Optimization of Parallel Artificial Liquid Membrane Extraction for the Determination of Over 50 Psychoactive Substances in Oral Fluid Through UHPLC-MS/MS

Over the past decade, there has been a diversification of the psychoactive substances available among drug users, resulting in the expansion of a dynamic market of synthetic molecules that are challenging for drug of abuse testing. Multiclass analytical methods are useful to deal with these new psychoactive substances (NPS), but sample preparation can be difficult and generate significant amounts of chemical waste. The aim of this work was the development of a high-throughput microextraction method for the determination of 56 drugs belonging to different pharmacological classes in oral fluid (OF), including both traditional drugs and NPS. In the proposed workflow, the OF sample is cleaned-up by parallel artificial liquid membrane extraction (PALME) and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two hundred microliters of OF are mixed with 1800 μL of carbonate buffer 0.5 M (pH 12) and 0.4 g of sodium chloride and inserted into a donor plate; the acceptor plate embed a dodecylacetate-supported liquid membrane and an acceptor solution composed of 50 μL formic acid 0.1% in H2O: MeOH, 80:20 (v/v); the whole assemblage is placed on an orbital shaker for 120 min for extraction. A full factorial design has been employed for extraction optimization to make it suitable for LC-MS/MS. The developed method is an example of green chemistry and may be used for screening and quantitative purposes, with limits of detection ranging from 0.01 to 1.5 ng mL-1 and optimal performance in term of precision and accuracy for 49 out of 56 drugs tested.

Validation of an LC-MS-MS method for analysis of 58 drugs of abuse in oral fluid and method comparison with an established LC-HRMS method

Liquid chromatography-mass spectrometry (LC-MS) methods for detection of multiple drugs of abuse (DoA) in oral fluid (OF) samples are being implemented in many clinical routine laboratories. Therefore, there is a need to develop new multianalyte methods with simple sample pretreatment and short analysis times. The purpose of this work was to validate a method detecting 58 DoA to be used with two different OF sampling kits, the saliva collection system (SCS) from Greiner Bio-One and Quantisal from Immunalysis, using the same sample pretreatment and analytical method. A set of 110 samples collected with the SCS kit was further compared to an high-resolution mass spectrometry (LC-HRMS) method in another laboratory. The method was successfully validated, with precision and accuracy of ≤15% and z-scores of <2 for external controls. Using a sensitive LC-MS-MS instrument, the detection limits were <1 µg/l in neat oral fluid. In the comparative study between the LC-MS-MS and LC-HRMS methods using SCS samples, a good agreement was observed. Discrepancies were limited to lower concentration ranges, attributable to differences in cut-off thresholds between the methods. This work contributes to the development of LC-MS multianalyte methods for OF samples, which are suitable for clinical routine laboratories.

Reliability of roadside oral fluid testing devices for ∆9-tetrahydrocannabinol (∆9-THC) detection

Driving under the influence of cannabis (DUIC) is increasing worldwide, and cannabis is the most prevalent drug after alcohol in impaired driving cases, emphasizing the need for a reliable traffic enforcement strategy. ∆9-tetrahydrocannabinol (THC) detection in oral fluid has great potential for identifying recent cannabis use; however, additional data are needed on the sensitivities, specificities, and efficiencies of different oral fluid devices for detecting cannabinoids at the roadside by police during routine traffic safety enforcement efforts. At the roadside, 8945 oral fluid THC screening tests were performed with four devices: AquilaScan®, Dräger DrugTest®, WipeAlyser Reader®, and Druglizer®. A total of 530 samples screened positive for THC (5.9%) and were analyzed by liquid chromatography-tandem mass spectrometry at multiple cutoff concentrations (2 ng/mL, 10 ng/mL, and manufacturers' recommended device cutoffs) to investigate device performance. Results varied substantially, with sensitivities of 0%-96.8%, specificities of 89.8%-98.5%, and efficiencies of 84.3%-97.8%. The Dräger DrugTest® outperformed the other devices with a 96.8% sensitivity, 97.1% specificity, and 97.0% efficiency at a 5-ng/mL LC-MS/MS confirmation cutoff. The WipeAlyser Reader® had good performance with a 91.4% sensitivity, 97.2% specificity, and 96.4% efficiency. AquilaScan® and Druglizer® had unacceptable performance for cannabinoid detection, highlighted by sensitivity <13%. The choice of roadside oral fluid testing device must offer good analytical performance for cannabinoids because of its high prevalence of use and impact on road safety.

Environmentally friendly screen-printed electrodes for the selective detection of 4-bromo-2,5-dimethoxyphenethylamine (2C-B) in forensic analysis

In response to the growing need for sustainable analytical methods, this study explores the repurposing of screen-printed electrodes (SPEs) that would otherwise be discarded. This involves recoating the working electrode surface with a graphite (Gr) and chitosan (CTS) dispersion, creating a reusable SPE (SPE-Gr/CTS). Demonstrating its utility, SPE-Gr/CTS was employed for the detection of 4-bromo-2,5-dimethoxyphenethylamine (2C-B), a phenylethylamine commonly used for recreational proposes. Identifying 2C-B in fluid oral and seized samples is of great interest for forensic and toxicological applications. The 2C-B detection using SPE-Gr/CTS was optimized in Britton-Robinson buffer solution (0.1 mol L-1) at pH 2.0, employing square-wave adsorptive stripping voltammetry. The electrochemical behavior of 2C-B on SPE-Gr/CTS exhibited one irreversible oxidation and a reversible redox process. The proposed method presented a dynamic linear range for 2C-B determination (0.05 to 7.5 μmol L-1) with a low LOD (0.015 μmol L-1). Moreover, the stability of 2C-B electrochemical responses on SPE-Gr/CTS was confirmed using the same or different electrodes (N = 3), with a relative standard deviation of less than 5.0%. Interference studies with seventeen other illicit drugs and adulterants demonstrated that the proposed method is selective for 2C-B detection even in the presence of these substances. Real seized and oral fluid samples containing 2C-B were analyzed using this method, and the results were confirmed by LC-MS. The proposed device demonstrates to be an environmentally friendly and selective sensor for 2C-B detection in forensic analysis, offering a rapid and straightforward screening method for seized and biological samples. In addition, a portable and sensitive determination of 2C-B in forensic samples is presented with minimal sample consumption (50 μL).

Development and validation of a simple chromatographic method to screen oral fluid samples for drugs in DUID investigations

A simple and rapid qualitative chromatographic method with a unique extraction approach was developed and validated to screen oral fluid samples for 31 compounds in driving under the influence of drugs investigations. The scope and sensitivity of the method meets or exceeds Tier I recommendations established by the National Safety Council's Alcohol, Drugs and Impairment Division. Since this is a targeted chromatographic screen (rather than an immunoassay), cutoffs were set to match the confirmation levels in the recommendations. Sample preparation involved a single-step liquid-liquid extraction procedure, using a mixture of methyl tert-butyl ether, isopropanol, and hexane and was applied to samples collected with the Quantisal™ device. Instrument analysis was conducted by liquid chromatography-tandem mass spectrometry, using a Restek Raptor™ biphenyl column for chromatographic separations and a total run time of 8 min. Validation results met all requirements of ANSI/ASB Standard 036 (1st edition)-Standard Practices for Method Validation in Forensic Toxicology.

