Position of chromatographic techniques in screening for detection of drugs or poisons in clinical and forensic toxicology and/or doping control

Residents' Knowledge regarding Recreational Drug Screening Immunoassays at a Swiss Hospital Group

Introduction

In case of suspected acute recreational drug toxicity, immunoassays are commonly used as diagnostic tools. Although easy to handle, understanding of their limitations is necessary for a correct interpretation of the results. The aim of this project was to investigate residents' knowledge regarding drug screening immunoassays at a Swiss hospital group.

Methods

All residents of a large hospital group in Switzerland were invited by e-mail to participate in an anonymous survey. Following ten multiple choice questions on drug screening tests, the participants were also asked about their demographics, whether they used drug screening tests on a regular basis, and how confident they felt in their ability to interpret test results.

Results

The ten knowledge questions were answered by 110 of the 1026 residents (11%). Among the 108 participants with available demographics, 90% were 25-35 years old, 63% were female, and 70% were at least in their 4th year of residency. The median score of correct answers was 4 out of 10 (range 0-7) and in 50% of the questions, the correct answer was the most frequently selected response. No significant differences in the knowledge scores were found based on the training, confidence level, or the frequency of drug tests used in daily work.

Conclusion

This survey revealed widespread knowledge gaps among residents regarding the interpretation of immunoassay-based drug test results. These findings can be used to implement educational measures on this topic and might provide a basis for targeted information on common pitfalls to be included in laboratory reports.

Emerging global trends and development in forensic toxicology: A review

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

Dilute and shoot approach for toxicology testing

Toxicology testing is performed in clinical settings, forensic settings, and for controlling doping. Drug screening is a toxicology test to determine if drugs are present in biological samples. The most common specimen type for drug testing is urine, as drugs and/or their metabolites are often more concentrated in the urine, extending the detection window of drugs. The dilute-and-shoot method is a simple procedure used in toxicology testing, where a sample is diluted before being directly injected into the liquid chromatography-mass spectrometry (LC-MS) system. This method is easy, quick, and cost-saving, and can be used for protein-poor liquid specimens such as urine. Thus, it is reasonable and attractive for busy toxicology laboratories to combine the dilute-and-shoot method with high-resolution hyphenated-MS for urine drug screening. This method has several disadvantages, including a suboptimal detection capability for certain analytes, as well as interference from co-eluting matrix components called matrix effects, in which co-eluting matrix molecules alter the ionization efficiency of the analyte molecules at the ionization source in LC-MS, altering (mostly reducing) the analyte detection capability. The matrix effect testing is essential for the validation of LC-MS-based assays. A reasonable approach to addressing these undesirable effects would be to minimize these components. The most straightforward approach is to reduce the amounts of matrix components by using a higher dilution of the specimen and a lower volume for specimen injection. Optimization of the chromatographic separation is another reasonable approach for reducing co-eluting matrix components with the analyte.

Current state-of-the-art approaches for mass spectrometry in clinical toxicology: an overview

INTRODUCTION

Hyphenated mass spectrometry (MS) has evolved into a very powerful analytical technique of high sensitivity and specificity. It is used to analyze a very wide spectrum of analytes in classical and alternative matrices. The presented paper will provide an overview of the current state-of-the-art of hyphenated MS applications in clinical toxicology primarily based on review articles indexed in PubMed (1990 to April 2023).

AREAS COVERED

A general overview of matrices, sample preparation, analytical systems, detection modes, and validation and quality control is given. Moreover, selected applications are discussed.

EXPERT OPINION

A more widespread use of hyphenated MS techniques, especially in systematic toxicological analysis and drugs of abuse testing, would help overcome limitations of immunoassay-based screening strategies. This is currently hampered by high instrument cost, qualification requirements for personnel, and less favorable turnaround times, which could be overcome by more user-friendly, ideally fully automated MS instruments. This would help making hyphenated MS-based analysis available in more laboratories and expanding analysis to a large number of organic drugs, poisons, and/or metabolites. Even the most recent novel psychoactive substances (NPS) could be presumptively identified by high-resolution MS methods, their likely presence be communicated to treating physicians, and be confirmed later on.

