Loading...
7 results
Search Results
Now showing 1 - 7 of 7
- Stability of Cocaine, Opiates, and Metabolites in Dried Saliva SpotsPublication . Almeida, Ema; Soares, Sofia; Gonçalves, Joana; Rosado, Tiago; Fernández, Nicolás; Rodilla, Jesus M.; Passarinha, Luís A.; Barroso, Mário; Gallardo, EugeniaDrug abuse still represents a global problem, and it is associated with an increased risk of diseases, injuries, and deaths. Cocaine (COC) and opiates are the most abused drugs and account for a significant number of fatalities. Therefore, it is important to develop methods capable of effectively identifying and quantifying these substances. The present study aims to evaluate the long- term stability of COC, ecgonine methylester (EME), benzoylecgonine (BEG), cocaethylene (COET), norcocaine (NCOC), morphine (MOR), codeine (COD) and 6-monoacetylmorphine (6-MAM) in oral fluid samples. The analytes of interest were isolated from the matrix (50 μL) using the dried saliva spots (DSS) sampling approach and were subsequently analyzed by gas chromatography coupled with tandem mass spectrometry (GC–MS/MS). The parameters that could influence the stability of the target compounds were studied, and these were storage temperature, light, use of preservatives (and respective concentrations), and time. The effects of each parameter were evaluated using the design of experiments (DOE) approach. The stability of the target analytes was improved when the DSS were stored at room temperature, in the presence of light and using 1% sodium fluoride. The best conditions were then adopted for the DSS storage and long-term stability was assessed. COD was only stable for 1 day, EME was stable for 3 days, COC, COET, NCOC and 6-MAM were stable for 7 days, MOR for 14 days and BEG remained stable throughout the study (136 days). This is the first study that evaluates the stability of these compounds in oral fluid samples after application in DSS cards, and optimizes the conditions in order to improve their stability
- The potential of oral fluid in drug monitoring: an updatePublication . Gallardo, Eugenia; Rosado, Tiago; Barroso, Mário
- 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.
- Evaluation of Antipsychotic Drugs’ Stability in Oral Fluid SamplesPublication . Gameiro, Carina; Gonçalves, Joana; Soares, Sofia; Rosado, Tiago; Araujo, André R. T. S.; Passarinha, Luís A.; Barroso, Mário; Gallardo, EugeniaAntipsychotics have narrow therapeutic windows, and their monitoring in biological fluids is therefore important; consequently, stability in those fluids must be investigated during method development and validation. This work evaluates the stability of chlorpromazine, levomepromazine, cyamemazine, clozapine, haloperidol, and quetiapine in oral fluid (OF) samples, using the dried saliva spots (DSS) sampling approach and gas chromatography coupled to tandem mass spectrometry. Since many parameters can influence the stability of the target analytes, design of experiments was adopted to check the crucial factors that affect that stability in a multivariate fashion. The studied parameters were the presence of preservatives at different concentrations, temperature, light, and time. It was possible to observe that antipsychotic stability improved when OF samples in DSS were stored at 4 °C, with a low ascorbic acid concentration, and in the absence of light. With these conditions, chlorpromazine and quetiapine were stable for 14 days, clozapine and haloperidol were stable for 28 days, levomepromazine remained stable for 44 days, and cyamemazine was stable for the entire monitored period (146 days). This is the first study that evaluates the stability of these antipsychotics in OF samples after application to DSS cards.
