Loading...
3 results
Search Results
Now showing 1 - 3 of 3
- Antidepressants detection and quantification in whole blood samples by GC–MS/MS, for forensic purposesPublication . Truta, Liliana; Castro, André Lobo; Tarelho, Sónia; Costa, Pedro; Sales, M. Goreti F.; Teixeira, Helena M.Depression is among the most prevalent psychiatric disorders of our society, leading to an increase in antidepressant drug consumption that needs to be accurately determined in whole blood samples in Forensic Toxicology Laboratories. For this purpose, this work presents a new gas chromatography tandem mass spectrometry (GC–MS/MS) method targeting the simultaneous and rapid determination of 14 common Antidepressants in whole blood: 13 Antidepressants (amitriptyline, citalopram, clomipramine, dothiepin, fluoxetine, imipramine, mianserin, mirtazapine, nortryptiline, paroxetine, sertraline, trimipramine and venlafaxine) and 1 Metabolite (N-desmethylclomipramine). Solid-phase extraction was used prior to chromatographic separation. Chromatographic and MS/MS parameters were selected to improve sensitivity, peak resolution and unequivocal identification of the eluted analyte. The detection was performed on a triple quadrupole tandem MS in selected ion monitoring (SIM) mode in tandem, using electronic impact ionization. Clomipramine-D3 and trimipramine-D3 were used as deutered internal standards. The validation parameters included linearity, limits of detection, lower limit of quantification, selectivity/ specificity, extraction efficiency, carry-over, precision and robustness, and followed internationally accepted guidelines. Limits of quantification and detection were lower than therapeutic and subtherapeutic concentration ranges. Overall, the method offered good selectivity, robustness and quick response (<16 min) for typical concentration ranges, both for therapeutic and lethal levels.
- A fast and reliable method for GHB quantitation in whole blood by GC–MS/MS (TQD) for forensic purposesPublication . Castro, André Lobo; Tarelho, Sónia; Dias, Mário; Reis, Flávio; Teixeira, Helena M.Gamma-Hydroxybutyric Acid (GHB) is an endogenous compound with a story of clinical use since the 1960’s. However, due to its secondary effects, it has become a controlled substance, entering the illicit market. A fully validated, sensitive and reproducible method for the quantification of GHB by methanolic precipitation and GC-MS/MS (TQD) in whole blood is presented. Using 100 µL of whole blood, obtained results included a LOD and LLOQ of 0.1 mg/L and a recovery of 86% in a working range between 0.1 and 100 mg/L. This method is sensitive and specific to detect the presence of GHB in small amounts of whole blood (both ante-mortem or post-mortem), and is, to the authors’ knowledge, the first GC-MS-MS TQD method that uses different precursor ions and product ions for the identification of GHB and GHB-D6 (internal standard). Hence, this method may be especially useful for the study of endogenous values in this biological sample.
- Gamma-hydroxybutyric acid endogenous production and post-mortem behaviour – The importance of different biological matrices, cut-off reference values, sample collection and storage conditionsPublication . Castro, André Lobo; Dias, Mário; Reis, Flávio; Teixeira, Helena M.Gamma-Hydroxybutyric Acid (GHB) is an endogenous compound with a story of clinical use, since the 1960's. However, due to its secondary effects, it has become a controlled substance, entering the illicit market for recreational and “dance club scene” use, muscle enhancement purposes and drug-facilitated sexual assaults. Its endogenous context can bring some difficulties when interpreting, in a forensic context, the analytical values achieved in biological samples. This manuscript reviewed several crucial aspects related to GHB forensic toxicology evaluation, such as its post-mortem behaviour in biological samples; endogenous production values, whether in in vivo and in post-mortem samples; sampling and storage conditions (including stability tests); and cut-off reference values evaluation for different biological samples, such as whole blood, plasma, serum, urine, saliva, bile, vitreous humour and hair. This revision highlights the need of specific sampling care, storage conditions, and cut-off reference values interpretation in different biological samples, essential for proper practical application in forensic toxicology.