Development and Validation of a Non-Targeted Screening Method for Most Psychoactive, Analgesic, Anaesthetic, Anti-Diabetic, Anti-Coagulant and Anti-Hypertensive Drugs in Human Whole Blood and Plasma Using High-Resolution Mass Spectrometry

(1) Background: In toxicological laboratories, various screening methods can be used to identify compounds involved in intoxication. High-resolution mass spectrometry has been increasingly used in this context for the last years, because of its sensitivity and reliability. Here, we present the development and validation of a screening method that uses liquid chromatography coupled with a high-resolution mass spectrometer. (2) Methods: This method required only 100 µL of whole blood or plasma sample. Pretreatment consisted of a rapid and simple deproteinisation with methanol/acetonitrile and zinc sulphate. This new assay was validated according to international guidelines. (3) Results: To perform the method validation, 53 compounds were selected. The selection criteria were as follows: various chemical structures and therapeutic families (>15), large m/z distribution, positive or negative ionisation mode, and various elution times. The assays showed high selectivity and specificity, with optimal process efficiency. The identification limits, determined using predefined criteria, were established at sub-therapeutic or therapeutic concentrations. Applicability was evaluated using spiked plasma controls and external quality controls. (4) Conclusions: The new method was then successfully applied to routine clinical and forensic samples.

Qualitative and quantitative determination of butanol in latex paint by fast gas chromatography proton transfer reaction mass spectrometry

Butanol is a common organic solvent used in latex paint, and one of its isomers, tert-butanol, is toxic and can cause potential harm to the human body. Therefore, it is of great significance to develop a qualitative and quantitative detection method for butanol isomers. In this study, we combined the advantages of rapid detection of proton transfer reaction mass spectrometry (PTR-MS) with the separation and qualitative capabilities of gas chromatography-mass spectrometry (GC-MS) to achieve the detection of isomers, building a fast gas chromatography proton transfer reaction mass spectrometry (FastGC-PTR-MS) equipment. Firstly, the developed technology was optimized using standard samples of several common volatile organic compounds. The retention times of acetonitrile, acetone, and alcohols were less than 50 s, and the retention times of the benzene series were less than 110 s, on the premise that these isomers could be basically separated (resolution R > 1.0). Compared with a commercial GC-MS equipment, the detection times were shortened by 5-6 times and 2-4 times, respectively. Then the FastGC-PTR-MS was applied to detect the isomers of butanol in latex paint. The results showed that the headspace of brand D latex paint mainly contained five substances: tert-butanol, n-butanol, acetaldehyde, methanol, and acetone. Tert-butanol and n-butanol could be completely separated (R > 1.5). The concentration of tert-butanol was 4.41 ppmv, far below the 100 ppmv maximum allowable workplace concentration. The developed FastGC-PTR-MS can be used for rapid qualitative and quantitative detection of butanol isomers in latex paint. The new equipment has the potential to play an important role in indoor environmental safety applications.

Follicular Fluid: A Powerful Tool for the Understanding and Diagnosis of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) represents one of the leading causes of anovulatory infertility and affects 5% to 20% of women worldwide. Until today, both the subsequent etiology and pathophysiology of PCOS remain unclear, and patients with PCOS that undergo assisted reproductive techniques (ART) might present a poor to exaggerated response, low oocyte quality, ovarian hyperstimulation syndrome, as well as changes in the follicular fluid metabolites pattern. These abnormalities originate a decrease of Metaphase II (MII) oocytes and decreased rates for fertilization, cleavage, implantation, blastocyst conversion, poor egg to follicle ratio, and increased miscarriages. Focus on obtaining high-quality embryos has been taken into more consideration over the years. Nowadays, the use of metabolomic analysis in the quantification of proteins and peptides in biological matrices might predict, with more accuracy, the success in assisted reproductive technology. In this article, we review the use of human follicular fluid as the matrix in metabolomic analysis for diagnostic and ART predictor of success for PCOS patients.