- Quantification of antidepressants in oral fluid and plasma samples using microextraction by packed sorbent and analysis by gas chromatography-tandem mass spectrometryPublication . Soares, Sofia; Rosado, Tiago; Barroso, Mário; Gallardo, EugeniaThe consumption of antidepressants is extremely significant as they are a class of medications widely used in the treatment of numerous disorders and are therefore considered a public health problem throughout the world. The aim of this work was to develop and optimize two methodologies for the determination of selected antidepressants and metabolites (fluoxetine, venlafaxine, O-desmethylvenlafaxine, citalopram, sertraline, paroxetine), in 250 µL of sample (oral fluid and plasma) using microextraction by packed sorbent (MEPS) as the extraction technique and gas chromatography coupled to tandem mass spectrometry (GC–MS/MS) for analysis. The two methods were fully validated considering the internationally accepted criteria for bioanalytical procedures, presenting linearity within the studied range, with limits of quantification between 10 and 100 ng/mL, coefficients of determination (R2) of at least 0.99 and precision and accuracy with acceptable values of coefficients of variation and relative errors for all antidepressants in study and for both specimens. Recoveries ranged between approximately 12 and 93 % for oral fluid samples and between approximately 28 and 101 % for plasma samples. To our best knowledge, the described methods are the first to be reported using MEPS and GC–MS/MS for the identification of antidepressants in oral fluid and plasma samples, proving to be sensitive, simple, fast and capable of being applied in routine clinical and forensic toxicology scenarios.
- Development and optimization of a new method to determine antidepressants in oral fluid by microextraction by packed sorbent and analysis by GC-MS/MSPublication . Soares, Sofia; Rosado, Tiago; Barroso, Mário; Gallardo, EugeniaBetween 2013 and 2016, the consumption of antidepressants doubled in Portugal, with around 30 million packages of medication for depression, anxiety and other mental health problems dispensed annually. This phenomenon has even given rise to several alerts, which was highlighted in the 2017 report of the National Program for Mental Health, as Portugal has one of the highest rates of mental illness in Europe1. Therapeutic drug monitoring is well established for a small number of drugs, namely for those where a direct relationship between concentration and pharmacological effect at the site of action exists, which in turn is predictably reflected in the response. Drug concentrations in the various biological fluids are used in conjunction with other clinical observation measures to assess the patient's condition, and further support the individualization of therapy. Within this group of drugs targeted for monitoring are antidepressants. In recent years, oral fluid has gained more and more importance in the field of therapeutic drug monitoring, as a non-invasive and painless alternative to traditionally sampled specimens (e.g. blood, plasma). MEPS is a miniaturized solid-phase extraction (SPE) and therefore has a great advantage in the reduced operating volumes and consequently lower amounts of sample and organic solvents are required. As a result, MEPS decreases the time required for extraction, clean-up and concentration of analytes. This is the first work that uses MEPS as sample preparation technique for the determination of antidepressants and metabolites in oral fluid samples (250 µL). The simple extraction procedure proved to be efficient, requiring only 250 µL of biological sample, making it an excellent alternative for the determination of these compounds in routine clinical and forensic toxicology laboratories and for therapeutic monitoring purposes.
- Optimization and validation of a procedure using the dried saliva spots approach for the determination of tobacco markers in oral fluidPublication . Marques, Hernâni; Rosado, Tiago; Barroso, Mário; Passarinha, Luis; Gallardo, EugeniaExposure to tobacco smoke is one of the most common causes of premature death worldwide and is the cause of 8 million deaths annually. We have developed, optimized, and validated a procedure for the detection of nicotine, cotinine and trans-3-hydroxycotinine (biomarkers of tobacco exposure) in oral fluid using the dried saliva spots sampling approach and gas chromatography coupled to tandem mass spectrometry, thus allowing the distinction between active and passive smokers. For optimization, four parameters were evaluated, namely extraction solvent, extraction solvent volume, extraction time and spots drying time. During method validation, the parameters selectivity, linearity, precision and accuracy, recovery, stability, and dilution factor were assessed. Linearity was obtained for all target analytes in the concentration range of 10–200 ng/mL allowing the quantification of compounds up to 1000 ng/mL considering the dilution factor. The method recoveries ranged from 29.2% to 43.30% for nicotine, 66.60–89.10% for cotinine and 80.30–92.80% for trans-3-hydroxycotinine, while achieving intra-day, inter-day and intermediate precision and accuracy values never higher than 10.37% and ±6.62% respectively for all compounds. The herein described analytical method is the first to allow the determination of tobacco biomarkers in oral fluid using dried saliva spots, which is considered a sensitive, simple and low-cost alternative to conventional methods.