Detection and quantification of selected cannabinoids in oral fluid samples by protein precipitation and LC-MS/MS

Cannabis is the most widely consumed illicit drug worldwide. As consumption rates increase, partially due to the decriminalization of its use for medicinal and recreational purposes, analytical methods for monitoring different cannabinoids in several biological matrices have been developed. Herein, a simple and fast extraction procedure to extract natural cannabinoids from oral fluid (OF) samples was developed and fully validated according to the ANSI/ASB 2019 Standard Practices for Method Validation in Forensic Toxicology. Using only 0.2 mL of neat OF, the analytes [Δ9-tetrahidrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (THC-OH), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH), cannabinol (CBN) and cannabidiol (CBD)] were extracted by protein precipitation with a mixture of methanol:acetonitrile (80:20, v/v); the extracts were centrifuged, evaporated to dryness and reconstituted in 100 µL of methanol. Analysis was performed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The developed methodology produced linear results for all compounds, with working ranges of 0.1-50 ng/mL for THC, 0.5-50 ng/mL for THC-OH, CBN and CBD, and 0.05-1 ng/mL for THC-COOH. Ion suppression was observed for THC, CBN and CBD, which did not impair sensitivity considering the low limits of quantification (LOQs) and limits of detection (LODs) obtained (which varied between 0.05 and 0.5 ng/mL). The extraction procedure produced great recoveries, and the compounds were stable. No interferences were found, and the method proved to be extremely fast, selective, precise, and accurate for use in routine analysis. The method was successfully applied to authentic samples.

Technical and health governance aspects of the external quality assessment system for classical and new psychoactive substances analysis testing in blood

New psychoactive substances (NPS) are uncontrolled analogues of existing drugs or newly synthesized chemicals that exhibit psychopharmacological effects. Due to their diverse nature, composition, and increasing prevalence, they present significant challenges to the healthcare system and drug control policies. In response, healthcare system laboratories have developed analytical methods to detect NPS in biological samples. As a Regional Reference Centre, the Sicilian CRQ Laboratory (Regional Laboratory for Quality Control) developed and conducted an External Quality Assessment (EQA) study to assess, in collaboration with the Istituto Superiore di Sanità (ISS), the ability of different Italian laboratories to identify NPS and traditional drugs of abuse (DOA) in biological matrices. Two blood samples were spiked with substances from various drug classes, including synthetic cannabinoids, cathinones, synthetic opiates, and benzodiazepines, at concentrations ranging from 2 to 10 ng/mL. The blood samples were freeze-dried to ensure the stability of DOA and NPS. Twenty-two laboratories from the Italian healthcare system participated in this assessment. The information provided by the laboratories during the registration in an in-house platform included a general description of the laboratory, analytical technique, and the chosen panels of analytes. The same platform was employed to collect and statistically analyze the data and record laboratory feedback and comments. The evaluation of the results revealed that the participating laboratories employed three different techniques for analyzing the samples: GC-MS, LC-MS, and immunoenzymatic methods. Approximately 90 % of the laboratories utilized LC-MS techniques. Around 40 % of false negative results were obtained, with the worst results in the identification of 5-chloro AB PINACA. The results showed that laboratories that used LC-MS methods obtained better specificity and sensitivity compared to the laboratories using other techniques. The results obtained from this first assessment underscore the importance of external quality control schemes in identifying the most effective analytical techniques for detecting trace molecules in biological matrices. Since the judicial authorities have not yet established cut-off values for NPS, this EQA will enable participating laboratories to share their analytical methods and expertise, aiming to establish common criteria for NPS identification.

Target analysis of psychoactive drugs in oral fluid by QuEChERS extraction and LC-MS/MS

This study aimed to validate a modified QuEChERS method, followed by liquid chromatography-tandem mass spectrometry, for the determination of 51 psychoactive substances and screening of 22 ones in oral fluid from electronic dance music party (EDM) attendees. Unstimulated oral fluid was collected in a polypropylene tube and stored in a glass vial at -20 ºC. The sample was extracted with acetonitrile:water and MgSO4/NaOAc, followed by cleanup with primary secondary amine and MgSO4. The effectiveness of the sample storage conditions was shown to be comparable to when the Quantisal™ buffer was used, with no substantial concentration loss (< 15%) for all the substances after up to 72 hours at -20º C. The method was satisfactorily validated, with limits of detection (LOD) and quantification (LOQ) ranging from 0.04 to 0.5 ng/mL and 0.1-1.5 ng/mL, respectively, and was applied to the analysis of 62 real samples. The main substances detected were 3,4-methylenedioxymethamphetamine (MDMA) (<0.5-829 ng/mL) and/or methylenedioxyamphetamine (MDA) (10.1 - 460.6 ng/mL), found in 27 samples, and cocaine (13.0-407.3 ng/mL) and its metabolites (benzoylecgonine 0.17-214.1 ng/mL; ecgonine methyl ester 1.8-150.1 ng/mL) in eight samples. Methamphetamine (11-439 ng/mL) was detected in eight samples, along with MDMA and MDA; eutylone was detected in two cases (4.7 and 24.1 ng/mL) reported as "ecstasy" ingestion. A comparison between self-reported drug use and results of oral fluid analysis indicated that the use of illicit substances is often underreported among EDM attendees, who are often unaware of the substances they consume.

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.

SPE-UHPLC-ESI-MS/MS Analysis of Cocaine and Its Metabolites in Conventional and Alternative Biological Specimens: Application to Real Samples

An increase in cocaine abuse has been observed globally since the past decade. Cocaine is among the commonly abused stimulants used for recreational purposes. In this study, the SPE-UHPLC-MS/MS method was developed and validated to be applied on real specimens of 20 chronic cocaine abusers to quantify cocaine/metabolites in conventional as well as alternative biological matrices. Cocaine was extracted from biological specimens using solid-phase extraction followed by liquid chromatography tandem mass spectrometry analysis. Chromatographic separation was achieved on a Poroshell120EC-18 column (2.1 mm × 50 mm, 2.7 μm particle size) using water-acetonitrile in 0.1% formic acid as a mobile phase in gradient elution mode. The flow rate of the mobile phase was 0.5 mL/min with a gradient varying the percentage of acetonitrile linearity ranging 15-95% in 6.0 min acquisition time, and the injection volume was set at 5 μL. Positive electrospray ionization with multireaction ion monitoring mode using two ion transitions for cocaine/metabolites and one for cocaine-d3 was employed. The quantification method demonstrated good linear ranges of 0.025-250 ng/mL in blood, urine, and oral fluid (ng/mg for hair and nail) with a ≥0.991% determination coefficient. The detection limit and lower quantification limit were 0.005 and 0.025 ng/mL in all matrices, respectively. The mean extraction recovery and ionization suppression ranged from 89.3 to 99.8% and -4.6 to -14.4% in the studied matrices. Within-run and between-days precisions were 1.8-7.2% and 1.9-6.1%, respectively. This study will not only help in quantifying cocaine/metabolites in alternative specimens (hair, nail, and oral fluid) but also guide clinical and forensic toxicologists in interpretation of exhumation cases. Furthermore, multiple specimens' analyses can be of significance in estimating the time/manner of drug exposure, in confirming the results of laboratories in cases of doubtful clinical histories, or in aiding medico-legal investigations.

Solvent-free parallel artificial liquid membrane extraction for drugs of abuse in plasma samples using LC-MS/MS

BACKGROUND

Parallel artificial liquid membrane extraction (PALME) is a 96-well plate setup variant of liquid-phase microextraction. Basic or acidic analytes are extracted in neutral form from the sample, through a supported liquid membrane (SLM), and into aqueous acceptor. PALME is already considered a green extraction technique, but in the current conceptual work, we sought to make it even greener by replacing the use of organic solvents with essential oils (EO). PALME was combined with LC-MS/MS for analysis of plasma samples and multiple drugs of abuse with toxicological relevance (amphetamines, phenethylamines, synthetic cathinones, designer benzodiazepines, ayahuasca alkaloids, lysergic acid diethylamide, and ketamine).

