Analysis of hospital-formulated oral liquid preparations by second derivative ultraviolet spectroscopy

Second derivative ultraviolet spectrophotometric methods have been devised for the analysis of hospital-formulated oral liquid preparations. These rapid techniques are useful in the routine quality control of oral liquid formulations where direct spectrophotometric determination of the drug analyte is precluded by interference from formulation excipients and colouring agents. This report describes examples in which the active principles of a dipipanone mixture, a methadone mixture and an orphenadrine syrup were determined by derivative spectroscopy. In each case spectral interference from formulation excipients was abolished. The accuracy, precision and specificity of each method has been established.