Analyse de Médicaments à Potentiel Toxicomanogène par GC-MS : Mise au Point et Validation d’une Méthode

Abstract

Today the world knows a new form of addiction, which is the misuse of psychoactive substances (PAS) and the aim of this work is the development and validation of a chromatographic technique adapted to the qualitative and quantitative determination of PAS in biological matrices. The study is an experimental one conducted at the laboratory of Toxicology of the Department of Pharmacy SETIF from january to june 2022. The separation of the molecules was performed on a capillary column with a stationary phase 5% diphenyl/95% dimethyl polysiloxane. The chromatographic method was developed with an injection temperature of 250 °C and a transfer line temperature of 290 °C. The thermal program starts with an initial temperature of 65 °C for 1 min then increases by three levels with the following speeds : 40 °C/min up to 200 °C, 15 °C/min up to 250 °C and 20 °C/min up to 290 °C which is the maximal temperature. The total analysis time is 14.71 min. The technique used for the pretreatment of biological matrices is an alkaline liquid-liquid extraction at pH=10 with a 9V/1V chloroform/n-propanol solvent mixture. The optimization was done in SCAN mode in ordre to identify the different molecules and then in SIM mode with three fragments for each molecule for more sensitive results. This approach allowed us to obtain chromatographic peaks for four molecules : Tramadol, Clomipramine, Chlorpromazine and Levomepromazine with retention times of : 7.85, 10.36, 10.92 and 11.07 min respectively. The validation of this method was done according to the V3 protocol of the SFSTP 2003- 2006 giving the following results : a sensitive, specific and linear method with a good extraction yield. However, the results of correctness, precision and reliability tests were inconclusive.