A review of current bioanalytical approaches in sample pretreatment techniques for the determination of antidepressants in biological specimens

Antidepressants are a class of compounds widely used in clinical settings for the treatment of several diseases. In the last years there has been a considerable increase in their consumption, representing an important public health issue in several countries. Because they are substances with narrow therapeutic windows, and since they are capable of interacting with other classes of compounds, monitoring of these compounds is of relevance, minimizing the risk of medical interactions as well as side and toxic effects. In addition, understanding the extent of their use, their detection through routine toxicology tests and development of new methods for detection and monitoring is of extreme importance concerning public health, patient well-being, and implications in clinical and forensic situations. The main objective of this work is to perform a critical review on the biological samples used in the detection and quantification of antidepressants with special focus on the techniques for sample preparation.info:eu-repo/semantics/publishedVersio

Chromatographic approaches in forensic toxicological analysis

Conferência por convite no 13º Encontro Nacional de Cromatografia, que decorreu em Dezembro de 2023 em LisboaChromatography plays a fundamental role in forensic toxicology, serving as a powerful analytical tool for identifying and quantifying toxic substances in biological samples. Indeed, it is the science of separation, and it is used to isolate components from complex mixtures. Gas and liquid chromatography instruments coupled with mass spectrometry equip forensic laboratories nowadays, and enable accurately identifying and quantifying drugs and metabolites in several biological specimens, from the most common blood and urine to the unconventional oral fluid and hair samples. These techniques allow the efficient separation of the compounds of interest from endogenous interferences (e.g. proteins, lipids) and their detection. For most substances of toxicological interest, this detection is performed by mass spectrometry, as only this highly selective and sensitive technology is capable of unequivocally identifying the substances present in a sample, allowing obtaining forensically valid and sound results. In this talk, practical routine cases will be presented and discussed.info:eu-repo/semantics/draf

Current Technologies and Considerations for Drug Bioanalysis in Oral Fluid

Oral fluid analysis for drugs was first used almost 30 years ago for the purpose of therapeutic drug monitoring. Since then, oral fluid bioanalysis has become more popular, mainly in the fields of pharmacokinetics, workplace drug testing, criminal justice, driving under the influence testing programs, and therapeutic drug monitoring. In fact, oral fluid can provide a readily available and non-invasive medium, without any privacy loss by the examinee, which occurs for instance during the collection of urine samples. It is believed that drug concentrations in oral fluid may parallel those measured in blood. This feature makes oral fluid an alternative analytical specimen to blood, which assumes particular importance in roadside testing, the most published application of this sample. Great improvements in the development of accurate and reliable methods for sample collection, in situ detection devices (on-site drug detection kits), and highly sensitive and specific analytical methods for oral fluid testing of drugs have been observed in the last years. However, without mass spectrometry-based analytical methods, e.g. liquid chromatography coupled to mass spectrometry (LC/MS) or tandem mass spectrometry (LC/MS/MS), the desired sensitivity would not be met, due to the low amounts of sample usually available for analysis. This review will discuss a series of published papers on the applicability of oral fluid in the field of analytical, clinical and forensic toxicology, with special focus on its advantages and drawbacks over the normally used biological specimens and the main technological advances over the last decade, which made possible oral fluid bioanalysis for drugs

Analysis of Cannabinoids in Biological Specimens: An Update

Cannabinoids are still the most consumed drugs of abuse worldwide. Despite being considered less harmful to human health, particularly if compared with opiates or cocaine, cannabis consumption has important medico-legal and public health consequences. For this reason, the development and optimization of sensitive analytical methods that allow the determination of these compounds in different biological specimens is important, involving relevant efforts from laboratories. This paper will discuss cannabis consumption; toxicokinetics, the most detected compounds in biological samples; and characteristics of the latter. In addition, a comprehensive review of extraction methods and analytical tools available for cannabinoid detection in selected biological specimens will be reviewed. Important issues such as pitfalls and cut-off values will be considered.info:eu-repo/semantics/publishedVersio

When hair is the only biological specimen available: Analysis of a mummified scalp fragment

