Paper-supported polystyrene membranes for micro-solid phase extraction of date-rape drugs from urine: A sustainable analytical approach.

BACKGROUND: The rapid development of micro-solid phase extraction (µ-SPE) procedures with new sorption materials, in particular, based on using natural materials, is currently reported. The production of these sorbents and the entire extraction procedure should support the implementation of Green Analytical Chemistry (GAC) principles. Promising materials are sorbents based on paper, which can be relatively easily modified, among others: by covering it with a polymer membrane. In this work, the practical application of paper-supported polystyrene used in the analysis of urine samples containing selected date-rape drugs (DRD) substances, and evaluation of the entire procedure using GAC metrics is presented. RESULTS: The paper-supported polystyrene membranes were successfully fabricated and characterized. The successful polystyrene coating on the paper was confirmed through ATR-FTIR measurements, ensuring even coverage. The µ-SPE procedure using this material facilitated extraction with a throughput of approximately 120 samples per hour in just a few steps. Throughout the research, a mixture of 100 mM acetic acid:methanol:acetonitrile (70:15:15, v/v/v) was selected as an optimal background electrolyte for capillary electrophoresis - mass spectrometry analysis. Validation results of this method demonstrated its suitability, exhibiting good linearity (R2 > 0.95), low limits of detection (3.1-15 ng mL-1), acceptable precision (<15 %), and recovery for all tested analytes. Furthermore, the greenness evaluation conducted with six different metrics: AGREEprep, AGREE, ComplexGAPI, SPMS, hexagonal metric, and WAC indicated the overall eco-friendliness and sustainability of the method, with minor concerns regarding energy consumption. SIGNIFICANCE: The use of cellulose paper with polystyrene membranes for µ-SPE provides a versatile and eco-friendly extraction method for detecting DRDs in urine samples. The presented work is an example of the use of GAC metrics in the evaluation of the analytical procedure. The optimized PT-µ-SPE/CE-MS method allows for minimized reagent usage and waste production. Moreover, the method proves to be sustainable and efficient for forensic toxicology analysis.

[NMR Study of the Discrimination of Enantiomers of Methamphetamine and Its Raw Materials Using Chiral Solvating Agents].

Some controlled substances, such as stimulants and narcotics, have asymmetric carbons in their molecules. Because the enantiomers do not always show the same pharmacological effects, and there are substances with different controls due to differences in their stereochemistry, a simple and unambiguous method for assessment of the composition of enantiomers is necessary. In this study, to develop a simple and rapid stereoscopic identification method for methamphetamine and its raw materials (ephedrine and pseudoephedrine), the 1H-NMR method was studied using three commercially available chiral solvating agents (CSAs); 1,1'-bi(2-naphthol)(BINOL), 2,2,2-trifluoro-1-(9-anthryl)ethanol (TFAE) and α-methoxy-α-(trifluoromethyl)phenylacetic acid (MTPA). In addition, the accuracy of the optical purity, which was measured using samples mixed with enantiomers in various ratios, was investigated. The NMR peaks of the enantiomers were separated by adding (R)- or (S)-form of BINOL, TFAE or MTPA to the chloroform-d solution of methamphetamine, ephedrine or pseudoephedrine. A sufficient discrimination of enantiomers was obtained by adding about 10 equal amounts of each CSA to the solutions. With regard to the optical purity, it was possible to determine accurately the mixing of small amounts of enantiomers of about 5% even if the NMR peaks did not reach the baseline separation, when impurity peaks do not overlap. This method will be one of the useful techniques for the rapid and simple discrimination of enantiomers of illegal methamphetamine and its raw materials.

Providing illicit drugs results in five seconds using ultra-portable NIR technology: An opportunity for forensic laboratories to cope with the trend toward the decentralization of forensic capabilities.

The analysis of illicit drugs faces many challenges, mainly regarding the production of timely and reliable results and the production of added value from the generated data. It is essential to rethink the way this analysis is operationalised, in order to cope with the trend toward the decentralization of forensic applications. This paper describes the deployment of an ultra-portable near-infrared detector connected to a mobile application. This allows analysis and display of results to end users within 5s. The development of prediction models and their validation, as well as strategies for deployment within law enforcement organizations and forensic laboratories are discussed.

Fentanyl Detection Using Eosin Y Paper Assays.

