Metabolic Stability and Metabolite Identification of N-Ethyl Pentedrone Using Rat, Mouse and Human Liver Microsomes.

New Psychoactive Substances (NPSs) are defined as a group of substances produced from molecular modifications of traditional drugs. These molecules represent a public health problem since information about their metabolites and toxicity is poorly understood. N-ethyl pentedrone (NEP) is an NPS that was identified in the illicit market for the first time in the mid-2010s, with four intoxication cases later described in the literature. This study aims to evaluate the metabolic stability of NEP as well as to identify its metabolites using three liver microsomes models. To investigate metabolic stability, NEP was incubated with rat (RLM), mouse (MLM) and human (HLM) liver microsomes and its concentration over time evaluated by liquid chromatography-mass spectrometry. For metabolite identification, the same procedure was employed, but the samples were analyzed by liquid chromatography-high resolution mass spectrometry. Different metabolism profiles were observed depending on the model employed and kinetic parameters were determined. The in vitro NEP elimination half-lives (t1/2) were 12.1, 187 and 770 min for the rat, mouse and human models, respectively. Additionally, in vitro intrinsic clearances (Cl int, in vitro) were 229 for rat, 14.8 for mouse, and 3.6 µL/min/mg in the human model, and in vivo intrinsic clearances (Cl int, in vivo) 128, 58.3, and 3.7 mL/min/kg, respectively. The HLM model had the lowest rate of metabolism when compared to RLM and MLM. Also, twelve NEP metabolites were identified from all models, but at different rates of production.

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.

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.

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.

In vitro metabolism of the new antifungal dapaconazole using liver microsomes.

Dapaconazole is a new antifungal imidazole that has been shown a high efficacy against several pathogenic fungi. This study aimed to investigate the interspecies variation in the in vitro metabolic profiles and in vivo hepatic clearance (CLH,in vivo) prediction of dapaconazole using liver microsomes from male Sprague Dawley rat, male Beagle dog and mixed gender human using a liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) method. In addition, the produced metabolites were identified by ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometer (UHPLC-QTOF-MS/MS). The microsomal protein concentration of 0.1 mg/mL and the incubation time of 10 min were employed for the kinetics determination, resulting in a sigmoidal kinetic profile for all species evaluated. The predicted CLH,in vivo was 6.5, 11.6 and 7.5 mL/min/kg for human, rat and dog, respectively. Furthermore, five metabolized products were identified. These findings provide preliminary information for understanding dapaconazole metabolism and the interspecies differences in catalytic behaviours, supporting the choice of a suitable laboratory animal for future pharmacokinetics and metabolism studies.

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.

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.

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.

Kinetic profile of N,N-dimethyltryptamine and ß-carbolines in saliva and serum after oral administration of ayahuasca in a religious context.

Ayahuasca is a beverage obtained from Banisteriopsis caapi plus Psychotria viridis. B. caapi contains the ß-carbolines harmine, harmaline, and tetrahydroharmine that are monoamine oxidase inhibitors and P. viridis contains N,N-dimethyltryptamine (DMT) that is responsible for the visionary effects of the beverage. Ayahuasca use is becoming a global phenomenon, and the recreational use of DMT and similar alkaloids has also increased in recent years; such uncontrolled use can lead to severe intoxications. In this investigation, liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to study the kinetics of alkaloids over a 24 h period in saliva and serum of 14 volunteers who consumed ayahuasca twice a month in a religious context. We compared the area under the curve (AUC), maximum concentration (Cmax ), time to reach Cmax (Tmax ), mean residence time (MRT), and half-life (t1/2 ), as well as the serum/saliva ratios of these parameters. DMT and ß-carboline concentrations (Cmax ) and AUC were higher in saliva than in serum and the MRT was 1.5-3.0 times higher in serum. A generalized estimation equations (GEEs) model suggested that serum concentrations could be predicted by saliva concentrations, despite large individual variability in the saliva and serum alkaloid concentrations. The possibility of using saliva as a biological matrix to detect DMT, ß-carbolines, and their derivatives is very interesting because it allows fast noninvasive sample collection and could be useful for detecting similar alkaloids used recreationally that have considerable potential for intoxication.

