Alternative matrices in forensic toxicology: a critical review

Point-of-care testing of methamphetamine and cocaine utilizing wearable sensors

The imperative for the point-of-care testing of methamphetamine and cocaine in drug abuse prevention necessitates innovative solutions. To address this need, we have introduced a multi-channel wearable sensor harnessing CRISPR/Cas12a system. A CRISPR/Cas12a based system, integrated with aptamers specific to methamphetamine and cocaine, has been engineered. These aptamers function as signal-mediated intermediaries, converting methamphetamine and cocaine into nucleic acid signals, subsequently generating single-stranded DNA to activate the Cas12 protein. Additionally, we have integrated a microfluidic system and magnetic separation technology into the CRISPR system, enabling rapid and precise detection of cocaine and methamphetamine. The proposed sensing platform demonstrated exceptional sensitivity, achieving a detection limit as low as 0.1 ng/mL. This sensor is expected to be used for on-site drug detection in the future.

NPS-EQA PART I: Four years' experience in external quality assessment program in Italy for classical and new psychoactive substances analysis in oral fluid

In 2019, Italian National Institute of Health established an external quality assessment program (EQA) to evaluate the performance of oral fluid testing for classical and new psychoactive substances by laboratories participating in the National Early Warning System collaborative centres. This report presents the results of four rounds between 2019 and 2023. Eleven oral fluid specimens, including 3 blank samples, were prepared by adding different classes of and new psychoactive drugs at known concentrations to pre-screened drug-free oral fluid. False-negative and false-positive results were calculated for the qualitative data evaluation. The quantitative evaluation measured the imprecision and accuracy of the results, in terms of coefficient of variation (CV%) and percent error (ERR%), respectively, with respect to a mean value obtained by reference laboratories. Z-score values were then calculated. Over the years, there has been a significant improvement in false-negative results (from 42.7% in the first year to 19.4% in the last year), but not in false-positive results (from 33.3% in the first year to 22.2% in the last one). In addition to the classic drugs of abuse (e.g. cocaine, amphetamine, methadone), the substances found in false positive samples belonged to the class of synthetic cannabinoids (e.g 5-fluoro CUMYL-PINACA and 5-fluoro-EDMB-PICA), synthetic opioids (e.g butyrylfentanyl) and tryptamines (e.g. 5-methoxy-N-methyl-N-isopropyltryptamine). The four rounds yielded a mean ERR% of approximately 22.1% and a mean CV% of around 41.5%. The participating laboratories demonstrated variable performances in relation to the class of analysed psychoactive substances, as evidenced by the calculated Z-scores. Between 25% and 60% of the reported results in all rounds should be considered satisfactory. EQA is a crucial element of laboratory quality management systems. It promotes continuous improvement and maintains high standards in the field of forensic and clinical drug testing.

Metal-DNA interactions: Exploring the impact of metal ions on key stages of forensic DNA analysis

Forensic DNA analysis continues to be hampered by the complex interactions between metals and DNA. Metal ions may cause direct DNA damage, inhibit DNA extraction and polymerase chain reaction (PCR) amplification or both. This study evaluated the impact of metal ions on DNA extraction, quantitation, and short tandem repeat profiling using cell-free and cellular (saliva) DNA. Of the 11 metals assessed, brass exhibited the strongest PCR inhibitory effects, for both custom and Quantifiler Trio quantitation assays. Metal ion inhibition varied across the two quantitative PCR assays and the amount of DNA template used. The Quantifiler Trio internal PCR control (IPC) only revealed evidence of PCR inhibition at higher metal ion concentrations, limiting the applicability of IPC as an indicator of the presence of metal inhibitor in a sample. Notably, ferrous ions were found to significantly decrease the extraction efficiency of the DNA-IQ DNA extraction system. The amount of DNA degradation and inhibition in saliva samples caused by metal ions increased with a dilution of the sample, suggesting that the saliva matrix provides protection from metal ion effects.