Comparison of LC-MS and LC-DAD Methods of Detecting Abused Piperazine Designer Drugs

Recreational use of piperazine designer drugs is a serious threat to human health. These compounds act on the body in a similar fashion to illegal drugs. They induce psychostimulatory effects as well as visual and auditory hallucinations to varying degrees. In many cases of poisoning and deaths, the presence of two or even several psychoactive substances have been demonstrated. Piperazine derivatives are often found in such mixtures and pose a great analytical problem during their identification. Additionally, some piperazine derivatives can be detected in biological material as a result of metabolic changes to related drugs. Therefore, it is necessary to correctly identify these compounds and ensure repeatability of determinations. This article presents a comparison of the methods used to detect abused piperazine designer drugs using liquid chromatography in combination with a diode-array detector (LC-DAD) or mass spectrometer (LC-MS). Each of methods can be used independently for determinations, obtaining reliable results in a short time of analysis. These methods can also complement each other, providing qualitative and quantitative confirmation of results. The proposed methods provide analytical confirmation of poisoning and may be helpful in toxicological diagnostics.

Rapid Targeted Method of Detecting Abused Piperazine Designer Drugs

Piperazine derivatives belong to the popular psychostimulating compounds from the group of designer drugs. They are an alternative to illegal drugs such as ecstasy and amphetamines. They are being searched by consumers for recreational use due to their stimulating and hallucinogenic effects. Many NPS-related poisonings and deaths have been reported where piperazines have been found. However, a major problem is the potential lack of laboratory confirmation of the involvement of piperazine derivatives in the occurrence of poisoning. Although many methods have been published, piperazine derivatives are not always included in a routine analytical approach or targeted toxicological analysis. There is an increasing need to provide qualitative evidence for the presence of piperazine derivatives and to ensure reproducible quantification. This article describes a new rapid method of detecting piperazine derivatives in biological material, using LC-MS. All target analytes were separated in a 15 min run time and identified based on the precursor ion, at least two product ions, and the retention time. Stable isotopically labeled (SIL) internal standards: BZP-D7, mCPP-D8 and TFMPP-D4 were used for analysis, obtaining the highest level of confidence in the results. The proposed detection method provides the analytical confirmation of poisoning with piperazine designer drugs.

Performance- and image-enhancing drug use in the community: use prevalence, user demographics and the potential role of wastewater-based epidemiology

Performance- and image-enhancing drug (PIED) misuse is a significant public health issue. Currently, seizure data, surveys, anti-doping testing, and needle service provider data are used to estimate PIED use in populations. These methods are time consuming, single point-in-time measurements that often consist of small sample sizes and do not truly capture PIED prevalence. Wastewater-based epidemiology (WBE) has been used globally to assess and monitor licit and illicit drug consumption within the general community. This method can objectively cover large populations as well as specific subpopulations (gyms, music festivals, prisons), and has potential as a complementary monitoring method for PIED use. Information obtained through WBE could be used to aid public health authorities in developing targeted prevention and education programmes. Research on PIED analysis in wastewater is limited and presents a significant gap in the literature. The focus is on anabolic steroids, and one steroid alternative currently growing in popularity; selective androgenic receptor modulators. This encompasses medical uses, addiction, prevalence, user typology, and associated public health implications. An overview of WBE is described including its benefits, limitations and potential as a monitoring method for PIED use. A summary of previous work in this field is presented. Finally, we summarise gaps in the literature, future perspectives, and recommendations for monitoring PIEDs in wastewater.

Synthetic drugs of abuse

Synthetic drugs of abuse contain various psychoactive substances. These substances have recently emerged as novel drugs of abuse in public; thus, they are known as novel psychoactive substances (NPS). As these compounds are artificially synthesized in a laboratory, they are also called designer drugs. Synthetic cannabinoids and synthetic cathinones are the two primary classes of NPS or designer drugs. Synthetic cannabinoids, also known as "K2" or "Spice," are potent agonists of the cannabinoid receptors. Synthetic cathinones, known as "Bath salts," are beta-keto amphetamine derivatives. These compounds can cause severe intoxication, including overdose deaths. NPS are accessible locally and online. NPS are scheduled in the US and other countries, but the underground chemists keep modifying the chemical structure of these compounds to avoid legal regulation; thus, these compounds have been evolving rapidly. These drugs are not detectable by traditional drug screening, and thus, these substances are mainly abused by young individuals and others who wish to avoid drug detection. These compounds are analyzed primarily by mass spectrometry.