Screening of 104 New Psychoactive Substances (NPS) and Other Drugs of Abuse in Oral Fluid by LC-MS-MS.

New psychoactive substances (NPS) are a major public health problem, primarily due to the increased number of acute poisoning cases. Detection of these substances is a challenge. The aim of this research was to develop and validate a sensitive screening method for 104 drugs of abuse, including synthetic cannabinoids, synthetic cathinones, fentanyl analogues, phenethylamines and other abused psychoactive compounds (i.e., THC, MDMA, LSD and their metabolites) in oral fluid by liquid chromatography-tandem mass spectrometry (LC-MS-MS). The Quantisal™ oral fluid device was used to collect oral fluid samples. The oral fluid-elution buffer mixture (500-µL sample) was extracted with t-butyl methyl ether, and chromatographic separation was performed on a Raptor™ biphenyl column (100 × 2.1 mm ID, 2.7 µm), with a total run time of 13.5 min. Limits of detection were established at three concentrations (0.05, 0.1 or 1 ng/mL) for most analytes, except for acetyl norfentanyl and mescaline (5 ng/mL). Matrix effects were generally <20% and overall extraction recoveries >60%. The highest matrix effect was observed within the synthetic cannabinoid group (PB22, -55.5%). Lower recoveries were observed for 2C-T (47.2%) and JWH-175 (58.7%). Recoveries from the Quantisal™ device were also evaluated for all analytes (56.7-127%), with lower recoveries noted for 25I-NBOMe, valerylfentanyl and mCPP (56.7, 63.0 and 69.9%, respectively). Drug stability in oral fluid was evaluated at 15, 60 and 90 days and at 25, 4 and -20°C. As expected, greater stability was observed when samples were stored at -20°C, but even when frozen, some NPS (e.g., synthetic cannabinoids) showed more than 20% degradation. The method was successfully applied to the analysis of seven authentic oral fluid samples positive for 17 different analytes. The method achieved good sensitivity and simultaneous detection of a wide range of NPS.

Miniaturized extraction method for analysis of synthetic opioids in urine by microextraction with packed sorbent and liquid chromatography-tandem mass spectrometry.

Synthetic opioids are responsible for numerous overdoses and fatalities worldwide. Currently, fentanyl and its analogs are also mixed with heroin, cocaine and methamphetamine, or sold as oxycodone, hydrocodone and alprazolam in counterfeit medications. Microextraction techniques became more frequent in analytical toxicology over the last decade. A method to simultaneously quantify nine synthetic opioids, fentanyl, sufentanil, alfentanil, acrylfentanyl, thiofentanyl, valerylfentanyl, furanylfentanyl, acetyl fentanyl and carfentanil, and two metabolites, norfentanyl and acetyl norfentanyl, in urine samples by microextraction with packed sorbent (MEPS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated. A multivariate optimization was performed to establish the number and speed (stroke) of draw-eject sample cycles and the extraction solvent. The best extraction condition was eight draw-eject sample cycles, with a velocity of 3.6 µL/sec and acetonitrile as elution solvent. Linearity was achieved between 1 to 100 ng/mL, with a limit of detection (LOD) of 0.1 ng/mL and limit of quantification (LOQ) of 1 ng/mL. Imprecision (% relative standard deviation) and bias (%) were less than 12.8% and 5.7%, respectively. The method had good specificity and selectivity when challenged with 10 different matrix sources and 36 pharmaceuticals and drugs of abuse at concentrations of 100 or 500 ng/mL. The method was successfully applied to authentic urine samples. MEPS was an efficient semi-automatic extraction technique, requiring small volumes of organic solvents (640 µL) and sample (200 µL). The cartridges can be cleaned and reused (average of 150 sample extractions/barrel inside and needle).

Analytical quantification, intoxication case series, and pharmacological mechanism of action for N-ethylnorpentylone (N-ethylpentylone or ephylone).