First Insight into Fetal Exposure to Legacy and Emerging Plasticizers Revealed by Infant Hair and Meconium: Occurrence, Biotransformation, and Accumulation

Epidemiological studies have demonstrated the embryonic and developmental toxicity of plasticizers. Thus, understanding the in utero biotransformation and accumulation of plasticizers is essential to assessing their fate and potential toxicity in early life. In the present study, 311 infant hair samples and 271 paired meconium samples were collected at birth in Guangzhou, China, to characterize fetal exposure to legacy and emerging plasticizers and their metabolites. Results showed that most of the target plasticizers were detected in infant hair, with medians of 9.30, 27.6, and 0.145 ng/g for phthalate esters (PAEs), organic phosphate ester (OPEs), and alternative plasticizers (APs), and 1.44, 0.313, and 0.066 ng/g for the metabolites of PAEs, OPEs, and APs, respectively. Positive correlations between plasticizers and their corresponding primary metabolites, as well as correlations among the oxidative metabolites of bis(2-ethylhexyl) phthalate (DEHP) and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), were observed, indicating that infant hair retained the major phase-I metabolism of the target plasticizers. While no positive correlations were found in parent compounds or their primary metabolites between paired infant hair and meconium, significant positive correlations were observed among secondary oxidative metabolites of DEHP and DINCH in hair and meconium, suggesting that the primary metabolites in meconium come from hydrolysis of plasticizers in the fetus but most of the oxidative metabolites come from maternal-fetal transmission. The parent compound/metabolite ratios in infant hair showed a decreasing trend across pregnancy, suggesting in utero accumulation and deposition of plasticizers. To the best of our knowledge, this study is the first to report in utero exposure to both parent compounds and metabolites of plasticizers by using paired infant hair and meconium as noninvasive biomonitoring matrices and provides novel insights into the fetal biotransformation and accumulation of plasticizers across pregnancy.

Emerging global trends and development in forensic toxicology: A review

This study conducts a comprehensive analysis of forensic toxicology research trends, publication patterns, author's contributions, and collaboration. Utilizing the Scopus database, we scrutinized 3259 articles across 348 journals spanning from 1975 to 2023. Analysis employed diverse software tools such as VOSviewer, RStudio, MS Excel, and MS Access to dissect various publication aspects. We observed a notable surge in publications post-2007, indicating heightened research interest. Leading contributors included the United States, Germany, and Italy, with Logan B.K. emerging as the most prolific author. Forensic Science International stood out as the primary journal, publishing 888 articles and accruing significant citations. Keyword co-occurrences such as "forensic toxicology," "forensic science," and "toxicology" underscored core thematic areas in the field. Moreover, extensive research collaboration, especially among Western nations in Europe, was evident. This study underscores the imperative for enhanced collaboration between developing and developed nations to foster further advancements in forensic science. Strengthened partnerships can catalyze innovation, facilitate knowledge dissemination, and address emerging challenges, thereby propelling the field of forensic toxicology toward new frontiers of discovery and application.

Applicability of a Chemiluminescence Immunoassay to Screen Postmortem Bile Specimens and Its Agreement with Confirmation Analysis

Bile has emerged as an alternative matrix for toxicological investigation of drugs in suspected forensic cases of overdose in adults and intoxications in children. Toxicological investigation consists in screening and, subsequently, confirming the result with specific techniques, such as liquid chromatography with tandem mass spectrometry (LC-MS/MS). As there is no screening test on the market to test postmortem bile specimens, the novelty of this study was in investigating the applicability of a chemiluminescence immunoassay, designed for other matrices and available on the market, on bile and validate its use, testing the agreement with LC-MS/MS analysis. Bile specimens were obtained from 25 forensic cases of suspected death from overdose and intoxication. Sample preparation for bile screening consists simply in centrifugation and dilution. Confirmation analysis allows simultaneous identification of 108 drugs and was validated on bile. Kappa analysis assessed a perfect agreement (0.81-1) between the assays for benzodiazepines, methadone, opiates, cocaine, oxycodone, cannabinoids, buprenorphine and pregabalin; a substantial agreement (0.41-0.6) was reported for barbiturates. No agreement was assessed for amphetamines, due to an abundance of putrefactive amines in postmortem specimens. In conclusion, this fast and easy immunoassay could be used for initial screening of bile specimens, identifying presence of drugs, except amphetamines, with reliability.