Eosin Y is a potential new color test for use in detecting illicit drugs that has not been extensively studied. In the present study, a variety of drugs of abuse and fentanyl analogues were tested to determine which drugs will bind to eosin Y, which functional groups are capable of binding and eliciting a color change, and a mechanism for eosin Y binding to fentanyl. Further, these agents were combined with common cutting agents and other drugs of abuse in order to determine the fentanyl detection limit in a drug mixture using an eosin Y test strip. Additionally, cobalt thiocyanate was used to determine whether the combination of cobalt thiocyanate and eosin Y has the potential to identify fentanyl. Through the testing performed, we concluded that (i) Eosin Y is capable of detecting low amounts of fentanyl down to 1%, (ii) Eosin Y binds to select tertiary amines to produce an orange to pink color change, and (iii) Eosin Y binds to the nonpiperidine ring nitrogen of fentanyl as a primary binding site and the piperidine ring nitrogen as a secondary binding site. While the cobalt thiocyanate assay detected 1% fentanyl in some of the mixtures, eosin Y detected 1% fentanyl in all mixtures. Finally, eosin Y was able to detect fentanyl in forensic case samples containing heroin and various cutting agents. Based on our results, eosin Y has the potential to screen for fentanyl and fentanyl analogues and can detect fentanyl in low amounts when mixed with common cutting agents.

MASS SPECTROMETRY ANALYSIS OF DRUGS OF ABUSE: CHALLENGES AND EMERGING STRATEGIES.

Mass spectrometry has been the "gold standard" for drugs of abuse (DoA) analysis for many decades because of the selectivity and sensitivity it affords. Recent progress in all aspects of mass spectrometry has seen significant developments in the field of DoA analysis. Mass spectrometry is particularly well suited to address the rapidly proliferating number of very high potency, novel psychoactive substances that are causing an alarming number of fatalities worldwide. This review surveys advancements in the areas of sample preparation, gas and liquid chromatography-mass spectrometry, as well as the rapidly emerging field of ambient ionization mass spectrometry. We have predominantly targeted literature progress over the past ten years and present our outlook for the future. © 2020 Periodicals, Inc. Mass Spec Rev.

Mix of new substances psychoactive, NPS, found in blotters sold in two Colombian cities.

The new psychoactive substances (NPS) in Colombia are detected by national authorities, in blotters strip, in different circumstances and places: airports, music concerts, discos and parks. Blotters are marketed as LSD and cause several cases of intoxication and death in some consumers: due to acute intoxication or when mixed with other drugs and may have different effects on the central nervous system (CNS). This study was conducted to research into and identify the chemical composition of the drugs impregnated in the blotters sold in two Colombian cities. This research provides the analysis of 70 doses coming from forensic cases of the Colombian Attorney General's Office in Bogota and from the Laboratory of Narcotics of the Colombian National Institute of Legal Medicine and Forensic Sciences (North Headquarter) in Barranquilla. Mixtures of drugs, such as DOB, 25I-NBOMe, MDMA and 25I-NBOMe imine were found within the blotters through gas chromatography coupled to mass spectrometry (CGMS); these drugs are classified by international authorities as NPS belonging to the phenylethylamines group. The results clearly warn about a growing public health problem in the country.

Development of pipette tip-based poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith for the extraction of drugs of abuse from oral fluid samples.

In this work, a monolithic polymer based on poly(methacrylic acid-co-ethylene glycol dimethacrylate) (MAA-co-EDMA) was prepared inside 200 µL pipette tips for the extraction of drug of abuse from oral fluid samples. After an appropriate surface tip modification, several polymerization mixtures with different monomer/cross-linker ratios, and percentage of porogen were studied. The most appropriate monolith to easily flow organic solvents and oral fluid samples was prepared with a MAA/EDMA ratio of 8:92 wt/wt and dodecanol containing 10 wt% toluene, as porogenic solvent. Parameters affecting the extraction procedure were evaluated and the monolith was characterized in terms of binding capacity, reusability, and precision, using α-pyrrolidinovalerophenone as model compound. Cocaine, diazepam, methamphetamine and 20 new psychoactive substances were determined in oral fluids, using the synthesized poly(MAA-co-EDMA) monolith in-tip on an eight-channel micropipette extraction and ultra-high performance liquid chromatography tandem mass spectrometry. Appropriate recoveries were obtained, ranging from 64 to 115%, with limit of detection values from 0.03 to 0.6 µg L-1, and a high precision with relative standard deviation values lower than 10% for all the evaluated drugs.