Hyphenated high-resolution mass spectrometry-the "all-in-one" device in analytical toxicology?

This trend article reviews papers with hyphenated high-resolution mass spectrometry (HRMS) approaches applied in analytical toxicology, particularly in clinical and forensic toxicology published since 2016 and referenced in PubMed. The article focuses on the question of whether HRMS has or will become the all-in-one device in these fields as supposed by the increasing number of HRMS presentations at scientific meetings, corresponding original papers, and review articles. Typical examples for the different application fields are discussed such as targeted or untargeted drug screening, quantification, drug metabolism studies, and metabolomics approaches. Considering the reviewed papers, HRMS is currently the only technique that fulfills the criteria of an all-in-one device for the various applications needed in analytical toxicology.

Graphical abstract

Pitfalls in drug testing by hyphenated low- and high-resolution mass spectrometry

This paper reviews various pitfalls observed during developing, validation, application, and interpretation of drug testing approaches using GC-MS and low- and high-resolution LC-MS. They include sampling and storage of body samples, sample adulteration and contamination, analyte stability, sample preparation without or with cleavage of conjugates, extraction, derivatization, internal standardization, false negative and positive results by GC-MS or LC-MS screening and/or confirmation procedures including artifact formation, ion suppression or enhancement by electrospray ionization, and finally pitfalls in data interpretation. Conclusions and prospects close the Tutorial.

Diagnosis of acute intoxications in critically ill patients: focus on biomarkers - part 1: epidemiology, methodology and general overview

Acute intoxications account for a significant proportion of the patient population in intensive care units and sedative medications, ethanol, illicit drugs, inhalable poisons and mixed intoxications are the most common causes. The aim of this article is to describe biomarkers for screening and diagnosis of acute intoxications in critically ill patients. For this purpose, a survey of the relevant literature was conducted, and guidelines, case reports, expert assessments, and scientific publications were reviewed. In critical care, it should always be attempted to identify and quantify the poison or toxin with the assistance of enzyme immunoassay (EIA), chromatography, and mass spectrometry techniques and this section is critically appraised in this publication. The principles for anion gap, osmol gap and lactate gap and their usage in intoxications is shown. Basic rules in test methodology and pre-analytics are reviewed. Biomarkers in general are presented in part one and biomarkers for specific intoxications including ethanol, paracetamol, cardiovascular drugs and many others are presented in part two of these publications.

Development and application of a forensic toxicological library for identification of 56 natural toxic substances by liquid chromatography–quadrupole time-of-flight mass spectrometry

Purpose

The present study aims to develop a forensic toxicological library to identify 56 natural toxic substances by liquid chromatography–quadrupole time-of-flight tandem mass spectrometry (LC–QTOF-MS/MS).

Methods

For setting up the library of product ion spectra, individual substances (31 plant toxins, 7 mushroom toxins, 5 marine toxins, 5 frog venoms, 4 mycotoxins, and 4 substances derived from plants) were analyzed by LC–QTOF-MS/MS with positive and negative ionization. The product ion spectra were acquired at the collision energies (CEs) of 20, 35, and 50 eV in single enhanced product ion mode and then in collision energy spread mode in which the CE ramp range was set to 35 ± 15 eV.

Results

To test the performance of the library, human blood plasma samples were spiked with a mixture of lycorine and domoic acid, extracted by acetonitrile deproteinization and analyzed by LC–QTOF-MS/MS. Identification by our library search could be achieved for these toxins at the purity scores of 79.1 and 67.2, respectively. The method was also applied to postmortem blood from a death case with an aconite intake, and showed that four toxins in an aconite could be identified in the blood sample at the purity scores of 54.6–60.3.