Direct-To-Definitive Urine and Oral Fluid Test Results for Unscreened and Rarely Screened Drugs in Individuals Applying for Methadone Treatment in 7 U.S. States

The standard protocol in addiction treatment/pain management is to conduct immunoassay screens for major drugs subject to misuse, followed by confirmatory testing of positive results. However, this may miss unscreened or rarely screened drugs that could pose risks, especially to polydrug users. We sought to determine the prevalences of unscreened/rarely screened drugs in a sample of individuals misusing drugs in 7 U.S. states, and to compare the results of urine vs. oral testing for these drugs by direct-to-definitive liquid chromatography/tandem mass spectrometry (LC-MS-MS). The five drugs with the highest prevalences were: gabapentin (16.8%), quetiapine (6.2%), chlorpheniramine (5.3%), hydroxyzine (4.9%), and ephedrine (3.5%). All have clinical significance as indicated by severity of possible side effects, interactions with other drugs, and/or misuse potential. Drugs were generally detected more frequently in oral fluid than urine, but gabapentin was more frequently detected in urine. The prevalences of the included drugs seem high enough, and their clinical significance important enough, to warrant consideration of expanding clinical drug test panels, either by direct-to-definitive testing or the addition of selected immunoassay screens when available. Oral fluid was usually more suitable than urine as the test matrix, given the higher rates of detection in oral fluid for most substances included in this study.

Immunoassay testing for barbiturates using alternative matrices in postmortem tissues from cats and dogs

The barbiturate drug pentobarbital is commonly used by veterinarians for the euthanasia of domestic animals. During the veterinary forensic autopsy, it is sometimes necessary to determine whether the animal was chemically euthanized with pentobarbital. The use of a human immunochromatographic test for barbiturate screening utilizing dog or cat urine has been previously validated; however, the use of alternative matrices for this purpose is yet to be explored when urine is not available. Postmortem heart, liver, spleen, skeletal muscle, blood and/or urine samples from 20 dogs and 26 cats with a reported chemical euthanasia status were processed using two different methods, bead homogenization and sonication, and screened for barbiturates using a human immunochromatographic test. There was 100% agreement of the immunochromatographic test results using the sonication method with the reported euthanasia status of both dogs and cats. Using the bead homogenization method, agreement with the reported euthanasia status was 93.3% and 96.7% for dogs and cats, respectively, due to invalid test results from four dog and two cat samples. A subset of liver samples (10 canine and 10 feline) was analyzed via gas chromatography-mass spectrometry, and there was 100% agreement between the immunochromatographic test results and gas chromatography-mass spectrometry results for both cats and dogs. Overall, our results support the use of a variety of alternative matrices for barbiturate screening in cats and dogs.

Quetiapine-Related Deaths: In Search of a Surrogate Endpoint

Quetiapine is a second-generation antipsychotic drug available for two and half decades. Due to increased misuse, prescription outside the approved indications, and availability on the black market, it is being encountered in medicolegal autopsies more frequently. For instance, it has been linked to increased mortality rates, most likely due to its adverse effects on the cardiovascular system. Its pharmacokinetic features and significant postmortem redistribution challenge traditional sampling in forensic toxicology. Therefore, a systematic literature review was performed, inclusive of PubMed, the Web of Science-core collection, and the Scopus databases; articles were screened for the terms "quetiapine", "death", and "autopsy" to reevaluate each matrix used as a surrogate endpoint in the forensic toxicology of quetiapine-related deaths. Ultimately, this review considers the results of five studies that were well presented (more than two matrices, data available for all analyses, for instance). The highest quetiapine concentrations were usually measured in the liver tissue. As interpreted by their authors, the results of the considered studies showed a strong correlation between some matrices, but, unfortunately, the studies presented models with poor goodness of fit. The distribution of quetiapine in distinct body compartments/tissues showed no statistically significant relationship with the length of the postmortem interval. Furthermore, this study did not confirm the anecdotal correlation of peripheral blood concentrations with skeletal muscle concentrations. Otherwise, there was no consistency regarding selecting an endpoint for analysis.

The use of vitreous humour as a potential source of DNA for postmortem identification in forensic science

Vitreous humour (VH) is routinely collected for toxicological analyses. However, only a few studies have examined its possible use in genotyping. Because of its isolation from the rest of the body, later onset of postmortem changes, and availability, VH could be a potential source of DNA for postmortem identification and other molecular analyses in forensic genetics. During forensic autopsies, samples of different VH volumes (5 ml, 4 ml, 3 ml, 2 ml, 1 ml, and 0.5 ml) were taken from 66 cadavers 24-48 h after death. DNA was also isolated from the samples immediately after collection and after a specific time of storage (1, 2, and 6 months). DNA was isolated using phenol‒chloroform‒isoamyl alcohol (PCI), and the yield and purity of the obtained DNA were determined spectrophotometrically using a FastGene NanoView Photometer. The integrity of the isolated DNA molecule was determined by PCR amplification of the hTERT (113 bp) gene. The results showed that VH could be a reliable source of genetic material for forensic analysis, and the method used for DNA extraction was effective. The yield of the isolated DNA ranged from 6.20 to 609.5 ng/µl, and the purity of the samples was 1.24-2.34. The isolated DNA concentration and integrity depend on the sample volume, but the DNA purity does not. It is also shown that DNA can be extracted from VH samples that have been stored for up to 6 months at - 20 °C. Therefore, using VH can be a valuable material for DNA identification.

