of mixtures of amoxici llin, ampicillin, benzylpenicillin, cloxacillin and dicloxacillin was investigated by a reversed-phase high performance liquid chromatograph ic method with ultraviolet spectrometrical detection at 210 nm. A colu mn Lichrosphere RP-18, 5mum particle size, was used as stationary phas e, and mixture of methanol, acetonitrile and aqueous phosphate buffer as mobile phase, Improved retention times were achieved, and all the s ubstances were eluted in 12 minutes. Baseline separation for the three of them, and similar sensitivity of all the five penicillins are the characteristics of the chromatogram. The regression data for the quant itative determination of each penicillin are also given in this work.