RESULTS

Fourteen EO were compared to organic solvents frequently used in PALME. The EO termed smart & sassy yielded the best analyte recovery for all drugs studied and was thus selected as SLM. Then, factorial screening and Box-Behnken were employed to optimize the technique. The extraction time, concentration of base, sample volume, and percentage of trioctylamine significantly impacted analyte recovery. The optimum values were defined as 120 min, 10 mmol/L of NaOH, 150 μL, and 0%, respectively. Once optimized, validation parameters were 1-100 ng mL-1 as linear range, accuracy ±16.4%, precision >83%, 1 ng mL-1 as limit of quantitation, 0.1-0.75 ng mL-1 as limit of detection, matrix effect <20%, and recovery 20-106%. Additionally, EO purchased from different production batches were tested and achieved acceptable reproducibility. Data were in compliance with requirements set by internationally accepted validation guidelines and the applicability of the technique was proven using authentic samples.

SIGNIFICANCE

In this study, the use of an EO provided a solvent-free sample preparation technique suited to extract different classes of drugs of abuse from plasma samples, dismissing the use of hazardous organic solvents. The method also provided excellent sample clean-up, thus being a simple and efficient tool for toxicological applications that is in agreement with the principles of sustainable chemistry.

Bibliometric evaluation of Journal of Analytical Toxicology as a scholarly publication according to the Web-of-Science citation database

Soon approaching its 50th anniversary, Journal of Analytical Toxicology (JAT) is an international scholarly publication specializing in analytical and forensic aspects of toxicology. Science Citation Index (SCI) and Journal Citation Reports (JCR), both of which are part of the Web-of-Science (WOS) database, were used to make a bibliometric evaluation of JAT articles. Between 1977 (volume 1) and 2023 (volume 47), a total of  n = 4,785 items were published in JAT; the top-ten most highly cited articles and the most prolific authors were identified. Changes in the journal impact factor (JIF) were studied between 1997 and 2022, and this metric varied from a low of 1.24 (2006) to a high of 3.36 (2020).The most recent JIF (2022) dropped to 2.5 and the corresponding 5 year JIF was 2.6. JAT's most highly cited article (590 cites) was a working group (SWGTOX) report dealing with standard practices for the validation of analytical methods in forensic toxicology laboratories. JAT published 62 articles each of which were cited over 100 times and the H-index for JAT was 89. The most prolific author of JAT articles was credited with 119 items, the first in 1980 (volume 4) and the latest in 2023 (volume 47). JAT articles were cited 4,537 times in 2022 by all journals in the JCR database, although 520 of these were self-citations (11.5%). Bibliometric methods are increasingly used to evaluate the published work of individual scientists, university departments, entire universities and whole countries. Highly cited articles are considered more influential and authoritative compared with papers that are seldom or never cited.

Green analytical toxicology method for determination of synthetic cathinones in oral fluid samples by microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry

PURPOSE

We developed and validated a method for quantitative analysis of ten synthetic cathinones in oral fluid (OF) samples, using microextraction by packed sorbent (MEPS) for sample preparation followed by liquid chromatography‒tandem mass spectrometry (LC‒MS/MS).

METHOD

OF samples were collected with a Quantisal™ device and 200 µL was extracted using a C18 MEPS cartridge installed on a semi-automated pipette and then analyzed using LC‒M/SMS.

RESULTS

Linearity was achieved between 0.1 and 25 ng/mL, with a limit of detection (LOD) of 0.05 ng/mL and a limit of quantification (LOQ) of 0.1 ng/mL. Imprecision (% relative standard deviation) and bias (%) were better than 11.6% and 7.5%, respectively. The method had good specificity and selectivity against 9 different blank OF samples (from different donors) and 68 pharmaceutical and drugs of abuse with concentrations varying between 400 and 10,000 ng/mL. No evidence of carryover was observed. The analytes were stable after three freeze/thaw cycles and when kept in the autosampler (10 °C) for up to 24 h. The method was successfully applied to quantify 41 authentic positive samples. Methylone (mean 0.6 ng/mL, median 0.2 ng/mL), N-ethylpentylone (mean 16.7 ng/mL, median 0.35 ng/mL), eutylone (mean 39.1 ng/mL, median 3.6 ng/mL), mephedrone (mean 0.5 ng/mL, median 0.5 ng/mL), and 4-chloroethcathinone (8.1 ng/mL) were quantified in these samples.

CONCLUSION

MEPS was an efficient technique for Green Analytical Toxicology purposes, which required only 650 µL organic solvent and 200 µL sodium hydroxide, and the BIN cartridge had a lifespan of 100 sample extractions.

Recent advances in analysis of new psychoactive substances by means of liquid chromatography coupled with low-resolution tandem mass spectrometry

The number of methods for the analysis of new psychoactive substances (NPS) is continually increasing, and there is no indication that this trend will change in the near future. The constantly growing market of "designer drugs" makes it necessary to develop new methods of their analysis. The aim of this review is to present the multi-component methods of detection and identification of NPS using low-resolution tandem mass spectrometry coupled with liquid chromatography. For this purpose, 36 articles were selected by applying strictly defined search criteria. Due to the large differences in the matrices and physicochemical properties of the analytes, the described research methods are diverse. These differences are visible in sample preparation methods, chromatographic columns, mobile phases, gradients, or additives to mobile phases used. This work collects and organizes the existing information on the subject of NPS screening analysis methods and will be helpful to forensic scientists working on this topic.

Development and validation of a sensitive LC-MS-MS method to quantify psilocin in authentic oral fluid samples

Psilocin is an active substance and a dephosphorylated product of psilocybin formed after the ingestion of mushrooms. The low stability caused by the quick oxidation of this analyte requires sensitive methods for its determination in biological matrices. In this work, we described the development, optimization and validation of a method for the quantification of psilocin in authentic oral fluid samples by liquid chromatography-tandem mass spectrometry. Liquid-liquid extraction was performed using 100 µL of oral fluid samples collected with a Quantisal™ device and t-butyl methyl ether as the extraction solvent. The method showed acceptable performance, with limits of detection and quantification of 0.05 ng/mL, and the calibration model was achieved between 0.05 and 10 ng/mL. Bias and imprecision results were below -14.2% and 10.7%, respectively. Ionization suppression/enhancement was lower than -30.5%, and recovery was >54.5%. Dilution integrity bias was <14.4%. No endogenous and exogenous interferences were observed upon analyzing oral fluid from 10 different sources and 56 pharmaceuticals and drugs of abuse, respectively. No carryover was observed at 10 ng/mL. Psilocin was stable in oral fluid at -20°C, 4°C and 24°C up to 24, 72 and 24 h, respectively, with variations <17.7%. The analyte was not stable after three freeze/thaw cycles, with variations between -73% and -60%. This suggests the instability of psilocin in oral fluid samples, which requires timely analysis, as soon as possible after the collection. The analyte remained stable in processed samples in an autosampler (at 10°C) for up to 18 h. The method was successfully applied for the quantification of five authentic samples collected from volunteers attending parties and electronic music festivals. Psilocin concentrations ranged from 0.08 to 36.4 ng/mL. This is the first work to report psilocin concentrations in authentic oral fluid samples.