A Photoluminescent Colorimetric Probe of Bovine Serum Albumin-Stabilized Gold Nanoclusters for New Psychoactive Substances: Cathinone Drugs in Seized Street Samples.

Screening of illicit drugs for new psychoactive substances-namely cathinone-at crime scenes is in high demand. A dual-emission bovine serum albumin-stabilized gold nanoclusters probe was synthesized and used for quantitation and screening of 4-chloromethcathinone and cathinone analogues in an aqueous solution. The photoluminescent (PL) color of the bovine serum albumin-stabilized Au nanoclusters (BSA-Au NCs) probe solution changed from red to dark blue during the identification of cathinone drugs when excited using a portable ultraviolet light-emitting diodes lamp (365 nm). This probe solution allows the PL color-changing point and limit of detection down to 10.0 and 0.14 mM, respectively, for 4-chloromethcathinone. The phenomenon of PL color-changing of BSA-Au NCs was attributed to its PL band at 650 nm, quenching through an electron transfer mechanism. The probe solution was highly specific to cathinone drugs, over other popular illicit drugs, including heroin, cocaine, ketamine, and methamphetamine. The practicality of this BSA-Au NCs probe was assessed by using it to screen illicit drugs seized by law enforcement officers. All 20 actual cases from street and smuggling samples were validated using this BSA-Au NCs probe solution and then confirmed using gas chromatography-mass spectrometry. The results reveal this BSA-Au NCs probe solution is practical for screening cathinone drugs at crime scenes.

Online Sol-gel Capillary Microextraction-Mass Spectrometry (CME-MS) Analysis of Illicit Drugs.

Providing rapid and sensitive sample cleanup, sol-gel capillary microextraction (CME) is a form of solid phase microextraction (SPME). The capillary format of CME couples easily with mass spectrometry (MS) by employing sol-gel sorbent coatings in inexpensive fused silica capillaries. By leveraging the syringe pump and six-port valve readily available on the commercial MS, we can obviate the need for chromatography for samples as complex as urine in quantitative assays. Two different sol-gel materials were studied as microextraction sorbents: one with a single ligand of octadecyl (C18) and the other with a dual-ligand combination of C18 and phenyl (Phe) groups. The CME-MS method was optimized for flow rate and solvent desorption and studied for overall microextraction performance between the two sorbents studied. We extract illicit drugs including cocaine, heroin, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, and oxycodone, proving good run-to-run reproducibility (RSD% < 10%) and low detection limits (< 10 ng mL-1). The dual-ligand sorbent demonstrated superior performance due to typical hydrophobic properties of C18 as well as potential π-π interactions of the Phe functionality and the aromatic moiety common to many drugs. This study demonstrates the advantage of fine-tuning sol-gel sorbents for application-specific CME-MS. We apply our method to the analysis of various drugs in synthetic and human urine samples and show low carryover effect (~ 5%) and low matrix effect in the presence of the urine matrix. Thus, the sol-gel CME-MS technique described herein stands to be an attractive alternative to other SPME-MS techniques.

Drug detection dogs at Australian outdoor music festivals: Deterrent, detection and iatrogenic effects.

BACKGROUND: Recent drug-related deaths at Australian music festivals have led to increasing concern about the risk of future harm, but contention about how to effectively respond. One hotly debated strategy has been the use of drug detection dogs which currently operate at festivals across Australia, despite claims they are ineffective and contribute to risky drug use practices. This paper aims to investigate responses to the expected presence, and sightings, of drug dogs at the last festival attended. METHODS: An anonymous online survey was completed by almost 2000 Australian festival-goers. The largest subsample used in the analyses for this paper (n= 647) was 59% male and had a median age of 20 (IQR = 18-22). RESULTS: Of those who expected dogs to be present at their last festival (n= 647), only 4% reported that this threat led them to decide not to take drugs. Other responses included: concealing their drugs well (48%), getting someone else to carry their drugs (15%), buying their drugs inside (11%), taking less easily detected drugs (10%) and taking drugs before entering (7%). Of those who carried drugs in (n= 418), 10% concealed them internally and 1% swallowed them to retrieve inside. Of those who had drugs on their person when seeing a dog (n= 189), 10% reported consuming drugs in response. No respondents reported being detected with drugs due to a positive identification. CONCLUSION: Almost all festival-goers surveyed did not report being deterred from drug usage by the expected presence of drug dogs. Instead, a variety of alternative responses to avoid detection were reported, many of which could place festival-goers at greater risk of experiencing drug-related harms. In the face of mounting evidence of both ineffectiveness and iatrogenic effects, the use of drug detection dogs at Australian music festivals should be urgently reconsidered.

