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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).
- Optimization and validation of an analytical method for the determination of opiates in urine using microextraction by packed sorbentPublication . Simão, Ana Y.; Monteiro, Catarina; Marques, Hernâni; Rosado, Tiago; Barroso, Mário; Andraus, Maristela; Gallardo, EugeniaAccording to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), approximately 1.3 million individuals have used opiates, both for medical and illicit purposes1, presenting a significant public health challenge2,3. To address this issue, methods for quantifying these substances are needed. Urine is a commonly employed matrix in clinical and forensic toxicological analyses due to its ease of collection and ample availability. Its short detection window is particularly effective for monitoring recent drug exposure4,5. This study aimed to optimize a method for determining tramadol, codeine, morphine, 6-acetylmorphine, 6- acetylcodeine, and fentanyl in urine samples (250 μL). The process involved centrifugation, acid hydrolysis, and extraction using microextraction by packed sorbent (MEPS). MEPS offered a rapid, environmentally friendly, and reusable extraction technique6. All parameters that influence the extraction were previously optimized. The method was validated following international guidelines, demonstrating excellent linearity [1 to 1000 ng/mL for all compounds, except for fentanyl (10 to 1000 ng/mL), with coefficients of determination of at least 0.99], and presenting coefficients of variation and bias ≤ 15% for precision and accuracy, except for the lowest calibrator (≤ 20%). Recoveries obtained ranged from 17 to 107%, with lowest percentages for morphine (12 to 17%). Despite the low extraction efficiency obtained for morphine, it was possible to detect concentrations as low as 1 ng/mL for all compounds, except for fentanyl (10 ng/mL). The method was successfully applied to real samples from consumers of these substances. This is the first method to use MEPS and GC-MS/MS for the simultaneous determination of these six opioids in urine samples.
- Otimização de um método para a determinação de anfetaminas e derivados em cabelo por microextração em seringa empacotadaPublication . Pires, Bruno; Simão, Ana Y.; Rosado, Tiago; Gallardo, Eugenia; Barroso, MárioTêm sido utilizados diferentes protocolos de extração para a determinação de compostos relacionados com anfetaminas em cabelo. A microextração em seringa empacotada (MEPS) é uma versão miniaturizada da extração em fase sólida que já tem sido aplicada para determinar diversas drogas em cabelo (por exemplo, opiáceos, cocaína, ketamina, etc.). No entanto, no que diz respeito às anfetaminas, a MEPS só foi ainda utilizada em cabelo para a determinação de anfetamina (AMP) e metanfetamina (MAMP). O objetivo deste trabalho foi o desenvolvimento e otimização de um método para determinar não só a AMP e a MAMP, como também MDA, MDMA, MDE e MBDB em amostras cabelo, utilizando a MEPS como técnica de extração. O cabelo pulverizado (50 mg) foi incubado com NaOH 1M a 45 ºC durante a noite, após o que se adicionou HCl 10M para neutralizar. De seguida, a solução foi centrifugada, recolhendo cuidadosamente o sobrenadante. Após se realizar a extração recorrendo ao MEPS, adicionou-se 30 μL de MBTFA ao eluato obtido, e as amostras foram evaporadas à secura. Posteriormente foram derivatizadas com recurso a microondas e utilizando 50 μL de MBTFA. O produto derivatizado foi então analisado por GC-MS em modo SIM. O procedimento de MEPS foi optimizado usando os softwares MiniTab e SPSS, mediante dois testes de Desenho Experimental (DOE) e uma análise não paramétrica, respetivamente. Inicialmente, foi conduzido um DOE fatorial, com o estudo dos seguintes parâmetros: número de aspirações de amostra (entre 5 e 15 aspirações de 100 μL); número de aspirações para a lavagem [entre 1 e 3 aspirações com 50 μL de H2O ultrafiltrada e 50 μL de H2O:MeOH (95:5)]; e número de aspirações para a eluição (entre 2 e 6 eluições com 100 μL de 2% NH4OH em ACN). Foi necessário implementar um Desenho Experimental de Superfície de Resposta (SR), estendendo os limites dos parâmetros mencionados para uma análise mais detalhada. Os intervalos ampliados foram os seguintes: 0 a 26,1 aspirações de 100 μL de amostra; 0 a 7,7 aspirações de lavagem; e 0 a 10,3 aspirações de eluição. Após esta optimização, o método final de MEPS foi o seguinte: 18 aspirações de 100 μL de amostra; 0 aspirações para a lavagem; 7 aspirações com 100 μL de 2% NH4OH em ACN para a eluição. Este método permite a análise sensível de compostos derivados das anfetaminas em amostras de cabelo, podendo ser utilizado em situações onde estejam envolvidos.