A new application of the switchable hydrophilicity solvent-based homogenous liquid-liquid microextraction to analyze synthetic cannabinoids in plasma by LC-MS/MS

Synthetic cannabinoids are still a growing trend among drug users and consist of a group of hundreds of highly potent compounds. To investigate the use of such substances, sample preparation of biological matrices is a crucial step prior to instrumental analysis. Although different efficient extraction techniques have been proposed for that aim, they usually do not fit eco-friendly guidelines that have been gaining popularity in recent years, such as Green Analytical Toxicology. This work uses describes for the first time the use of switchable hydrophilicity solvent-based homogenous liquid-liquid microextraction (SHS-HLLME) for synthetic cannabinoids. This is a green technique that replaces highly toxic organic reagents for switchable hydrophilicity solvents (SHS), substances that can be either water-miscible or immiscible depending on their protonation. Thus, by simply adjusting the pH of the system, these SHS can be used as extraction solvents. A full optimization study including type of SHS, volume of protonated SHS, volume of NaOH, salting-out effect, and extraction time was performed. The optimized procedure consisted of precipitating the proteins of 300 µL of plasma with 300 µL of acetonitrile followed by centrifugation; evaporation of the organic solvent under N2 stream; addition of 500 µL of the protonated DPA, DPA-HCl (6 M) (1:1, v/v); addition of 500 µL of NaOH (10 M); and finally centrifugation and evaporation. Validation results showed determination coefficients ≥ 0.99 for the 0.1-10 ng/mL linear range; 0.01-0.08 ng/mL as limit of detection; 0.1 ng/mL as limit of quantitation; accuracy and imprecision were within acceptable ranges; matrix effect, recovery, and process efficiency ranged from -55.6 to 185.9%, 36-56.7%, and 18.5-148.4%, respectively. The SHS-HLLME herein described was fully optimized providing satisfactory recoveries of 31 synthetic cannabinoids at low concentrations requiring only 300 µL of plasma. In addition, the validation results showed that the technique is a reliable eco-friendly alternative for clinical and toxicological analysis.

Review of analytical methods for screening and quantification of fentanyl analogs and novel synthetic opioids in biological specimens

Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC-MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010-2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC-MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation.

Simultaneous Determination and Stability Analysis of Ten New Psychoactive Substances including Synthetic Cathinones, Phenethylamines, and Ketamine Substitutes in Urine Using Liquid Chromatography-Tandem Mass Spectrometry

Knowing the stability of drugs is important to ensure accurate and reliable results of drug concentrations. This study evaluated the stability of ten new psychoactive substances (NPSs) in urine and methanol/water at different storage temperatures. Quantitative analyses were performed using liquid chromatography-tandem mass spectrometry. Three replicates of each storage condition were analyzed at day 0 and after 7, 14-, 30-, 60-, and 90 days with storage at +25°C, +4°C, and -20°C. For each analyte, the percent difference at each time interval from day 0 was calculated for each storage condition. Para-methoxyamphetamine (PMA), para-methoxymethamphetamine (PMMA), deschloroketamine (DCK), and 2-fluorodeschloroketamine (2-FDCK) were stable in urine, even when stored for 90-day periods at various temperatures. For synthetic cathinones, the concentrations declined over time at room temperature (+25°C) in urine but were relatively stable in methanol solvent with 0.1% formic acid. The significant degradation was found at +25°C, and the most excellent stability was shown by samples stored at -20°C. Phenethylamines (PMA and PMMA) and ketamine substitutes (DCK and 2-FDCK) were relatively more stable than synthetic cathinones (mephedrone, butylone, pentylone, ephylone, 4-MEAPP, and eutylone).

How to sample a seizure plant: the role of the visualization spatial distribution analysis of Lophophora williamsii as an example

Natural compounds in plants are often unevenly distributed, and determining the best sampling locations to obtain the most representative results is technically challenging. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) can provide the basis for formulating sampling guideline. For a succulent plant sample, ensuring the authenticity and in situ nature of the spatial distribution analysis results during MSI analysis also needs to be thoroughly considered. In this study, we developed a well-established and reliable MALDI-MSI method based on preservation methods, slice conditions, auxiliary matrices, and MALDI parameters to detect and visualize the spatial distribution of mescaline in situ in Lophophora williamsii. The MALDI-MSI results were validated using liquid chromatography-tandem mass spectrometry. Low-temperature storage at -80°C and drying of "bookmarks" were the appropriate storage methods for succulent plant samples and their flower samples, and cutting into 40 μm thick sections at -20°C using gelatin as the embedding medium is the appropriate sectioning method. The use of DCTB (trans-2-[3-(4-tert-butylphenyl)-2-methyl-2-propenylidene]malononitrile) as an auxiliary matrix and a laser intensity of 45 are favourable MALDI parameter conditions for mescaline analysis. The region of interest semi-quantitative analysis revealed that mescaline is concentrated in the epidermal tissues of L. williamsii as well as in the meristematic tissues of the crown. The study findings not only help to provide a basis for determining the best sampling locations for mescaline in L. williamsii, but they also provide a reference for the optimization of storage and preparation conditions for raw plant organs before MALDI detection.

Key Points

An accurate in situ MSI method for fresh water-rich succulent plants was obtained based on multi-parameter comparative experiments.Spatial imaging analysis of mescaline in Lophophora williamsii was performed using the above method.Based on the above results and previous results, a sampling proposal for forensic medicine practice is tentatively proposed.

Determination of synthetic hallucinogens in oral fluids by microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry

A fast and simple procedure based on microextraction by packed sorbent (MEPS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the simultaneous quantification of 28 synthetic hallucinogens in oral fluids, including lysergic acid diethylamide and substances from NBOMe, NBOH, NBF, 2C, and substituted amphetamine categories. Extraction conditions such as type of sorbent, sample pH, number of charge/discharge cycles, and elution volume were studied. Hallucinogenic compounds were extracted from oral fluid samples using C18 MEPS, loading with 100 μL sample (adjusted to pH 7) in 3 cycles, washing with 100 μL deionized water, and eluting with 50 μL methanol in 1 cycle, giving quantitative recoveries and no significant matrix effects. Limits of detection from 0.09 to 1.22 μg L^-1; recoveries from 80 to 129% performed in spiked oral fluid samples at 20, 50, and 100 μg L^-1; and high precision with relative standard deviations lower than 9% were obtained. The proposed methodology was demonstrated to be appropriate for the simple and sensitive determination of NBOMe derivates and other synthetic hallucinogenic substances in oral fluid samples.

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.

Analysis of 2,5-dimethoxy-amphetamines and 2,5-dimethoxy-phenethylamines aiming their determination in biological matrices: a review

PURPOSE

The present review aims to provide an overview of methods for the quantification of 2,5-dimethoxy-amphetamines and -phenethylamines in different biological matrices, both traditional and alternative ones.

METHODS

A complete literature search was carried out with PubMed, Scopus and the World Wide Web using relevant keywords, e.g., designer drugs, amphetamines, phenethylamines, and biological matrices.

RESULTS

Synthetic phenethylamines represent one of the largest classes of "designer drugs", obtained through chemical structure modifications of psychoactive substances to increase their pharmacological activities. This practice is also favored by the fact that every new synthetic compound is not considered illegal by existing legislation. Generally, in a toxicological laboratory, the first monitoring of drugs of abuse is made by rapid screening tests that sometimes can occur in false positive or false negative results. To reduce evaluation errors, it is mandatory to submit the positive samples to confirmatory methods, such as gas chromatography or liquid chromatography combined to mass spectrometry, for a more specific qualitative and quantitative analysis.

CONCLUSIONS

This review highlights the great need for updated comprehensive analytical methods, particularly when analyzing biological matrices, both traditional and alternative ones, for the search of newly emerging designer drugs.

New Psychoactive Substances: Which Biological Matrix Is the Best for Clinical Toxicology Screening?

BACKGROUND

Every year, more new psychoactive substances (NPSs) emerge in the market of the drugs of abuse. NPSs belong to various chemical classes, such as synthetic cannabinoids, phenethylamines, opioids, and benzodiazepines. The detection of NPSs intake using different types of biological matrices is challenging for clinical toxicologists because of their structural diversity and the lack of information on their toxicokinetics, including their metabolic fate.