Sensors in the Detection of Abused Substances in Forensic Contexts: A Comprehensive Review

Forensic 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.

Nitrites: An Old Poison or a Current Hazard? Epidemiology of Intoxications Covering the Last 100 Years and Evaluation of Analytical Methods

In recent times, there has been a concerning and noteworthy rise in the global use of sodium nitrite for suicidal purposes. This is facilitated either through the employment of specialized "suicide kits" or by acquiring sodium nitrite through alternative means. Additionally, another occurrence contributing to nitrite poisoning is the recreational utilization of nitrites in the form of volatile aliphatic esters of nitrous acid, commonly referred to as "poppers". Based on current available papers and reports on the subject of nitrates, nitrites, and poppers intoxications, an epidemiological analysis and evaluation of analytical methods were performed. A total of 128 papers, documenting a collective count of 492 intoxication cases, were identified. Additionally, in order to complete the epidemiological profile of nitrite poisoning, the authors briefly examined six cases of nitrite intoxication that were under investigation in our laboratory. Furthermore, a review of nitrite poisoning cases over the past 100 years shows that the old poison is still in use and poses a substantial risk to society.

Determination of Prostaglandins (Carboprost, Cloprostenol, Dinoprost, Dinoprostone, Misoprostol, Sulprostone) by UHPLC-MS/MS in Toxicological Investigations

Prostaglandins have stimulative influence on the human uterus and therefore were introduced to medical treatment in reproductive healthcare as labor inductors or abortifacients. The UHPLC-ESI-QqQ-MS/MS method was developed for six prostaglandins: carboprost, cloprostenol, dinoprost (PGF2α), dinoprostone (PGE2), misoprostol and sulprostone (substances for pregnancy termination) in pharmaceutical samples and was applied for the toxicological examination of pills containing misoprostol (collected during gynecological examination). There were used two internal standards: misoprostol-d5 and PGF2α-d4. The quantification of analytes was performed in the MRM mode. The linearity of method was in the range from 0.1 to 10 µg/mL, with a coefficient of determination above 0.997 (R2) for each compound. The precision and accuracy values did not exceed ±5.0%. Analysis of the pills revealed the presence of two substances: misoprostol and diclofenac. Misoprostol and diclofenac dose per sample were as follows: 608.8 ng (sample 1), 708.4 ng (sample 2), 618.8 ng (sample 3) and 67.7 mg (sample 1), 65.3 mg (sample 2) 67.3 mg (sample 3), respectively. A simple, precise and reliable method can be applied for routine examinations in terms of clinical and forensic toxicology examinations as well as in quality control of drugs for pharmaceutical purposes (original drugs and counterfeit medications).

Cork sheet as an efficient biosorbent for forensic toxicology: Application to vitreous humor analysis

There is an increasing number of people affected worldwide by mental health disorders, such as depression and anxiety. One of the main courses of treatment, along with psychotherapy, is the use of psychoactive medications, like antidepressants and benzodiazepines. Also, the unprescribed use of these substances is a concerning public health issue. Hence, the analysis of psychotropic medications is mandatory in postmortem toxicology and various biological samples can be used for this detection, among them the vitreous humor (VH) stands out. Also, there is a demand for more sustainable and more efficient extraction methodologies according to green chemistry. An example is solid phase microextraction techniques (SPME), which use a solid sorbent and small solvent amounts. Biosorbents are substances of natural origin with sorptive properties, and they have been successfully used in SPME in environmental toxicology for water analysis, mainly. This study aimed to develop a sustainable, fast, cheap and simple SPME methodology using cork sheet strips as a biosorbent, to extract antidepressants, benzodiazepines and others from VH samples by liquid chromatography coupled to tandem mass spectrometry. The extraction was conducted in a 96-well plate using 200 µL of VH and optimization of relevant parameters for extraction was performed. For solvent optimization, two simplex-centroid experiments were planned for extraction and desorption and to evaluate time and pH, a Doehlert design experiment was performed. The analytical method for the determination and quantification of 17 substances was validated. The quantification limits were 5 ng/mL for all analytes and the calibration curves were linear between 5 and 30 ng/mL. This study was able to develop an efficient, cheap, simple and fast microextraction method for 17 analytes in VH, using strips of cork sheet for extraction and a 96-well plate as a container. Furthermore, this approach system could be automated for routine toxicology laboratories.