- 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.
- 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.
- Microextraction action by packed sorbent in forensic drug analysisPublication . Rosado, Tiago; Pelixo, Rodrigo; Pires, Bruno; Catarro, João Miguel; Rosendo, Luana M.; Brinca, Ana T.; Antunes, Mónica; Soares, Sofia; Simão, Ana Y.; Barroso, Mário; Gallardo, EugeniaMicroextraction by packed sorbent (MEPS) efficiently combines extraction, pre-concentration, and cleanup in a single device comprising two parts: the MEPS syringe and the packed sorbent bed1. MEPS has been used for several bioanalytical applications, including extraction of endogenous metabolites, biomarkers, and drugs from biological samples. It is particularly useful in metabolomics and pharmacokinetic studies2,3. Regarding MEPS applicability to forensic toxicology, urine is the most used specimen, followed by oral fluid (despite of its relatively high viscosity). Protein precipitation followed by centrifugation and with, or without dilution of the supernatant is the most commonly reported approach. The most detected compounds in forensic settings using MEPS are drugs of abuse [opiates and opioids (26%), cocaine (13%) cathinones (11%), dissociative hallucinogens (11%), cannabinoids and amphetamines (9% each) and other drugs (10%)] and medicinal drugs [antidepressants (9%), benzodiazepines/Z drugs (4%)]. MEPS was also applied to a beverage for forensic purposes e.g. to evaluate its composition in drug-facilitated crimes. An important feature in MEPS is the miniaturization of the sorbent. A careful selection of the sorbent will allow working with complex matrices, separating the target analytes from interferences and improve recoveries. The most widely selected sorbent was the silica based C18 that is a popular reversed-phase material (41%). Starting in the 2000s, new modifications of sorbents appeared. Overall, what the future holds for MEPS applications in forensic toxicology is promising, and ongoing research and technological advancements are likely to enhance the capabilities of MEPS approaches, making this technique an increasingly valuable tool for toxicological investigations.
- Otimização de uma metodologia por microextração em seringa empacotada e cromatografia gasosa-espetrometria de massa em tandem para a identificação de arilciclohexaminas em amostras de cabeloPublication . Oliveira, Patrik; Simão, Ana Y.; Rosendo, Luana M.; Pedro, Soraia; Rosado, Tiago; Andraus, Maristela; Barroso, Mário; Gallardo, EugeniaAs novas substâncias psicoativas (NPS) têm vindo a tornar-se um problema cada vez mais um problema de saúde pública. Em Portugal, a ketamina (KET) entrou para a lista de NSP com o Decreto-Lei nº 54/2013. Inicialmente sintetizada com o intuito de substituir a fenciclidina (PCP) como anestésico, acabou por ser usada recreativamente devido aos seus efeitos alucinogénios e estimulantes. Recentemente, a esketamina (análogo da KET) foi introduzida com finalidade terapêutica no tratamento de depressão major refractária a outra terapêutica. Para distinguir o consumo terapêutico do recreativo é necessário que existam métodos que para a sua deteção e quantificação. Neste trabalho foi desenvolvido e otimizado um método para a deteção de KET e seu metabolito (norketamina – NK) em amostras de cabelo com recurso à microextração em seringa empacotada (MEPS) e cromatografia de gases acoplada à espetrometria de massa em tandem (GC-MS/MS). (1) Foi desenvolvido um método analítico para a determinação de KET e NK em amostras de cabelo com recurso à MEPS; (2) A GC-MS/MS foi crucial para deteção inequívoca dos analitos, aumentando a sensibilidade e seletividade do método; (3) As recuperações obtidas são adequadas e foram alcançados LODs baixos (alcançando os cut-offs (0,2 ng/mg) propostos pela Society of Hair Testing) (4) Primeiro método analítico que permite a determinação de KET e NK em amostras de cabelo com recurso a MEPS e GC-MS/MS