METHODS

PubMed-listed articles reporting mass spectrometry-based bioanalytical approaches for NPSs detection published during the past 5 years were identified and discussed. Furthermore, the pros and cons of using common biological matrices in clinical toxicology (CT) settings to screen for NPSs are highlighted in this review article.

RESULTS

Twenty-six articles presenting multianalyte screening methods for use in the field of CT were considered. The advantages and disadvantages of different biological matrices are discussed with a particular view of the different analytical tasks in CT, especially emergency toxicology. Finally, an outlook introduces the emerging trends in biosamples used in CT, such as the exhaled breath.

CONCLUSIONS

Blood and urine represent the most common biological matrices used in a CT setting; however, reports concerning NPSs detection in alternative matrices are also available. Noteworthy, the selection of the biological matrix must depend on the clinician's enquiry because the individual advantages and disadvantages must be considered.

Development and validation of the UPLC-MS method for simultaneous determination of six new psychoactive substances

The combined abuse of benzodiazepines and antipsychotics has become a global problem, and to develop a highly sensitive and selective method for monitoring of benzodiazepine hypnotics and antipsychotics is urgently necessary. In this work, we established a rapid method for the simultaneous determination of benzodiazepines (diazepam, alprazolam, triazolam, and estazolam) and antipsychotic drugs (clozapine, and chlorpromazine) based on ultra performance liquid chromatography-mass spectrometry (UPLC-MS). The accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), specificity, matrix effect and carry-over effect were verified in detail. The results of the recovery and repeat experiments proved that the proposed UPLC-MS method possessed very satisfactory accuracy and precision. The LOD and LOQ of the six psychoactive substances were as low as 0.001-0.005 and 0.005-0.01 μg L-1, respectively. The proposed method was employed to analyze urine samples which were pretreated with a protein precipitation process. The potential influences of precipitants on the analysis results were evaluated statistically, and 0.1% formic acid/acetonitrile/water was selected as the optimum precipitation agent. The detection of the targets was free from matrix and carryover effects.

In Vivo Bio-Activation of JWH-175 to JWH-018: Pharmacodynamic and Pharmacokinetic Studies in Mice

3-(1-Naphthalenylmethyl)-1-pentyl-1H-indole (JWH-175) is a synthetic cannabinoid illegally marketed for its psychoactive cannabis-like effects. This study aimed to investigate and compare in vitro and in vivo pharmacodynamic activity of JWH-175 with that of 1-naphthalenyl (1-pentyl-1H-indol-3-yl)-methanone (JWH-018), as well as evaluate the in vitro (human liver microsomes) and in vivo (urine and plasma of CD-1 male mice) metabolic profile of JWH-175. In vitro binding studies showed that JWH-175 is a cannabinoid receptor agonist less potent than JWH-018 on mouse and human CB1 and CB2 receptors. In agreement with in vitro data, JWH-175 reduced the fESPS in brain hippocampal slices of mice less effectively than JWH-018. Similarly, in vivo behavioral studies showed that JWH-175 impaired sensorimotor responses, reduced breath rate and motor activity, and increased pain threshold to mechanical stimuli less potently than JWH-018. Metabolic studies demonstrated that JWH-175 is rapidly bioactivated to JWH-018 in mice blood, suggesting that in vivo effects of JWH-175 are also due to JWH-018 formation. The pharmaco-toxicological profile of JWH-175 was characterized for the first time, proving its in vivo bio-activation to the more potent agonist JWH-018. Thus, it highlighted the great importance of investigating the in vivo metabolism of synthetic cannabinoids for both clinical toxicology and forensic purposes.

High-sensitivity method for the determination of LSD and 2-oxo-3-hydroxy-LSD in oral fluid by liquid chromatography‒tandem mass spectrometry

PURPOSE

We have developed and validated a high-sensitivity method to quantify lysergic acid diethylamide (LSD) and 2-oxo-3-hydroxy-LSD (OH-LSD) in oral fluid samples using liquid-liquid extraction and liquid chromatography-tandem mass spectrometry (LC‒MS/MS). The method was applied to the quantification of both substances in 42 authentic oral fluid samples.

METHODS

A liquid-liquid extraction was performed using 500 µL each of samples (oral fluid samples collected using Quantisal™ device) and dichloromethane/isopropanol mixture (1:1, v/v). Enzymatic hydrolysis was evaluated to cleave glucuronide metabolites.

RESULTS

The limit of quantification was 0.01 ng/mL for both LSD and OH-LSD. The linearity was assessed between 0.01 and 5 ng/mL. Imprecision and bias were not higher than 10.2% for both analytes. Extraction recovery was higher than 69%. The analytes were stable in the autosampler at 10 °C for 24 h, and up to 30 days at 4 and -20 °C. The method was applied to the analysis of 42 oral fluid samples. LSD was detected in all samples (concentrations between 0.02 and 175 ng/mL), and OH-LSD was detected in 20 samples (concentrations between 0.01 and 1.53 ng/mL).

CONCLUSIONS

A high-sensitive method was fully validated and applied to authentic samples. To our knowledge, this is the first work to report concentrations of LSD and OH-LSD in authentic oral fluid 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.

Oral fluid analysis to monitor recent exposure to synthetic cannabinoids in a high-risk subpopulation

Among novel psychoactive substances, synthetic cannabinoid receptor agonists (SCRA) seem to have the widest diffusion in the population with no limitation to any particular demographic group. Information on drug consumption relies mostly on anonymized surveys and less on clinical or analytical data; notwithstanding, the huge efforts constantly made to enroll subjects to gather epidemiological data. In the present study, we collected 66 oral fluid samples from volunteers in a drug rehabilitation center in 2019 and early 2020. A liquid chromatography-mass spectrometry method previously developed and validated by our Unit was applied to detect SCRA (n = 10) in oral fluid. Results proved the presence of synthetic cannabinoids at a positivity rate of almost 20%, with detection frequency HU211(5/13) > UR144/JWH122 (3/13) > JWH019/JWH081/AM2201 (1/13). Concentrations were in the range < LOQ -0.36 ng/ml. Synthetic cannabinoids consumption had not been declared by any volunteer. This study enabled for the unprecedent detection of synthetic cannabinoids use in the territory of Parma (Italy) in a high-risk subpopulation. The identified SCRA proved the persistence into the market of the "first-generation" JWH family into the Italian territory and the marketing of relatively new ones (AM-2201). Public health consequences represented by NPS consumption are still scarce; therefore, further studies are needed to understand the real diffusion in the population.

Rapid Extraction and Qualitative Screening of 30 Drugs in Oral Fluid at Concentrations Recommended for the Investigation of DUID Cases

A rapid, simple extraction method followed by qualitative screening using liquid chromatography-tandem mass spectrometry (LC-MS-MS) for drugs in oral fluid is presented. The decision points were selected to be at, or lower, than those recommended as Tier I compounds by the National Safety Council's Alcohol, Drugs, and Impairment Division for toxicological investigation of driving under the influence of drugs cases (DUID) and were also at, or lower, than those recommended by Substance Abuse and Mental Health Service Administration (SAMHSA) and the Department of Transportation (DOT) for Federal workplace drug testing programs. The method included 30 drugs: delta-9-tetrahydrocannabinol (THC), amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), cocaine, benzoylecgonine, carisoprodol, meprobamate, zolpidem, alprazolam, clonazepam, 7-aminoclonazepam, diazepam, nordiazepam, lorazepam, oxazepam, temazepam, codeine, morphine, 6-acetylmorphine, buprenorphine, fentanyl, hydrocodone, hydromorphone, oxycodone, oxymorphone, methadone, tramadol, and phencyclidine. Phencyclidine was included because it is in the Federal workplace program even though it is considered a Tier II drug for DUID cases. A liquid-liquid extraction method using isopropanol, hexane, and ethyl acetate to extract drugs from the oral fluid-buffer mix collected in a Quantisal™ device, followed by LC-MS-MS screening was developed and validated according to ANSI/ASB 2019 Standard Practices for Method Validation in Forensic Toxicology. Interference studies, limit of detection, precision at the decision point, ionization suppression/enhancement and processed sample stability were determined for each drug. The method was successfully applied to proficiency specimens and routine samples received into the laboratory.