GC-MS/MS Determination of Synthetic Cathinones: 4-chloromethcathinone, N-ethyl Pentedrone, and N-ethyl Hexedrone in Oral Fluid and Sweat of Consumers under Controlled Administration: Pilot Study

This study presents a validated GC-MS/MS method for the detection and quantification of 4-chloromethcathinone or clephedrone (4-CMC), N-ethyl Pentedrone (NEP), and N-ethyl Hexedrone (NEH, also named HEXEN) in oral fluid and sweat and verifies its feasibility in determining human oral fluid concentrations and pharmacokinetics following the administration of 100 mg of 4-CMC orally and 30 mg of NEP and NEH intranasally. A total of 48 oral fluid and 12 sweat samples were collected from six consumers. After the addition of 5 μL of methylone-d₃ and 200 μL of 0.5 M ammonium hydrogen carbonate, an L/L extraction was carried out using ethyl acetate. The samples, dried under a nitrogen flow, were then derivatized with pentafluoropropionic anhydride and dried again. One microliter of the sample reconstituted in 50 μL of ethyl acetate was injected into GC-MS/MS. The method was fully validated according to international guidelines. Our results showed how, in oral fluid, the two cathinones taken intranasally were absorbed very rapidly, within the first hour, when compared with the 4-CMC which reached its maximum concentration peak in the first three hours. We observed that these cathinones were excreted in sweat in an amount equivalent to approximately 0.3% of the administered dose for 4-CMC and NEP. The total NEH excreted in sweat 4 h after administration was approximately 0.2% of the administered dose. Our results provide, for the first time, preliminary information about the disposition of these synthetic cathinones in the consumers' oral fluid and sweat after controlled administration.

Identification and quantification of diphenhydramine, haloperidol, and its metabolite, reduced haloperidol in a saponified brain specimen that was immersed in the sea water for more than 10 years

In forensic toxicology, blood and urine specimens are commonly used for detecting and quantifying drugs and their metabolites. When the cadaver is so damaged or decomposed such that the specimens mentioned above cannot be collected, it is necessary to perform drug analysis using alternative specimens such as hair, nails, oral fluids and meconium. Adipocere is resistant to further degradation; it is thus possible to be used as an alternative specimen to analyze drugs and their metabolites. Some researchers indeed have reported drug concentrations in saponified samples that were collected years after decedents' deaths. In this study, we subjected saponified brain, which remained under sea for over 10 years after death, to forensic toxicological analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Using product ion scan analysis, we confirmed the presence of diphenhydramine, haloperidol, and reduced haloperidol, a metabolite of haloperidol. In addition, drugs and metabolite quantification were performed using the standard addition method. Correlation coefficients of the calibration curves were over 0.98. Analyte concentrations in the saponified brain were as follows: diphenhydramine was 1.84 ng/g, haloperidol was 1.30 ng/g, and reduced haloperidol was 3.02 ng/g. Our results suggest that it can be possible to quantify not only parent drugs but also their metabolites in saponified brain. These findings indicate that saponified tissues could be applied as alternative specimens for forensic toxicology, and could be useful as supporting information for victim identification.

Epiglottis Cartilage, Costal Cartilage, and Intervertebral Disc Cartilage as Alternative Materials in the Postmortem Diagnosis of Methanol Poisoning

Alternative materials for postmortem diagnosis in the case of fatal poisonings are much needed when standard materials, such as blood and urine, are unavailable. The study presents a case of fatal mass methanol intoxication resulting from industrial alcohol consumption. The study aimed to determine methanol and formic acid concentrations in epiglottis cartilage, costal cartilage, and intervertebral disc cartilage and to analyze the correlation between their concentrations in cartilage tissues and the femoral blood. Methanol and formic acid concentrations in samples collected from 17 individuals (n = 17) were estimated using gas chromatography with flame ionization detection (GC-FID). Methanol concentration in the costal cartilage correlated with its concentration in the femoral blood (r = 0.871). Similar correlations were found for epiglottis cartilage (r = 0.822) and intervertebral disc cartilage (r = 0.892). Formic acid concentration in the blood correlated only with its concentration in urine (r = 0.784) and the epiglottis (r = 0.538). Cartilage tissue could serve as an alternative material for methanol analyses in postmortem studies. Formic acid, a methanol metabolite, does not meet the requirements for its presence determination in cartilage tissues.