Conclusions

This library will be more effective for the screening of natural toxic substances in routine forensic toxicological analysis. To our knowledge, there are no reports dealing with development of library for natural toxic substances by LC–QTOF-MS/MS.

[Acute intoxications: markers for screening, diagnosis and therapy monitoring]

Acute poisonings account for a significant proportion of the patient population presenting to intensive care units, whereby mixed drug overdoses and prescription drug overdoses predominate. The aim of this article was to describe indications for screening, diagnosis and therapy monitoring in acute overdoses in the intensive care unit. To conduct this work, a literature search was carried out and a review was written based on guidelines, case reports, expert opinions and scientific publications. Toxidromes are a useful tool for classification of clinical characteristics when the causative agent is initially unknown. Especially in critical care medicine, identifying and quantifying of the causative toxin by enzyme immunoassays, chromatography and mass spectrometry should be attempted. Intensive care treatment of patients with acute overdoses includes not only monitoring and support of vital functions but also methods for primary and secondary elimination of toxins. The indication for the use of extracorporeal procedures should be carefully evaluated and the method should be chosen based on protein binding and molecular size. Lipid emulsion therapy, high-dose insulin euglycaemia therapy and hyperbaric oxygenation are also increasingly used.

High-throughput screening of toxic substances by extractive electrospray ionization mass spectrometry and their identification via databank construction

More than 200 toxic substances (including narcotic drugs, psychotropic drugs, organic phosphorus compounds, carbamates, pyrethroids and other pesticides, veterinary drugs, rodenticides, natural toxins, and other drugs) were identified and quantified using an ion-trap mass spectrometer. The advantages of this technique-its selectivity, accuracy, precision, utilization of only small amounts of the sample, and short analysis time for a single sample (less than 30s)-render it a rapid and accurate methodology for toxin screening. Subsequently, an extractive electrospray ionization (EESI) mass spectrometry database was established by combining the Xcalibur data processing system with NIST database software. This allowed unknown toxicants in urine and blood samples, stomach contents, and liver samples, as provided by the Jiangxi Provincial Public Security Department, to be analyzed and identified. This EESI methodology and databank has the potential for widespread application to the large-scale analysis of practical samples. Graphical abstract ᅟ.

Development of a high-throughput screening analysis for 288 drugs and poisons in human blood using Orbitrap technology with gas chromatography-high resolution accurate mass spectrometry

The screening analysis for drugs and poisons always symbolizes the capabilities of a forensic laboratory. Due to the rapid emergence of new compounds in clinical and forensic intoxication cases, sensitive and specific methods are necessary for the screening of wide range of target compounds. A novel high-throughput screening method has been developed for the toxicological analysis of 288 drugs and poisons in human blood using Orbitrap technology with gas chromatography-high resolution mass spectrometry (GC-HRMS). This method allows for the fast detection and identification of high-throughput forensically important drugs and poisons, e.g., drugs of abuse (cocaine, amphetamines, synthetic cannabinoids, opiates, hallucinogen), sedative-hypnotics, antidepressants, non-steroidal anti-inflammatory drugs, pesticides (acaricides, fungicides, insecticides, nematicides), and cardiovascular agents in one single GC-Q Exactive run. After a simple extraction with ethyl ether and buffer, following centrifugation, the supernatant was injected into the system. For detection, spiked blood samples were analyzed by Orbitrap-GC-HRMS using an electrospray ionization in full scan mode with a scan range from 40 to 650 (m/z). The identification of drugs and poisons in the samples was carried out by searching the accurate molecular mass of characteristic fragment ions, ion rations and retention time (RT) against the in-house library that we developed with 70 ev electron energy. The limit of detection (LOD) for most compounds (249 in a total of 288 compounds) was below 100 ng/mL. For selectivity, no substances have been identified in drug-free blood samples from six different sources, and the method was suitable for the recovery and the carryover. The coefficient of variation (CV) of the RTs was below 0.99% in all reproducibility experiments. Mass accuracy was always better than 3 ppm, corresponding to a maximum mass error of 1.04 millimass units (mmu). The developed method was applied to 136 real samples from forensic cases, demonstrating its suitability for the sensitive and fast screening of high-throughput drugs in human blood samples.

