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- Determination of Ketamine and Norketamine in hair samples using MEPS as sample clean-upPublication . Simão, Ana Y.; Oliveira, Patrik; Rosendo, Luana M.; Rosado, Tiago; Gallardo, Eugenia; Andraus, Maristela; Barroso, MárioIntroduction and Aim: The use of hair samples to determine ketamine (K) and its metabolite, norketamine (NK), has been studied by several authors, using different clean-up approaches. However, microextraction by packed sorbent (MEPS), a miniaturized form of the classic solid-phase extraction has not been applied to date for the purpose. Therefore, a method to determine K and NK in hair samples was developed, optimized, and validated using MEPS as sample clean-up. Materials & Methods: Hair samples were scissor-cut into small fragments, and rinsed with methanol to remove dirt and externally deposited material. Following an overnight incubation with methanol at 65 ºC (no stirring), the compounds were analysed by GC-MS/MS without the need of derivatization procedures; MEPS conditions were: conditioning (5 x 250 µL of methanol and 4 x 250 µL of deionized water); load (10 x 150 µL of hair extract); washing (50 µL of 0.1% acetic acid and 50 µL of 10% methanol); and elution (100 µL of 3% ammonium hydroxide in methanol). Results & Discussion: The procedure resulted in acceptable recoveries, 39-61% for K and 32-43% for NK, and allowed reaching limits of quantification (LOQs) of 50 pg/mg for both analytes. The analytical method presented acceptable accuracy and precision with coefficients of variation typically lower than 15% and BIAS within ± 15%, except at the LOQ (20%). The method was successfully applied to 2 authentic samples, and ketamine concentrations were below 0.05 and 0.18 ng/mg. Norketamine was not detected. Conclusions: This work is the first analytical method using MEPS coupled to GC-MS/MS for the determination of K and NK in hair samples. Following a comparison with a SPE-based method using authentic samples, it was considered rapid and suitable for routine analysis. Acknowledgments: FCT (UIDB /00709/2020 and UIDP/00709/2020). A.Y. Simão acknowledges the PhD fellowship from FCT (2020.09070.BD).
- Determination of amphetamine-type psychostimulants in hair samples using MEPS as sample clean-up and gas-chromatography coupled with mass spectrometryPublication . Pires, Bruno; Simão, Ana Y.; Rosado, Tiago; Gallardo, Eugenia; Barroso, MárioNumerous protocols for the analysis of amphetamine-type psychostimulants (ATS) in hair have been employed over the years. Microextraction by packed sorbent (MEPS), a downsized version of solid-phase extraction (SPE), has been effectively applied in hair drug analysis, including substances like opiates, cocaine, and ketamine. However, concerning ATS, MEPS has primarily been used to the determination of amphetamine (AMP) and methamphetamine (MAMP) in hair1-4. The main objective of this study was to develop and validate a method using MEPS as a sample clean-up, for the determination of AMP, MAMP, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), 1-(1,3-benzodioxol-5-yl)propan-2-yl(ethyl)amine (MDE), and N-methyl-1-(1,3-benzodioxol-5-yl)-2-aminobutane (MBDB) in hair. The extraction procedure involved incubating 50 mg of hair with 1M NaOH at 45 ºC overnight, followed by neutralization with 10M HCl and centrifugation5. A Design of Experiments (DoE) approach was employed to optimize MEPS clean-up process, encompassing conditioning, loading, and elution steps. The eluted extract underwent derivatization and was analysed using gas chromatography coupled to mass spectrometry (GC-MS). The developed MEPS method yielded recoveries ranging from 8 to 52% for the different analytes in hair samples and linearity was obtained between 0.2 (cut-off proposed by SoHT) and 5.0 ng/mg. The precision and accuracy were in accordance to international method validation standards. This study introduces the first analytical method integrating MEPS with GC-MS for the detection of these specific amphetamines in hair samples. Notably, this method offers a viable alternative to conventional procedures, characterized by its speed, eco-friendliness, and cost-effectiveness.