Detection of the Synthetic Cannabinoids AB-CHMINACA, ADB-CHMINACA, MDMB-CHMICA, and 5F-MDMB-PINACA in Biological Matrices: A Systematic Review

Simple Summary

Synthetic cannabinoids were originally developed for scientific research and potential therapeutic agents. However, clandestine laboratories synthesize them and circumvent legal barriers by falsely marketing them as incense or herbal products. They have serious adverse effects, and new derivatives are continuously found in the market, making their detection difficult due to the lack of comparative standards. Human matrices are used to identify the type of synthetic cannabinoid and the time of its consumption. This review discusses the use of hair, oral fluid, blood, and urine in the detection and quantification of some of the major synthetic cannabinoids. Based on the results, some recommendations can be followed, for example, the use of hair to detect chronic and retrospective consumption (although sensitive to external contamination) and oral fluid or blood for the simultaneous detection of the parent compounds and their metabolites. If longer detection times than blood or oral fluid are needed, urine is the matrix of choice, although its pH may intervene in the analysis. This work highlights the use of new techniques, such as high-resolution mass spectrometry, to avoid the use of previous standards and to monitor new trends in the drug market.

Abstract

New synthetic cannabinoids (SCs) are emerging rapidly and continuously. Biological matrices are key for their precise detection to link toxicity and symptoms to each compound and concentration and ascertain consumption trends. The objective of this study was to determine the best human biological matrices to detect the risk-assessed compounds provided by The European Monitoring Centre for Drugs and Drug Addiction: AB-CHMINACA, ADB-CHMNACA, MDMB-CHMICA, and 5F-MDMB-PINACA. We carried out a systematic review covering 2015 up to the present date, including original articles assessing detection in antemortem human biological matrices with detailed validation information of the technique. In oral fluid and blood, SC parent compounds were found in oral fluid and blood at low concentrations and usually with other substances; thus, the correlation between SCs concentrations and severity of symptoms could rarely be established. When hair is used as the biological matrix, there are difficulties in excluding passive contamination when evaluating chronic consumption. Detection of metabolites in urine is complex because it requires prior identification studies. LC-MS/MS assays were the most widely used approaches for the selective identification of SCs, although the lack of standard references and the need for revalidation with the continuous emergence of new SCs are limiting factors of this technique. A potential solution is high-resolution mass spectrometry screening, which allows for non-targeted detection and retrospective data interrogation.

Online SPE UPLC-MS/MS method for the simultaneous determination of 33 psychoactive drugs from swab-collected human oral fluid samples

Oral fluid is easy and safe to collect and allows the detection of drugs of abuse after local exposure by oral, smoked, and/or inhaled intake, or systemic exposure. A routine online solid-phase extraction UPLC-MS/MS method was developed for the simultaneous determination of 33 psychoactive drugs in oral fluid. The selected drugs were fourteen fentanyl analogs and nineteen other abused psychoactive compounds, including classical narcotics, which were analyzed in a run of 10 min. Limits of detection and of quantification ranged from 0.02 to 1 ng/mL and from 0.02 to 5 ng/mL depending on the analyte, respectively. Matrix effect was in the range - 17 to + 15.7% for all analytes having a deuterated analog. Accuracy ranged from 82.7 to 113.4% and precision CV was at worst of 18.6%. Carryover was below 0.8% for all analytes. Recovery from FLOQSwabs™ showed high variability between analytes with THC, D2FF, 4-ANPP, ocfentanil, and valerylfentanyl being recovered below 40%. A stability study performed over 2 weeks on collecting devices loaded with artificial oral fluid showed huge variation between analytes with morphine, BZE, and norfentanyl being the more stable. Storage at 4 °C allowed drug detection for 1 week except for THC and remifentanil. The method was successfully applied to the detection of abused psychoactive compounds in oral fluid samples from 6 patients admitted to an addiction department.

Analysis of drugs including illicit and new psychoactive substances in oral fluids by gas chromatography-drift tube ion mobility spectrometry

In this study, a gas chromatograph (GC) has been coupled to a drift tube ion mobility spectrometer (IMS) in order to develop an analytical procedure for the determination of psychoactive substances in oral fluids. Working parameters, including the GC-IMS interface ones, were adjusted in order to obtain sensitive and robust signals. A volume of 500 μL of oral fluid was extracted with 250 μL chloroform and, after centrifugation, were injected into the GC-IMS system. Amphetamine, methylone, α-PVP, ketamine, lidocaine, MPHP, cocaine, THJ-2201, and 5F-ADB were employed as model compounds, providing limits of detection from 6 to 15 μg L^-1 and recoveries from 70 to 115% for field oral fluids spiked with target analytes at 250, 500, and 600 μg L^-1. Moreover, two oral fluid certified reference materials were analysed by the proposed GC-IMS based methodology with obtained relative percentage errors lower than 8.4%, being the proposed GC-IMS procedure a reliable, selective, and sensitive technique for the determination of psychoactive substances in oral fluids.

Determination of synthetic opioids in oral fluid samples using fabric phase sorptive extraction and gas chromatography-mass spectrometry

New psychoactive substances (NPS) continue to emerge in the drug market every year, becoming a global threat to public health and safety. These compounds are mostly synthetic cannabinoids and designer cathinones. However, synthetic opioids have appeared on the recreational drug markets in recent years, particularly fentanyl and its derivatives ("fentanyls"). Fentanyl and its analogs are related to harmful intoxications and an increase in opioid-related mortality in many countries, such as in the United States and Europe in the last years. Taking the drug related global crisis into consideration, this work developed and validated an effective and sensitive method based on fabric phase sorptive extraction (FPSE) followed by gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of 11 fentanyl analogs in oral fluid samples. The extraction was carried out using a sol-gel Carbowax 20 M sorbent immobilized on 100% cellulose fabric substrate and using ethyl acetate as the desorption solvent. The limits of detection (LODs) and quantification (LOQs) ranged from 1 to 15 ng mL^-1 and 5 to 50 ng mL^-1, respectively. Intra-day and inter-day precision were found within 8.2% and 8.6%, respectively, while accuracy ranged from -5.5 to 9.1%, in accordance with the established criteria. The absolute recovery values were in the range of 94.5%-109.1%. The validated method demonstrated its great potential to detect and quantify fentanyl analogs in possible forensic work and off-site analysis in road traffic cases.

Rethinking Drug Analysis in Healthcare: High-Throughput Analysis of 71 Drugs of Abuse in Oral Fluid using Ion Mobility - High Resolution Mass Spectrometry

We have identified a clinical need for a sensitive, specific, flexible, comprehensive, and affordable analytical technology to efficiently detect polydrug use. In addition, the current standard practise of surveilled urine sampling is uncomfortable for the patient, hence more patient-friendly sample collection methods are requested. To fill these needs, we have developed and validated a high-throughput liquid chromatography - high resolution mass spectrometry (LC-HRMS) method for analysis of DoA in oral fluid (OF). The method covers a panel of 71 substances including traditional drugs of abuse (DoA), prescription narcotics and new psychoactive substances (NPS), with a guaranteed limit of identification of <3 µg/L for 87% of the analytes. Method validation showed high accuracy (>99.7%), sensitivity (>99.7%) and specificity (100%). Most analytes had a high process efficiency during the salting out liquid-liquid extraction (SALLE) workup and no or only a minor matrix effect during the analysis. We have implemented this method in clinical routine, and present data from 18,579 OF samples collected during routine patient treatment in mainly psychiatric and addiction clinics in West Sweden between September 2020 and June 2021. 71% of the samples were positive and a total of 41,472 DoA findings were detected. Amphetamine (27%), buprenorphine (25%), nordiazepam (18%) and alprazolam (16%) were most prevalent. NPS were detected in 189 samples (1.0%). Occurrence of polydrug use was common, 34% of the positive samples contained three analytes or more and 12% six or more. To the best of our knowledge, this is the first method for comprehensive analysis of DoA in OF using HRMS and the largest dataset published on detection of DoA in OF. With the current complex and variable drug use pattern, this broad, cost-effective and reliable method has largely replaced immunoassay screening in urine in our laboratory.