The genus Datura L. (Solanaceae) in Mexico and Spain - Ethnobotanical perspective at the interface of medical and illicit uses.

ETHNOPHARMACOLOGICAL RELEVANCE: The different species of the genus Datura have been used traditionally by some pre-Columbian civilizations, as well as in medieval rituals linked to magic and witchcraft in both Mexico and Europe. It is also noteworthy the use of different alkaloids obtained from the plants for medicinal purposes in the treatment of various groups of diseases, especially of the respiratory and muscularskeletal systems. AIM OF THE STUDY: A review of the ethnobotanical uses of the genus Datura in Mexico and Spain has been conducted. We focus on the medicinal and ritualistic uses included in modern ethnobotanical studies, emphasizing the historical knowledge from post-colonial American Codices and medieval European texts. Datura's current social emergency as a drug of recreation and leisure, as well as its link to crimes of sexual abuse is also considered. The work is completed with some notes about the distribution and ecology of the different species and a phytochemical and pharmacological review of Datura alkaloids, necessary to understand their arrival in Europe and the ethnobotanical uses made since then MATERIALS AND METHODS: A literature review and compilation of information on traditional medicinal uses of the genus has been carried out from the main electronic databases. Traditional volumes (codices) have also been consulted in libraries of different institutions. Consultations have been made with the National Toxicological Services of Spain and Mexico for toxicological data. RESULTS: A total of 118 traditional uses were collected in both territories, 111 medicinal ones to be applied in 76 conditions or symptoms included in 13 pathological groups. Although there are particular medicinal uses in the two countries, we found up to 15 similar uses, of which 80% were previously mentioned in post-Colonial American codices. Applications in the treatment of asthma and rheumatism are also highlighted. Apart from medicinal uses, it is worth noting their cultural and social uses, in the case of Mexico relating to diseases such as being scared, astonishment or falling in love, and in the case of Spain, as a recreational drug and lately, for criminal purposes. CONCLUSIONS: This review highlights the variety of uses traditionally given to the different species in both territories. The fact that most of the coincident or similar uses in both countries also appear in the classical codices can be found an example of the flow, not only of the plants from America to Europe, but also of their associated information. It is also relevant that particular uses have derived in both countries, reflecting the difference in the cultural factors and traditions linked to rituals and cultural practices. Finally, the significant growth of Datura consumption in recent years as a drug of leisure and recreation, as well as in crimes of sexual submission, should be considered as research of maximum relevance in the field of forensic botany and toxicology.

Development of a quantitative method for the analysis of cocaine analogue impregnated into textiles by Raman spectroscopy.

Cocaine trafficking in the form of textile impregnation is routinely encountered as a concealment method. Raman spectroscopy has been a popular and successful testing method used for in situ screening of cocaine in textiles and other matrices. Quantitative analysis of cocaine in these matrices using Raman spectroscopy has not been reported to date. This study aimed to develop a simple Raman method for quantifying cocaine using atropine as the model analogue in various types of textiles. Textiles were impregnated with solutions of atropine in methanol. The impregnated atropine was extracted using less hazardous acidified water with the addition of potassium thiocyanate (KSCN) as an internal standard for Raman analysis. Despite the presence of background matrix signals arising from the textiles, the cocaine analogue could easily be identified by its characteristic Raman bands. The successful use of KSCN normalised the analyte signal response due to different textile matrix background interferences and thus removed the need for a matrix-matched calibration. The method was linear over a concentration range of 6.25-37.5 mg/cm2 with a coefficient of determination (R2 ) at 0.975 and acceptable precision and accuracy. A simple and accurate Raman spectroscopy method for the analysis and quantification of a cocaine analogue impregnated in textiles has been developed and validated for the first time. This proof-of-concept study has demonstrated that atropine can act as an ideal model compound to study the problem of cocaine impregnation in textile. The method has the potential to be further developed and implemented in real world forensic cases.