- Determination of amphetamine-related drugs in hair using MEPS as sample clean-upPublication . Pires, Bruno; Simão, Ana Y.; Rosado, Tiago; Gallardo, Eugenia; Barroso, MárioIntroduction and aims: Different extraction and clean-up protocols have been used for amphetamine-related compounds determination in hair. Microextraction by packed sorbent (MEPS) is a miniaturized version of solidphase extraction (SPE) which has been applied to determine a number of drugs in hair (e.g., opiates, cocaine, ketamine, etc.) [1-4]. However, concerning amphetamine-related drugs, MEPS has only been used in hair for the determination of amphetamine (AMP) and methamphetamine (MAMP). The aim of this work was the development and validation of a method to determine AMP, MAMP, MDA, MDMA, MDE and MBDB in hair using MEPS for sample clean-up. Materials and methods: Hair (50 mg) was incubated with NaOH 1M at 45 °C overnight [5], after which HCl 10M was added for neutralization and the solution was centrifuged. The MEPS procedure for extract clean-up was optimized using the Design of Experiments (DoE) approach, and the final steps were: conditioning (1 x 250 μL of methanol and 1 x 250 μL of deionized water); loading (18 x 100 μL); and elution (7 x 100 μL of 2% NH4OH in acetonitrile). To the eluted extract, 30 μL of MBTFA was added (to avoid loss of analytes), and extracts were evaporated to dryness, following microwave-assisted derivatization with 50 μL of MBTFA. A gas chromatography coupled to mass spectrometry (GC-MS) system was used for determination. Results and discussion: The MEPS procedure resulted in recoveries of 8-14% for AMP, 14-20% for MAMP, 10-15% for MDA, 18-28% for MDMA, 25-43% for MDE and 34-52% for MBDB, in the linear range of 0.2-5.0 ng/mg. Precision and accuracy of the developed method were in accordance with the statements of international guidelines for method validation. Conclusions: This is the first analytical method using MEPS coupled to GC-MS to determine the selected amphetamines in hair samples, proving to be a great alternative to the classic procedures, being rapid, eco-friendly and less expensive.
- Sensors in the Detection of Abused Substances in Forensic Contexts: A Comprehensive ReviewPublication . Rosendo, Luana M.; Antunes, Mónica; Simão, Ana Y.; Brinca, Ana Teresa; Catarro, Gonçalo; Pelixo, Rodrigo; Martinho, João; Pires, Bruno; Soares, Sofia; Cascalheira, José Francisco; Passarinha, Luís; Rosado, Tiago; Barroso, Mário; Gallardo, Eugeniaorensic toxicology plays a pivotal role in elucidating the presence of drugs of abuse in both biological and solid samples, thereby aiding criminal investigations and public health initiatives. This review article explores the significance of sensor technologies in this field, focusing on diverse applications and their impact on the determination of drug abuse markers. This manuscript intends to review the transformative role of portable sensor technologies in detecting drugs of abuse in various samples. They offer precise, efficient, and real-time detection capabilities in both biological samples and solid substances. These sensors have become indispensable tools, with particular applications in various scenarios, including traffic stops, crime scenes, and workplace drug testing. The integration of portable sensor technologies in forensic toxicology is a remarkable advancement in the field. It has not only improved the speed and accuracy of drug abuse detection but has also extended the reach of forensic toxicology, making it more accessible and versatile. These advancements continue to shape forensic toxicology, ensuring swift, precise, and reliable results in criminal investigations and public health endeavours.
- Microextraction by Packed Sorbent as a Clean-up Approach for the Determination of Ketamine and Norketamine in Hair by Gas Chromatography--Tandem Mass SpectrometryPublication . Simão, Ana Y.; Oliveira, Patrik; Rosendo, Luana; Rosado, Tiago; Andraus, Maristela; Barroso, Mário; Gallardo, EugeniaThe use of new psychoactive substances has been increasing and constitutes a social and public health problem, and hence, toxicological analysis has become of utmost importance for the detection of such substances. In this article, we present the development and full validation of a simple, user and environmentally friendly, cheap and suitable method for the determination of ketamine and its main metabolite norketamine in hair samples. The procedure included using a miniaturized procedure-microextraction by packed sorbent with mixed-mode sorbent-for sample clean-up. Organic solvents use was minimal, and it was possible to obtain a linear method (0.05-10 ng/mg for both analytes). The extraction efficiency ranged from 32 to 61%, which did not impair sensitivity. The method proved to be selective, precise, accurate and suitable for routine analysis for the determination of said compounds in 50-mg hair samples.
- Determination of Antiepileptics in Biological Samples—A ReviewPublication . Martinho, João; Simão, Ana Y.; Barroso, Mário; Gallardo, Eugenia; Rosado, TiagoEpilepsy remains a disease that affects many people around the world. With the development of new drugs to treat this condition, the importance of therapeutic drug monitoring continues to rise and remains a challenge for the medical community. This review article explores recent advances in the detection of antiepileptic drugs across various sample types commonly used for drug monitoring, with a focus on their applications and impact. Some of these new methods have proven to be simpler, greener, and faster, making them easier to apply in the context of therapeutic drug monitoring. Additionally, besides the classic use of blood and its derivatives, there has been significant research into the application of alternative matrices due to their ease of sample collection and capacity to reflect drug behavior in blood. These advances have contributed to increasing the efficacy of therapeutic drug monitoring while enhancing its accessibility to the population.