Prevalence of new psychoactive substances (NPS) in Brazil based on oral fluid analysis of samples collected at electronic music festivals and parties

BACKGROUND

New psychoactive substances (NPS) use is a worldwide public health issue. Knowing the prevalence of NPS guides public health and legal policies to address the problem. The objective of this study was to identify NPS in Brazil through the analysis of oral fluid (OF) samples collected at parties and electronic music festivals.

METHODS

Anonymous questionnaires and oral fluid samples were collected from volunteers (≥18 years) who reported the consumption of at least one illicit psychoactive substance in the last 24 h. Oral fluid sample collections occurred at eleven parties and two electronic music festivals over 16 months (2018-2020). Questionnaire answers were matched to oral fluid toxicological results.

RESULTS

Of 462 oral fluid samples, 39.2 % were positive for at least one NPS by liquid chromatography‒tandem mass spectrometry (LC-MS/MS). The most prevalent NPS was ketamine (29.4 %), followed by methylone (6.1 %) and N-ethylpentylone (4.1 %); however, MDMA was the most commonly identified (88.5 %) illicit psychoactive substance. More than one drug was identified in 79.9 % of samples, with two (34.2 %) and three (23.4 %) substances most commonly observed. Only 5 % of volunteers reported recent NPS consumption.

CONCLUSION

MDMA is still the most common party and electronic music festival drug, although NPS were identified in more than one-third of oral fluid samples.

Simultaneous Quantification of 25 Fentanyl Derivatives and Metabolites in Oral Fluid by Means of Microextraction on Packed Sorbent and LC-HRMS/MS Analysis

Fentanyl and fentalogs’ intake as drugs of abuse is experiencing a great increase in recent years. For this reason, there are more and more cases in which it is important to recognize and quantify these molecules and related metabolites in biological matrices. Oral fluid (OF) is often used to find out if a subject has recently used a psychoactive substance and if, therefore, the person is still under the effect of psychotropics. Given its difficulty in handling, good sample preparation and the development of instrumental methods for analysis are essential. In this work, an analytical method is proposed for the simultaneous determination of 25 analytes, including fentanyl, several derivatives and metabolites. OF was collected by means of passive drool; sample pretreatment was developed in order to be fast, simple and possibly semi-automated by exploiting microextraction on packed sorbent (MEPS). The analysis was performed by means of LC–HRMS/MS obtaining good identification and quantification of all the analytes in less than 10 min. The proposed method was fully validated according to the Scientific Working Group for Forensic Toxicology (SWGTOX) international guidelines. Good results were obtained in terms of recoveries, matrix effect and sensitivity, showing that this method could represent a useful tool in forensic toxicology. The presented method was successfully applied to the analysis of proficiency test samples.

Simultaneous determination of 137 drugs of abuse, new psychoactive substances, and novel synthetic opioids in meconium by UHPLC-QTOF

New psychoactive substances (NPS) have been introduced into the market in recent years, with new analytes reported every year. The use of these substances in women can occur at any stage of life, even in the childbearing age. Drug use during pregnancy presents significant risks for the mother and the fetus, so it is important to have tools that allow to detect prenatal exposure to these substances of abuse. Therefore, an analytical method for the determination of 137 NPS and other drugs of abuse in meconium by UHPLC-QTOF was developed and validated for semi-quantitative purpose. Linearity range, limit of detection (LOD), precision, matrix effect, selectivity, and specificity were evaluated. For all analytes, the calibration curves were studied in the ranges between 2, 10, or 50 ng/g and 750 or 1000 ng/g, (depending on the analyte) and the LOD ranged between 0.04 and 2.4 ng/g. The method was applied to 30 meconium specimens from cases in which fentanyl had been administered as epidural anesthesia at the time of delivery or cases in which the maternal hair was positive to other drug of abuse. Four meconium samples tested positive for fentanyl (range concentration = 440-750 ng/g) and two samples tested positive to acetylfentanyl (range concentration = 190-1400 ng/g).

Quantification of fentanyl analogs in oral fluid using LC-QTOF-MS

Oral fluid is a valuable alternative matrix for forensic toxicologists due to ease of observed collection, limited biohazardous exposure, and indications of recent drug use. Limited information is available for fentanyl analog prevalence, interpretation, or analysis in oral fluid. With increasing numbers of fentanyl-related driving under the influence of drug (DUID) cases appearing in the United States, the development of detection methods is critical. The purpose of the present study was to develop and validate a quantitative method for fentanyl analogs in oral fluid (collected via Quantisal™) using liquid chromatography-quadrupole-time-of-flight-mass spectrometry (LC-QTOF-MS). Validation resulted in limits of detection and quantification ranging from 0.5 to 1 ng/mL. Established linear range was 1-100 ng/mL for all analytes, except acetyl fentanyl at 0.5-100 ng/mL (R²  > 0.994). Within- and between-run precision and bias were considered acceptable with maximum values of ±15.2%CV and ±14.1%, respectively. Matrix effects exhibited ionization enhancement for all analytes with intensified enhancement at a low concentration (9.3-47.4%). No interferences or carryover was observed. Fentanyl analogs were stable in processed extracts stored in the autosampler (4^⁰ C) for 48h. The validated method was used to quantify fentanyl analogs in authentic oral fluid samples (n=17) from probationers/parolees. Fentanyl and 4-ANPP concentrations were 1.0-104.5 ng/mL and 1.2-5.7 ng/mL, respectively.

Impact of Quantisal® Oral Fluid Collection Device on Drug Stability

The stability of drugs can affect drug tests and interpretations. A comprehensive study to verify drug stability in Quantisal® oral fluid (OF) collection device was undertaken in accordance with Australian standard, AS/NZS 4760:2019 (SAI-Global, 2019). The evaluation was performed for the following drugs: (±) amphetamine, (±) methylamphetamine, (±) 3,4-methylenedioxymethylamphetamine (MDMA), (−)Δ9-tetrahydrocannabinol (THC), cocaine, benzoylecgonine, morphine, codeine, and oxycodone. Stability was assessed at four different storage temperatures over seven time points at ±50% cut-off concentrations (Appendix A, Para A4-4.1, AS/NZS 4760:2019) (SAI-Global, 2019). All drugs were found to be significantly more stable at 4 and –20°C, with stability spanning at least 14 days with percentage change within ±20% from the cut-off concentrations (SAI-Global, 2019). In addition, we report a variation trend with cocaine and benzoylecgonine at elevated temperatures, suggesting hydrolytic decomposition of cocaine and a concomitant increase in benzoylecgonine quantitative values. We confirm the cross-talk by showing that the percentage change in the profile of average cocaine-benzoylecgonine measurement is within the acceptance concentration range of ±20%. This finding highlights the importance of precaution during storage and careful considerations during subsequent interpretation of liquid chromatography-mass spectrometry (LCMS) measurements.

