Implementación de un metodo analitico cualitativo para la identificación de sustancias controladas de origen sintetico por la tecnica de CG-MS en el grupo de química de la Fiscalía General De La Nación Seccional Norte De Santander.

Abstract

Controlled substances are one of the most common types of evidence analyzed in forensic laboratories, the high levels of cases involving illicit drugs in recent years have created the need to develop rapid detection techniques to reduce the backlog of cases and expedite investigations. confirmatory analysis. The most widely used technique for the analysis of seized illicit drugs is gas chromatography with a mass selective detector (GC-MS). In this work, a qualitative analytical method was implemented by GC-MS to determine samples of seized illicit drugs (amphetamine, methamphetamine, 2C-B, ketamine and clonazepam) that arrive at the Chemistry Laboratory of the Attorney General's Office of the Cúcuta - North section of Santander, this method was implemented by evaluating the parameters of selectivity, decision limit (CCα), detection capacity (CCβ), identification limit and robustness, obtaining as a result that: The retention time of 2C-B is affected by each one of the chromatographic variables modified in the evaluation of the robustness and symmetry of the ketamine peak is not affected by any of these variables, the other three analytes (amphetamine, ketamine and clonazepam) are affected by at least one of the variables. However, these results do not hinder the correct identification of the five analytes, obtaining that none of the modified variables for the evaluation of robustness significantly affects the analytical method, with these results it is guaranteed that the conditions of the analyte method are adequate. to obtain correct subtractions. Next, the selectivity of the method was determined, for this the resolution and tail factor were determined, obtaining that: the resolution of the analytes is higher than the established acceptance criterion (1.6) and the results of the tail factor of the analytes of interest They are within the acceptance range As = 0.9 -2.0. Finally, the CCα (non-compliance decision) and CCβ (non-compliance decision) and detection limit were determined for each analyte of interest, obtaining that amphetamine has a CCα: 153.1 mg/L, CCβ: 275.0 mg /l and detection limit: 300 mg/l; methamphetamine has a CCα: 154.2 mg/l, CCβ: 287.5 mg/l and detection limit: 300 mg/l; 2C-B has a CCα 305.0 mg/l, CCβ 398.0 mg/l and detection limit 500 mg/l; Ketamine has a CCα 51.3 mg/L, CCβ 73.8 mg/L and detection limit 112 mg/L and clonazepam has a CCα 81.0 mg/L, CCβ 99.0 mg/L and detection limit 200 mg/L. Finally, the “SINTETICAS” analytical method was applied before and after the evaluation of the method in 29 packages seized during the months of October 2023 and January 2024, these packages had already been previously identified by the chemistry laboratory. Obtaining that the results of the 29 packages analyzed with the evaluated method coincide in their entirety with the laboratory results obtained before the evaluation of the method, thus confirming that the analytical method implemented in the chemistry laboratory of the Attorney General's Office Cúcuta – Norte de Santander sectional nation does not present false positives or false negatives. The results obtained in this work show the usefulness of this method to perform exact and precise qualitative analyzes for the detection of 5 illicit drugs.