Comunicação Oral realizada, 27th Meeting of the Society of Hair Testing (SOHT), Lisboa (Portugal) 7-9 June 2023Hair testing provides useful and important information in forensic scenarios, as it complements data obtained from other biological specimens. Hair has been used for years to document exposure to drugs in a number of settings, for instance workplace drug testing, drug facilitated crimes and post-mortem toxicology. The authors present a case of decomposed human remains (unidentified) which appeared in a vacant house. A handmade pipe, a mouthpiece, cigarettes and syringes, indicating the consumption of drugs of abuse were found near the body. There was information that the deceased was addicted to drugs, but the specific substances were unknown. No pathological history and/or usual medication, were known, and the cause of death was ignored. The only biological sample available for toxicological analysis was mummified scalp with some hairs. The non-biological samples were analysed by GC-MS, and the following substances were detected: syringe A – cocaine, heroin, phenacetin, paracetamol; syringe B - cocaine, phenacetine, caffeine, nicotine, noscapine; mouthpiece – cocaine; handmade pipe - cocaine and metabolites, phenacetin and metabolites, paracetamol; cigarette A – nicotine and cotinine; cigarette B – nicotine, cotinine, phenacetin, caffeine. These results oriented hair testing to opiates and cocaine, which were analysed by GC-MS after appropriate extraction and clean- up. Hair was positive for cocaine (57 ng/mg), benzoylecgonine (17 ng/mg), norcocaine (2.20 ng/mg), cocaethylene (not quantitated), 6-acethylmorphine (4.65 ng/mg), morphine (4.52 ng/mg), codeine (0.83 ng/mg) and tramadol (0.87 ng/mg). The findings in hair are compatible with those in the paraphernalia; as such, it could be concluded that those objects belonged to the deceased. Hair analysis suggested that this death could be related to the consumption of heroin and cocaine.N/

Recent Approaches in the Determination of Biomarkers, Drugs of Abuse and Medicines

Funding: This work is supported by projects UIDB/00709/2020 and UIDP/00709/2020 (CICS-UBI); UIDB/04378/2020 and UIDP/04378/2020 (Applied Molecular Biosciences Unit UCIBIO), LA/P/0140/2020 (i4HB) carried out by National Funds by Foundation for Science and Technology (FCT) and co-financed by community funds.publishersversionpublishe

New Method for the Monitoring of Antidepressants in Oral Fluid Using Dried Spot Sampling

The increase in the consumption of antidepressants is a public health problem worldwide, as these are a class of compounds widely used in the treatment of several illnesses, such as depression and anxiety. This work aimed to develop and optimize a method for the quantification of a number of antidepressants and their metabolites (fluoxetine, venlafaxine, O-desmethylvenlafaxine, citalopram, sertraline, and paroxetine) in 100 μL of oral fluid using the dried saliva spots (DSS) sampling approach and gas chromatography coupled with tandem mass spectrometry (GC–MS/MS). The method was validated, presenting linearity within the studied range, with detection and quantification limits ranging between 10 and 100 ng/mL, and coefficients of determination (R2) of at least 0.99 for all analytes. Recoveries were between approximately 13 and 46%. The analysis of precision and accuracy presented acceptable coefficients of variation and relative errors, considering the criteria usually accepted in the validation of bioanalytical procedures. The method herein described is the first to be reported using DSS for the extraction of antidepressants, proving to be a sensitive, simple, and fast alternative to conventional techniques, and capable of being routinely applied in clinical and forensic toxicology scenariosinfo:eu-repo/semantics/publishedVersio

The potential of dried saliva spots for antidepressant drugs monitoring

Comunicação apresentada no 10º Congresso Iberoamericano de Ciências Farmacêuticas, Coimbra, Outubro de 2023. Abstract da comunicação publicado na Acta Farmacêutica Portuguesa. vol. de Outubro 2023. ISSN 2182-3340.Introduction: Portugal has one of the highest rates of mental illness in Europe, and the consumption of antidepressants amongst its population has doubled between the years 2013 and 2016. Approximately 30 million packs of medication are prescribed and dispensed annually in this country to treat major depressive disorders. Therapeutic Drug Monitoring (TDM) is a practice established for a small number of drugs, for which there is a direct relationship between concentration and pharmacological effect at the site of action. Commonly, TDM involves measuring drug concentrations in serum, plasma or blood, being complemented with clinical observation measures to assess patient’s condition, support the individualization of therapy, detect changes in the patient´s pathophysiological status or the modification of the drug pharmacokinetics, but also to assess adherence to therapy. Methodology: The present work describes a methodology with great potential for TDM purposes, allowing the determination of antidepressants (fluoxetine, venlafaxine, citalopram, sertraline, paroxetine and metabolites) using 100 μL of oral fluid with dried saliva spots (DSS) and analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). Results: For both sampling and extraction with DSS, several parameters were optimized using the statistical tool Design of Experiments (DoE), namely: drying and extraction times, extraction solvent and volume. The final optimized conditions were: 1 hour of drying, 1 mL of methanol and 5 minutes of extraction. The method was validated showing linearity within the adopted therapeutic ranges, with limits of detection and quantification between 10 and 100 ng/mL. All validation parameters were assayed according to the SWGTOX guidelines. Discussion: This is the first work that uses DSS to extract antidepressants from oral fluid samples, proving to be a sensitive, simple and fast alternative to conventional techniques and samples used in TDM (solid phase extraction based procedures and plasma samples). It also reveals potential to be routinely applied in TDM and forensic toxicology purposes, as it has been successfully applied to the analysis of authentic patient samples.N/

Quantification of antidepressants in oral fluid and plasma samples using microextraction by packed sorbent and analysis by gas chromatography-tandem mass spectrometry

The 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.info:eu-repo/semantics/publishedVersio