Determination of synthetic cannabinoids in randomly urine samples collected from probationers in Turkey

Synthetic cannabinoids are a significant public health and safety problem that complicates drug tests with their ever-changing structures in our country and worldwide. The fact that most synthetic cannabinoids cannot be detected in biological samples by routine drug of abuse screening tests also causes an increase in the use of these substances in return. In this study, 500 urine samples of randomly selected probationers, analyzed with an enzymatic immunoassay test at Ege University Institute of Drug Addiction, Toxicology and Pharmaceutical Sciences (BATI) and tested negative, were then selected for retrospective analysis. Synthetic cannabinoids and their metabolites were quantitatively scanned in the collected urine samples via the liquid-liquid extraction method with the LC-MS/MS. Of the 500 studied urine samples, 108 (21.6%) were positive for 20 synthetic cannabinoids and their metabolites. The two most detected synthetic cannabinoids were 5F-NPB-22 (58%) and (S)-AB-FUBINACA (36%), and their mean concentrations were 72.94 ± 47.51 ng/mL and 5.84 ± 14.7 ng/mL, respectively. These results were also compared with national statistics from the general population. It resulted that immunoassay screening tests used in this study were insufficient, and urine samples should be studied in clinical and forensic cases with a validated chromatographic method.

Surveillance by oral fluid of drugs subject to misuse among individuals under arrest

Background: Between 1988 and 2013 the U.S. government conducted surveillance of national drug misuse use trends by collecting voluntary urine specimens from individuals under arrest in major counties. It was discontinued for financial reasons. The program was the only national survey that used a bioassay to measure drug use. Other national drug surveys continue to be based entirely on self-reports of drug use.Objective: Given the current opioid and incipient methamphetamine epidemics, this study aimed to demonstrate the feasibility of surveilling drugs subject to misuse among individuals under arrest using oral fluid collected anonymously by jail staff in one U.S. county. This method has never been previously employed with an offender population.Methods: The subjects were adults arrested for any reason and booked in one Midwest county jail in the U.S. between July 2019 - January 2020 (N = 196; 145 males). Oral fluid specimens were provided for research purposes voluntarily and anonymously.Results: 79% of individuals approached consented to participation. The most frequently detected drugs were cannabis (53%), methamphetamine (27%), cocaine (9%) and opioids (11%). Further, 74% tested positive for at least one drug; 36% tested positive for at least one illegal drug, 10% tested positive for at least one possibly illegal drug, and 54% tested positive for at least one legal drug (predominantly cannabis). (Tests for nicotine and ethanol were not included.)Conclusion: The feasibility of collecting oral fluid from individuals under arrest in a jail setting to measure the prevalence of drugs subject to misuse was demonstrated.

Quantification of amphetamine and derivatives in oral fluid by dispersive liquid-liquid microextraction and liquid chromatography-tandem mass spectrometry

The abuse of stimulants such as amphetamine, methamphetamine, ecstasy (MDMA), and their analogues (MDEA and MDA) has been increasing considerably worldwide since 2009. In this work, an analytical method using dispersive liquid-liquid microextraction (DLLME) to determine amphetamine and derivatives in oral fluid samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated. Linearity was achieved between 20 to 5000 ng/mL (r>0.992, 1/x² weighted linear regression), with a limit of quantification (LOQ) of 20 ng/mL. Imprecision (%relative standard deviation) and bias (%) were not higher than 9.1 and -12.3%, respectively. The matrix effect was lower than 14.6%, with no carryover observed up to 5000 ng/mL and no interference with 10 different oral fluid matrix sources and against 14 pharmaceuticals and other common drugs of abuse. MDMA, MDA, and MDEA in processed samples were stable up to 24 h at autosampler (10°C); and amphetamine and methamphetamine up to 18 h. The developed method was successfully applied to authentic oral fluid analyses (n = 140). The proposed method is an example of the Green Analytical Toxicology, since it reduces both the amount of solvent required in samples preparation and the quantity of solvents and reagents used in analytical-instrumental stage, as well as requires a minimal sample volume, being a cheaper, quicker and more ecological alternative to conventional methods. Obtained results showed that DLLME extraction combined with LC-MS/MS is a fast and simple method to quantify amphetamine derivatives in oral fluid samples.

The prevalence of liquid chromatography-tandem mass spectrometry confirmed paediatric poisoning at Red Cross War Memorial Children's Hospital, Cape Town, South Africa

Background

Paediatric poisoning is a common presentation to emergency departments worldwide. There is a paucity of data on the role of liquid chromatography-tandem mass spectrometry (LC-MS/MS), in the management of paediatric poisoning in low-and middle-income countries (LMICs). In high-income countries, most studies are retrospective, and few include children.

Objective

The study describes the prevalence of liquid chromatography-tandem mass spectrometry confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa.

Methods

Children admitted with suspected poisoning between 1 January 2017 and 31 December 2017, were recruited. All patients had a urine and/or blood sample sent for LC-MS/MS toxicology. Data collected included demographic data, clinical features, investigations, management, outcome and social interventions.

Results

One hundred fifty-two children, with median age of 39 (IQR 25–61) months were enrolled of which 128 (84%) were poisoning cases. Of the 128 poisoning cases, 88 (69%) presented with a history of ingesting a known substance, 16 (12%) an unknown substance and 24 (19%) were cases of occult poisoning. LC-MS/MS was able to identify a substance in 92% of the cases of occult poisoning. In those who had presented with a seemingly known substance, LC-MS/MS found a different substance in 15 cases. LC-MS/MS was also able to detect multiple drugs in 40 patients. Of the poisoning cases, six (5%) cases were attempted homicide cases and 5 (4%) cases were attempted suicide cases. No children died. Individualized social interventions were instituted in poisoning cases. Emergency placement safety reasons was required in 6 children.

Conclusion

When the limitations are known, LC-MS/MS is useful in identifying cases of occult poisoning, identifying patients who have ingested multiple substances and/or an unknown substance and when targeted towards child protection. As LC-MS/MS is an expensive test, it should be used judiciously in LMICs.

Development and validation of quantitative analytical method for 50 drugs of antidepressants, benzodiazepines and opioids in oral fluid samples by liquid chromatography–tandem mass spectrometry

Purpose

We developed and validated a method for quantitative analysis of 50 psychoactive substances and metabolites (antidepressants, benzodiazepines and opioids) in oral fluid samples using simple liquid–liquid extraction procedure followed by liquid chromatography–tandem mass spectrometry (LC–MS/MS).

Method

Oral fluid samples were collected using Quantisal™ device and extracted by liquid–liquid extraction with 1.0 mL of methyl tert-butyl ether and then analyzed using LC–MS/MS.

Results

The method attended method validation criteria, with limits of quantification as low as 0.5 and 1.0 ng/mL, and linearity between 0.5–50.0 ng/mL for antidepressants, 0.5–25.0 ng/mL for benzodiazepines and 1.0–50.0 ng/mL to opioids. During method validation, bias and imprecision values were not greater than 16 and 20%, respectively. Ionization suppression/enhancement bias results were not greater than 25%. No evidence of carryover was observed. Sample stability studies showed that almost all analytes were stable at 25 °C for 3 days and at 4 °C for 7 days. Freeze–thaw cycles stability showed that most antidepressants and opioids were stable under these conditions. Autosampler stability study showed that all analytes were stable for 24 h, except for nitrazepam and 7-aminoclonazepam. Thirty-eight authentic oral fluid samples were analyzed; 36.8% of the samples were positive for 2 drugs. Citalopram was the most common drug found, followed by venlafaxine.

Conclusions

The method was validated according to international recommendations for the 50 analytes, showing low limits of quantification, good imprecision and bias values, using simple liquid–liquid extraction, and was successfully applied to authentic oral fluid samples analysis.