Simultaneous Determination of Methaqualone and Diazepam in Plasma by Derivative Spectroscopy

Abstract
A spectrophotometric method for the simultaneous determination of methaqualone and diazepam in plasma by second-derivative spectroscopy is reported. The proposed method is quite sensitive (it allows the determination of therapeutic levels of both pharmaceuticals) and easy to implement. It provided average recoveries of 93.75% and 99.04% for methaqualone and diazepam, respectively.