Synthetic cathinones continue to proliferate in clandestine drug markets worldwide. N-ethylnorpentylone (also known as N-ethylpentylone or ephylone) is a popular emergent cathinone, yet little information is available about its toxicology and pharmacology. Here we characterize the analytical quantification, clinical presentation, and pharmacological mechanism of action for N-ethylnorpentylone. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to quantify N-ethylnorpentylone in blood obtained from human cases. Clinical features exhibited by the intoxicated individuals are described. The activity of N-ethylnorpentylone at plasma membrane transporters for dopamine (DAT), norepinephrine (NET) and 5-HT (SERT) was assessed using in vitro assays measuring uptake inhibition and evoked release of [3 H] neurotransmitters in rat brain synaptosomes. Our LC-MS/MS method assayed N-ethylnorpentylone concentrations with limits of detection and quantification of 1 and 5 ng/mL, respectively. Quantitation was linear from 5 to 500 ng/mL, and the method displayed specificity and reproducibility. Circulating concentrations of N-ethylnorpentylone ranged from 7 to 170 ng/mL in clinical cases, and the associated symptoms included palpitations, tachycardia, agitation, hallucinations, coma and death. N-Ethylnorpentylone was a potent inhibitor at DAT (IC50  = 37 nM), NET (IC50  = 105 nM) and SERT (IC50  = 383 nM) but displayed no transporter releasing activity. We present a validated method for quantifying N-ethylnorpentylone in human case work. The drug is a psychomotor stimulant capable of inducing serious cardiovascular and neurological side-effects which can be fatal. In vitro findings indicate that N-ethylnorpentylone exerts its effects by potent blockade of DAT and NET, thereby elevating extracellular levels of dopamine and norepinephrine in the brain and periphery.

Estudo da estabilidade de novas substâncias psicoativas (NPS) em amostras de sangue seco em papel (DBS), e sua aplicação em toxicologia forense / Stability of new psychoactive substances (NPS) in dried blood spots (DBS), and its application in forensic toxicology

Resumo: Introdução: A classe de drogas de abuso conhecida como novas substâncias psicoativas ou, ainda, drogas desenhadas (do inglês new psychoactive substances (NPS) ou designer drugs) é composta por substâncias químicas obtidas a partir de alterações estruturais de substâncias ou mistura de substâncias psicoativas já existentes (e ilícitas), a fim de mimetizar e/ou potencializar os efeitos proporcionados por estas, com a vantagem de circundar a legislação antidrogas vigente. Dentro da classe das NPS, os grupos de maior destaque atualmente são das catinonas sintéticas, dos canabinóides sintéticos e dos NBOMes (feniletilaminas N-2-metoxibenzil substituídas). As catinonas sintéticas, vendidas pela internet como "sais de banho" ou bath salts, são substâncias estruturalmente relacionadas a catinona, um alcalóide presente no Catha edulis (Khat), com propriedades estimulantes. A classe dos NBOMes é derivada da classe dos alucinógenos 2C, a partir da adição de um grupo N-2-metoxibenzil na amina primária. Os NBOMes possuem ação agonista nos receptores de serotonina, especialmente do subtipo 5-HT2A, o que confere os efeitos alucinógenos. Objetivos: Desenvolver e validar métodos para identificação e quantificação de algumas das NPS de maior relevância em amostras de manchas de sangue seco em papel (do inglês dried blood spots, DBS) e comparar a estabilidade entre dois tipos de amostras (DBS e sangue total), em três diferentes temperaturas (ambiente, 4 °C e -20 °C) e períodos de armazenamento. Metodologia: As amostras de DBS e sangue total foram analisadas em cromatógrafo líquido acoplado à espectrômetro de massas com analisador de massas triplo quadrupolar (LC-MS/MS), utilizando os métodos primeiramente desenvolvidos e validados para cada classe de NPS (catinonas sintéticas e NBOMes). Resultados: A técnica de DBS apresentou um aumento significativo da estabilidade das NPS em comparação à técnica convencional de armazenamento de sangue total. Para os NBOMes, observou-se que os compostos eram estáveis no DBS por período de tempo de até 6 meses, nas três temperaturas estudadas, enquanto que no sangue total, os analitos tiveram uma queda maior que 20% da concentração em 15 ou 30 dias em temperatura ambiente e 180 dias para 4 °C. Para as catinonas, em temperatura ambiente, observou-se baixa estabilidade nas duas matrizes. Porém, para armazenamento à 4 °C, observou-se uma queda na concentração inicial maior que 20% com 60 e 90 dias para mefedrona e benzedrona em DBS, respetivamente, contra 45 e 25 dias. Catinonas que possuem grupamento metilenodioxi em sua estrutura, como a butilona e a pentilona, foram mais estáveis, independente da matriz, em comparação àquelas com grupamento alquila no anel aromático, como mefedrona e benzedrona. Conclusão: A técnica de DBS se mostrou vantajosa para análises forenses em comparação à técnica convencional de armazenamento de sangue total. Além de facilitar o armazenamento (por ocupar menos espaço), sua extração se torna mais rápida e facilitada, já que envolve menos etapas, além de tornar possível a identificação dos analitos de interesse por um maior período de tempo, podendo facilmente ser aplicada na rotina laboratorial(AU)