Spatial (bio)accumulation of pharmaceuticals, illicit drugs, plasticisers, perfluorinated compounds and metabolites in river sediment, aquatic plants and benthic organisms.

Organic contaminants such as pharmaceuticals, personal care products (PPCPs) and other emerging contaminants (ECs) are known to persist in the aquatic environment and many are indicated as endocrine, epigenetic, or other toxicants. Typically, the study of PPCPs/ECs in the aquatic environment is limited to their occurrence dissolved in river water. In this study, accumulation and spatial distribution of thirteen PPCPs/ECs were assessed in aquatic sediment (n = 23), periphyton (biofilm, n = 8), plants Callitriche sp. (n = 8) and Potamogeton sp. (n = 7) as well as amphipod crustaceans (Gammarus pulex, n = 10) and aquatic snails (Bithynia tentaculata, n = 9). All samples (n = 65) were collected from the Hogsmill, Blackwater and Bourne Rivers in southern England. Targeted PPCPs/ECs included pharmaceuticals, plasticisers, perfluorinated compounds, illicit drugs and metabolites. Extraction from solid matrices occurred using ultrasonic-assisted extraction followed by an in-house validated method for solid-phase extraction and subsequent liquid-chromatography tandem mass-spectrometry. Field-derived bioconcentration-factors and biota-sediment accumulation-factors were determined for all studied biota. Residues of studied contaminants were found in all sediment and biota. Concentrations of contaminants were generally higher in biota than sediment. Evidence suggests that the studied aquatic plants may effectively degrade bisphenol-A into its main transformation product hydroxyacetophenone, potentially mediated by cytochrome p450 and internalisation of contaminants into the cellular vacuole. A positive association between both hydrophobicity and PFC chain length and contaminant accumulation was observed in this work. Only PFCs, plasticisers and HAP were classified as either 'bioaccumulative' or 'very bioaccumulative' using BCF criteria established by guidelines of four governments. Contaminants appeared to be differentially bioaccumulative in biota, indicating there may be a need for a species-specific BCF/BSAF classification system. These data form a detailed accounting of PPCP/EC fate and distribution in the aquatic environment highlighting accumulation at lower trophic levels, a potential source for higher organisms.

Synthesis of a novel polymeric magnetic solid phase extraction adsorbent for selective extraction of amphetamine from urine samples coupled with high performance liquid chromatography.

A novel pH-responsive block copolymer (Poly ethylene glycol-b-poly (N,N-dimethylaminoethylmethacrylate-co-maleic acid) was designed for the decoration and stabilization of magnetic nanoparticles (MNPs) as an efficient magnetic nano adsorbent for extraction of amphetamine (AM) from biological urine samples to be determined by high performance liquid chromatography-ultra violet detector (HPLC-UV). Full characterization of the synthesized polymeric magnetic nanoparticles (PMNPs) were followed by various techniques like Fourier transform infrared (FT-IR) spectroscopy, powder x-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). Important extraction parameters including pH, amount of sample volume, amount of adsorbent, type and amount of extraction organic solvent, time of extraction and desorption, agitation rate (rpm), and ionic strength of the extraction medium were studied and optimized. Under optimized extraction conditions, good linearity was observed in the concentration range of 30-2000 ng/mL for AM. The amount of the qe was calculated as 0.18 (mg/g). The method was applied in determination of AM from positive urine samples with the recovery of 99.84%. Results indicated that the proposed method could be applied in clinical and forensic laboratories for simple, selective, and fast determination of AM from urine samples.

Sample preparation method for the combined extraction of ethyl glucuronide and drugs of abuse in hair.

Often in hair analysis, a small hair sample is available while the analysis of a multitude of structurally diverse substances with different concentration ranges is demanded. The analysis of the different substances often requires different sample preparation methods, increasing the amount of required hair sample. When segmental hair analysis is necessary, the amount of hair sample needed is further increased. Therefore, the required sample amount for a full analysis can quickly exceed what is available. To combat this problem, a method for the combined hair sample preparation using a single extraction procedure for analysis of ethyl glucuronide with liquid chromatography-multistage fragmentation mass spectrometry/multiple reaction monitoring (LC-MS3 /MRM) and common drugs of abuse with LC-MRM was developed. The combined sample preparation is achieved by separating ethyl glucuronide from the drugs of abuse into separate extracts by fractionation in the solid-phase extraction step during sample clean-up. A full validation for all substances for the parameters selectivity, linearity, limit of detection, limit of quantification, accuracy, precision, matrix effects, and recovery was successfully completed. The following drugs of abuse were included in the method: Amphetamine; methamphetamine; 3,4-methylenedioxy-N-methylamphetamine (MDMA); 3,4-methylenedioxyamphetamine (MDA); 3,4-methylenedioxy-N-ethylamphetamine (MDE); morphine; 6-monoacetylmorphine; codeine; acetylcodeine; cocaine; benzoylecgonine; norcocaine; cocaethylene; methadone; 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and methylphenidate. In conclusion, as only 1 sample preparation is needed with 1 aliquot of hair, the presented sample preparation allows an optimal analysis of both ethyl glucuronide and of the drugs of abuse, even when the sample amount is a limiting factor.