Hybrid volatilomics in cancer diagnosis by HS-GC-FID fingerprinting

Assessing volatile organic compounds (VOCs) as cancer signatures is one of the most promising techniques toward developing non-invasive, simple, and affordable diagnosis. Here, we have evaluated the feasibility of employing static headspace extraction (HS) followed by gas chromatography with flame ionization detector (GC-FID) as a screening tool to discriminate between cancer patients (head and neck-HNC,n= 15; and gastrointestinal cancer-GIC,n= 19) and healthy controls (n= 37) on the basis of a non-target (fingerprinting) analysis of oral fluid and urine. We evaluated the discrimination considering a single bodily fluid and adopting the hybrid approach, in which the oral fluid and urinary VOCs profiles were combined through data fusion. We used supervised orthogonal partial least squares discriminant analysis for classification, and we assessed the prediction power of the models by analyzing the values of goodness of prediction (Q²Y), area under the curve (AUC), sensitivity, and specificity. The individual models HNC urine, HNC oral fluid, and GIC oral fluid successfully discriminated between healthy controls and positive samples (Q²Y = 0.560, 0.525, and 0.559; AUC = 0.814, 0.850, and 0.926; sensitivity = 84.8, 70.2, and 78.6%; and specificity = 82.3; 81.5; 87.5%, respectively), whereas GIC urine was not adequate (Q²Y = 0.292, AUC = 0.694, sensitivity = 66.1%, and specificity = 77.0%). Compared to the respective individual models, Q²Y for the hybrid models increased (0.623 for hybrid HNC and 0.562 for hybrid GIC). However, sensitivity was higher for HNC urine and GIC oral fluid than for hybrid HNC (75.6%) and hybrid GIC (69.8%), respectively. These results suggested that HS-GC-FID fingerprinting is suitable and holds great potential for cancer screening. Additionally, the hybrid approach tends to increase the predictive power if the individual models present suitable quality parameter values. Otherwise, it is more advantageous to use a single body fluid for analysis.

Analysis of Stimulants in Sweat and Urine Using Disposable Pipette Extraction and Gas Chromatography Coupled to Mass Spectrometry in the Context of Doping Control

Urine is initially collected from athletes to screen for the presence of illicit drugs. Sweat is an alternative sample matrix that provides advantages over urine including reduced opportunity for sample adulteration, longer detection-time window and non-invasive collection. Sweat is suitable for analysis of the parent drug and metabolites. In this study, a method was developed and validated to determine the presence of 13 amphetamine- and cocaine-related substances and their metabolites in sweat and urine using disposable pipette extraction (DPX) by gas chromatography coupled to mass spectrometry. The DPX extraction was performed using 0.1 M HCl and dichloromethane:isopropanol:ammonium hydroxide (78:20:2, v/v/v) followed by derivatization with N-methyl-N-(trimethylsilyl) trifluoroacetamide at 90°C for 20 min. DPX extraction efficiencies ranged between 65.0% and 96.0% in urine and 68.0% and 101.0% in sweat. Method accuracy was from 90.0% to 104.0% in urine and from 89.0% to 105.0% in sweat. Intra-assay precision in urine and in sweat were <15.6% and <17.8%, respectively, and inter-assay precision ranged from 4.70% to 15.3% in urine and from 4.05% to 15.4% in sweat. Calibration curves presented a correlation coefficient -0.99 for all analytes in both matrices. The validated method was applied to urine and sweat samples collected from 40 professional athletes who knowingly took one or more of the target illicit drugs. Thirteen of 40 athletes were positive for at least one drug. All the drugs detected in the urine were also detected in sweat samples indicating that sweat is a viable matrix for screening or confirmatory drug testing.

Application of Fabric Phase Sorptive Extraction (FPSE) Engaged to Tandem LC-MS/MS for Quantification of Brorphine in Oral Fluid

