Development of the methods of strong medicines determination in human biological liquids for application in forensic and clinical toxicology is one of actual problems of pharmaceutical science, but validation of the analytical methods becomes much more vital and widely discussed problem in analytical toxicology in the last decade.
The purpose of the paper was to develop the methods of phenytoin quantitative determination in urine based on the offered before procedure of the analyte determination by the method of gas–liquid chromatography and to carry out validation of the developed methods in the variant of the method of calibration curve according to the approaches offered by authors for choosing the optimal procedure of phenytoin isolation from the mentioned biological matrix.
The set of GLC-methods of phenytoin quantitative determination in urine using different procedures of sample preparation – by extraction with chloroform in the acid medium and by maceration with acetonitrile without acidifying and at pH = 2 with subsequent separation of organic layer under the conditions of aqueous phase saturation by ammonium sulphate – has been developed.
Validation of the developed methods has been carried out and it has been set that acetonitrile application in the acid medium (рН = 2) is optimal for phenytoin determination in urine – extraction efficiency is maximal and equal to ~97%, and performance of linearity, accuracy and precision is optimal.
Application possibility of the offered approaches to validation of quantitative determination methods for forensic and toxicological analysis in the variant of the method of calibration curve for validation of procedure using the method of gas–liquid chromatography has been shown.
Development and validation of the methods of phenytoin determination in urine by the method of gas–liquid chromatography
