Determination of chloramphenicol and thiamphenicol in the presence of their degradation products using first derivative spectrophotometry

A method is presented for the determination of chloramphenicol and thiamphenicol in the presence of their degradation products using first derivative spectrophotometry by measuring the absolute value of the first derivative curves at the zero contribution of the corresponding degradation products, the concentration of the intact drug can be calculated directly without interference of the degradation product. The method was proved using laboratory prepared mixtures of the intact drugs with their degradation products

pH-Induced difference spectrophotometric assay of amoxicillin in the presence of dicloxacillin or flucloxacillin

A method is presented for the direct determination of amoxacillin in the presence of dicloxacillin or flucloxacillin without prior separation using first and second derivative spectra [AD 1 and AD 2] at the zero contribution of flucloxacillin or dicloxacillin. The method was proved using laboratory prepared mixtures of amoxacillin with flucloxacillin or dicloxacillin