Brorphine (1-[1-[1-(4-bromophenyl) ethyl]-piperidin-4-yl]-1,3-dihydro-2H-benzo [d]imidazol-2-one) is one of the most recent novel synthetic opioids (NSOs) on the novel psychoactive substances (NPSs) market, involved in over 100 deaths in 2020. Brorphine is a substituted piperidine-benzimidazolone analogue that retains structural similarities to fentanyl, acting as a full agonist at the μ-opioid receptor. Oral Fluid (OF) is an alternative matrix, frequently analyzed for the detection of NPS. Fabric phase sorptive extraction (FPSE) is a superior, green-sample -preparation technology recently applied for drug analysis. This contribution presents the development and validation of a method, based on the application of FPSE and liquid chromatography-tandem mass spectrometry (LC-MS/MS), to determine/quantitate brorphine in OF. The method's linearity ranged between 0.05 and 50 ng/mL (R² = 0.9993), the bias ranged between 12.0 and 16.8%, and inter- and intra-day precisions ranged between 6.4 and 9.9%. Accuracy and extraction efficiency lied between 65 and 75%. LOD/LOQ were 0.015 ng/mL/0.05 ng/mL. Analyte's post-preparative stability was higher than 95%, while no matrix interferences and carryover between runs were observed. This is the first report introducing the application of FPSE for NPS determination, specifically, the quantification of brorphine in OF, thereby presenting a simple, rapid, sensitive, specific, effective, and reliable procedure engaged to LC-MS/MS that is suitable for routine application and the analysis of more NPSs.

Nanobiosensors for detection of opioids: A review of latest advancements

Opioids are generally used as analgesics in pain treatment. Like many drugs, they have side effects when overdosing and causeaddiction problems.Illegal drug use and misuse are becoming a major concern for authorities worldwide; thus, it is critical to have precise procedures for detecting them in confiscated samples, biological fluids, and wastewaters. Routine blood and urine tests are insufficient for highly selective determinations and can cause cross-reactivities. For this purpose, nanomaterial-based biosensors are great tools to determine opioid intakes, continuously monitoring the drugs with high sensitivity and selectivity even at very low sample volumes.Nanobiosensors generally comprise a signal transducer nanostructure in which a biological recognition molecule is immobilized onto its surface. Lately, nanobiosensors have been extensively utilized for the molecular detection of opioids. The usage of novel nanomaterials in biosensing has impressed biosensing studies. Nanomaterials with a large surface area have been used to develop nanobiosensors with shorter reaction times and higher sensitivity than conventional biosensors. Colorimetric and fluorescence sensing methods are two kinds of optical sensor systems based on nanomaterials. Noble metal nanoparticles (NPs), such as silver and gold, are the most frequently applied nanomaterials in colorimetric techniques, owing to their unique optical feature of surface plasmon resonance. Despite the progress of an extensive spectrum of nanobiosensors over the last two decades, the future purpose of low-cost, high-throughput, multiplexed clinical diagnostic lab-on-a-chip instruments has yet to be fulfilled. In this review, a concise overview of opioids (such as tramadol and buprenorphine, oxycodone and fentanyl, methadone and morphine) is provided as well as information on their classification, mechanism of action, routine tests, and new opioid sensing technologies based on various NPs. In order to highlight the trend of nanostructure development in biosensor applications for opioids, recent literature examples with the nanomaterial type, target molecules, and limits of detection are discussed.

Homemade Pipette Tip Solid-Phase Extraction for the Simultaneous Determination of 40 Drugs of Abuse in Urine by Liquid Chromatography–Tandem Mass Spectrometry

Pipette tip solid-phase extraction facilitates the handling of low-volume samples and organic solvents in order to achieve more environmentally friendly pre-treatment sample techniques. The use of pipette tip extraction was examined for the quick and simple determination of a heterogeneous group of 40 drugs of abuse and some of their metabolites in urine by liquid chromatography coupled to tandem mass spectrometry. Several parameters were studied and optimized, including those which can affect extraction efficiencies, such as the amount of sorbent and the volumes and number of aspirating/dispensing cycles of the sample and organic solvents. The linear range of this method was between the quantification limit and 75 or 100 ng mL−1. Detection limits between 0.025 and 0.500 ng mL−1 and quantification limits from 0.100 to 1.500 ng mL−1 were achieved, which are adequate to determine the studied compounds in urine from drug users. Finally, in order to prove its suitability in toxicological and forensic analyses, the method was successfully applied to 22 urine specimens from women who were starting a detoxification program. Cocaine was the most frequently detected substance, as its presence or the presence of its main metabolite was found in 86% of the analyzed samples.