Detection of Contact Traces of Powdery Substances.

The current practice in securing the contact traces of chemical substances taken from clothes belonging to a person suspected of manual handling explosives is focused on pockets and cuffs. The outerwear worn by people who had contact with fluorescent powders that simulate explosives and drugs was the subject of this study. Clothes were first exposed to the test substance for a period of time and then analyzed by fluorescence methods to determine the location of the highest quantity of traces. The results obtained from the study confirm that the areas with the highest concentration of powdery traces are different from those suggested by current forensic practice. They appear to be promising for a more efficient identification of the suspects involved in illegal manufacturing of drugs of abuse or explosives. Moreover, they may be helpful for developing the methodology for handling the evidence material in the forensic clothing examination process.

Validation of an ultra-high-performance liquid chromatography-tandem mass spectrometry method to quantify illicit drug and pharmaceutical residues in wastewater using accuracy profile approach.

The analysis of biomarkers in wastewater has become a common approach to assess community behavior. This method is an interesting way to estimate illicit drug consumption in a given population: by using a back calculation method, it is therefore possible to quantify the amount of a specific drug used in a community and to assess the consumption variation at different times and locations. Such a method needs reliable analytical data since the determination of a concentration in the ngL-1 range in a complex matrix is difficult and not easily reproducible. The best analytical method is liquid chromatography - mass spectrometry coupling after solid-phase extraction or on-line pre-concentration. Quality criteria are not specially defined for this kind of determination. In this context, it was decided to develop an UHPLC-MS/MS method to analyze 10 illicit drugs and pharmaceuticals in wastewater treatment plant influent or effluent using a pre-concentration on-line system. A validation process was then carried out using the accuracy profile concept as an innovative tool to estimate the probability of getting prospective results within specified acceptance limits. Influent and effluent samples were spiked with known amounts of the 10 compounds and analyzed three times a day for three days in order to estimate intra-day and inter-day variations. The matrix effect was estimated for each compound. The developed method can provide at least 80% of results within ±25% limits except for compounds that are degraded in influent.

Separation of ortho, meta and para isomers of methylmethcathinone (MMC) and methylethcathinone (MEC) using LC-ESI-MS/MS: Application to forensic serum samples.

Separation and identification of positional isomers is an important issue in forensic toxicology, particularly in the context of new psychoactive substances (NPS). Despite the structural similarity, positional isomers often show different pharmacological properties and thus can exhibit dramatic differences with respect to their toxicity. Additionally, besides these pharmacological and toxicological effects, the legal status is also of great importance. We present a sensitive and selective LC-MS/MS method to separate the ortho, meta and para isomers of methylmethcathinone (MMC) and methylethcathinone (MEC) using a core-shell biphenyl analytical column. Reliability of the method was confirmed under consideration of the validation parameters selectivity, linearity, accuracy and precision, analytical limits, processed sample stability, matrix effects and recovery. Linearity was demonstrated over the entire calibration range from 5 to 250ng/ml with the use of a 1/x2 weighting. Appropriate quantification and detection limits (LLOQ=5ng/ml, LOD<2ng/ml) could be achieved. Application of the method to real serum samples collected between June 2014 and August 2016 revealed the proof of a recent MMC or MEC consumption, respectively, in eight cases. Isomers of MMC could be detected in three of these eight cases, of which two were positive for 3-MMC and one was positive for 2-MMC. The other samples were tested positively for 3-MEC. In none of the samples 4-MMC, 2-MEC or 4-MEC could be detected. Only substances that were not governmentally controlled at that time could be detected, reflecting the rapid response of the recreational drug market to newly enacting drug laws.