Abstract: Introduction: New psychoactive substances (NPS) or designer drugs is a class of drugs of abuse composed of chemical substances obtained from structural alterations of substances or mixture of existing psychoactive substances (and illicit), in order to mimic and/or maximize their effects, with the advantage of circumventing existing anti-drug legislation. Within the NPS class, the most prominent groups currently are synthetic cathinones, synthetic cannabinoids and NBOMes (phenylethylamines N-2-methoxybenzyl substituted). Synthetic cathinones, sold by the internet as "bath salts", are substances structurally related to cathinone, an alkaloid present in Catha edulis (Khat), with stimulant properties. The class of NBOMes is derived from the hallucinogen class 2C, from the addition of an N-2-methoxybenzyl group to the primary amine. NBOMes have agonist action at serotonin receptors, especially the 5-HT2A subtype, which confers the hallucinogenic effects. Objectives: To develop and validate methods to identify and quantify some of the most relevant NPS in dried blood spots (DBS) samples and to compare the stability between two matrixes (DBS and whole blood), at three different temperatures (ambient, 4 °C and -20 °C) and storage periods. Method: DBS and whole blood samples were analyzed using a liquid chromatography tandem mass spectrometer with a triple quadrupole analyzer (LC-MS/MS), using the developed and validated methods for each class of NPS (synthetic cathinones and NBOMes). Results: The DBS technique showed a significant increase in the NPS stability compared to the conventional whole blood storage technique. For the NBOMes, the compounds were found to be stable in DBS for a time period of up to 6 months, at the three temperatures studied, whereas in whole blood, the analytes had a decreased higher than 20% of the initial concentration in 15 or 30 days at room temperature and 180 days at 4 °C. For the cathinones, at room temperature, low stability was observed in both matrixes. However, for storage at 4 °C, the initial concentration decreased more than 20% at 60 and 90 days for mephedrone and benzedrone in DBS, respectively, against 45 and 25 days. Cathinones having methylenedioxy group in their structure, such as butylone and pentylone, were more stable, independent of the matrix, compared to those with alkyl group on the aromatic ring, such as mephedrone and benzedrone. Conclusion: The DBS technique proved to be advantageous for forensic analysis compared to the conventional storage technique. In addition to occupying less storage space, DBS extraction becomes faster and easier, since it involves fewer steps, besides to make possible to identify the analytes of interest for a longer period of time, which can easily be applied in the laboratory routine(AU)

EASI-IMS an expedite and secure technique to screen for 25I-NBOH in blotter papers.

The increasing number of new psychoactive substances (NPS) and their quick worldwide spreading, often only slightly modified in the form of new derivatives and analogues, have brought the need for fast, wide-ranging, and unequivocal identification methods in clinical and forensic investigations. Because it usually provides secure results, gas chromatography coupled to mass spectrometry (GC-MS) has been routinely employed as the standard technique for the detection of NPS in blotter papers. For 25I-NBOH (N-(2-hydroxybenzyl)-2-(4-iodo-2,5-dimethoxyphenyl)ethan-1-aminium), however, GC-MS analysis of an blotter paper extract leads to incorrect results. In this work, we investigated whether easy ambient sonic-spray mass spectrometry imaging (EASI-IMS), and ambient ionization MS method can be applied directly to the surface of the sample requiring therefore no extraction or sample preparations, would serve as an efficient, sensitive, and secure alternative for 25I-NBOH screening.