Development of analytical method for the determination of methylphenidate, the analog ethylphenidate and their metabolite ritalinic acid in oral fluid samples by micro-QuEChERS and liquid chromatography-tandem mass spectrometry

The aim of this study was to develop a quantitative method for the analysis of methylphenidate, the analog ethylphenidate and their metabolite ritalinic acid in oral fluid, using micro-QuEChERS extraction and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Oral fluid samples were collected with Quantisal™ device, extracted by micro-QuEChERS technique and analyzed by LC-MS/MS. The developed method met the validation criteria of Academy Standards Board (ASB) Standard Practices for Method Validation in Forensic Toxicology (Standard 036, 2019) with limits of detection and quantification of 0.5 ng/mL and calibration curve from 0.5 to 50 ng/mL. Within-run imprecision was greater than 18.7% while between-run imprecision was greater than 17.0 % for all analytes. Bias did not vary more than 7.7 %. No evidence of carryover was found. Stability studies presented satisfactory results for 24 h on autosampler (10 °C), after 3 cycles of freeze/thaw, 7 days on freezer (-20 °C) and until 7 days on refrigerator (4 °C) for methylphenidate. The validated method was further successfully applied to the analysis of 5 authentic oral fluid samples collected from volunteers at parties and music festivals from different cities in Brazil. Four samples had positive results for methylphenidate and ritalinic acid, and only one sample was positive for methylphenidate. Ethylphenidate was not detected in the samples. The method showed acceptable analytical performance and is environmentally friendly, requiring reduced use of solvents and reagents, with potential to be applied to clinical and forensic analyses.

A Forensic Diagnostic Algorithm for Drug-Related Deaths: A Case Series

The best evidence provided in the literature worldwide suggests the importance of harmonizing the investigation in drug-related fatalities. In this study, the application of a multidisciplinary approach in eight cases of drug-related deaths is presented. Although death scene findings could be highly suggestive of drug intoxication, external examination and toxicological screening test alone are insufficient. There are several variables, and it is not always easy to give the proper interpretation of the drug detection. A complete autopsy is necessary to correctly complete organ and tissues sampling for further histological and toxicological studies and obtain body fluids. The use of peripheral blood is recommended to avoid artifacts. The collection of many specimens is warranted to get more responses. The sampling aims to provide a picture of the distribution of the substance in the body. The sample and the selection of the drugs and the matrices to investigate are case-dependent. The presented diagnostic algorithm provides the coroner with all the elements to investigate drug-related deaths and cooperate with toxicologists. Toxicological forensic diagnosis is still extremely heterogeneous in regional and national contexts. Funding for method development, research, networking, facilities, and technologies improvement is mandatory to standardize the toxicological investigation.

Ayahuasca as a Decoction Applied to Human: Analytical Methods, Pharmacology and Potential Toxic Effects

Ahyahuasca is a term commonly used to describe a decoction prepared by cooking the bark or crushed stems of the liana Banisteriopsis caapi (contains β-carbolines) alone or in combination with other plants, most commonly leaves of the shrub Psychotria viridis (contains N,N-dimethyltryptamine-DMT). More than 100 different plants can serve as sources of β-carbolines and DMT, which are the active alkaloids of this decoction, and therefore it is important to know the most accurate composition of the decoction, especially when studying the pharmacology of this plant. The aim was to summarize the latest sensitive methods used in the analysis of the composition of the beverage itself and the analysis of various biological matrices. We compared pharmacokinetic parameters in all of the studies where decoction of ayahuasca was administered and where its composition was known, whereby minimal adverse effects were observed. The therapeutic benefit of this plant is still unclear in the scientific literature, and side effects occur probably on the basis of pre-existing psychiatric disorder. We also described toxicological risks and clinical benefits of ayahuasca intake, which meant that the concentrations of active alkaloids in the decoction or in the organism, often not determined in publications, were required for sufficient evaluation of its effect on the organism. We did not find any post-mortem study, in which the toxicological examination of biological materials together with the autopsy findings would suggest potential lethality of this plant.

Developments in high-resolution mass spectrometric analyses of new psychoactive substances

The proliferation of new psychoactive substances (NPS) has necessitated the development and improvement of current practices for the detection and identification of known NPS and newly emerging derivatives. High-resolution mass spectrometry (HRMS) is quickly becoming the industry standard for these analyses due to its ability to be operated in data-independent acquisition (DIA) modes, allowing for the collection of large amounts of data and enabling retrospective data interrogation as new information becomes available. The increasing popularity of HRMS has also prompted the exploration of new ways to screen for NPS, including broad-spectrum wastewater analysis to identify usage trends in the community and metabolomic-based approaches to examine the effects of drugs of abuse on endogenous compounds. In this paper, the novel applications of HRMS techniques to the analysis of NPS is reviewed. In particular, the development of innovative data analysis and interpretation approaches is discussed, including the application of machine learning and molecular networking to toxicological analyses.