Diagnosis of Heroin Overdose in an 8-Year-Old Boy: Reliable Contribution of Toxicological Investigations

Toxicological investigations are often required by clinicians in comatose patients with suspected poisoning. However, the usefulness of toxicological analyses to support a diagnosis of acute poisoning is debated among clinicians and the interpretation of laboratory tests is challenging given the wide diversity of analytical techniques available. We report the case of an 8-year-old boy who was admitted to an intensive care unit with severe respiratory depression and neurological impairment. In order to formulate appropriate hypothesizes about the diagnosis and circumstances of intoxication, clinicians consulted toxicologists for a comprehensive toxicological screening. Routine blood immunoassays were negative for common toxicants but urine tests were positive for opiates. A general unknown screening using liquid and gas chromatography combined with mass spectrometry detection confirmed the presence of morphine, codeine and related glucuronides metabolites in plasma and urine. Subsequently, morphine and codeine were quantified in plasma samples by online-SPE-LC-MS-MS. In addition, analyses performed with GC-MS and LC-MSn identified compounds used as markers when profiling illicit heroin, namely noscapine, dextromethorphan and codeine. In conjunction with the patient's history, clinical picture and circumstances of intoxication, toxicological findings strongly suggested an acute pediatric opioid overdose as a collateral damage of parental heroin abuse in the home. This case highlights the significant contribution of toxicological investigations in sensitive legal cases and the critical role of communications between clinicians and toxicologists.

Liquid Chromatography-Tandem Mass Spectrometry: An Emerging Technology in the Toxicology Laboratory

In the last decade, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has seen enormous growth in routine toxicology laboratories. LC-MS/MS offers significant advantages over other traditional testing, such as immunoassay and gas chromatography-mass spectrometry methodologies. Major strengths of LC-MS/MS include improvement in specificity, flexibility, and sample throughput when compared with other technologies. Here, the basic principles of LC-MS/MS technology are reviewed, followed by advantages and disadvantages of this technology compared with other traditional techniques. In addition, toxicology applications of LC-MS/MS for simultaneous detection of large panels of analytes are presented.

Liquid chromatography-quadrupole-time-of-flight mass spectrometry screening procedure for urine samples in forensic casework compared to gas chromatography-mass spectrometry

This work represents the development, validation, and application of a liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) screening method for the detection of pharmaceutical substances and illicit drugs (acidic, basic, and neutral organic drugs) in urine samples. Time-of-flight mass spectrometry was performed using an LC-Triple TOF 5600 system with electrospray ionization operated in both positive and negative mode, respectively. The limits of detection (LODs), determined for 34 substances, were < 10 ng/mL for 91% of the compounds. The limits of quantitation (LOQs) were < 20 ng/mL for 91% of the substances. The identification of the compounds was based on exact mass (< ± 5 ppm), retention time (<2%) if available, isotopic pattern fit (<10%) and library hit (>70%). These four parameters served as identification criteria and are discussed according to their role in identifying compounds even without reference substances. In routine casework, two in-house XIC (extracted ion chromatogram) lists, consisting of 456 protonated and 26 deprotonated compounds were used and retention times for 365 compounds were available. Compared to the results found with the established gas chromatography-mass spectrometry (GC-MS) procedure, the findings with the LC-QTOF-MS screening method showed a good comparability. Results that were not detected by LC-QTOF-MS because of a missing entry in the targeted XIC list could retrospectively be confirmed by simply entering the elemental formula of the relevant substance into the software and reprocessing the sample. LC-QTOF-MS offers an attractive technique for the fast and specific identification of illicit drugs and toxic compounds in urine samples. Copyright © 2016 John Wiley & Sons, Ltd.

Recent developments in urinalysis of metabolites of new psychoactive substances using LC–MS

In the last decade, an ever-increasing number of new psychoactive substances (NPSs) have appeared on the recreational drug market. To account for this development, analytical toxicologists have to continuously adapt their methods to encompass the latest NPSs. Urine is the preferred biological matrix for screening analysis in different areas of analytical toxicology. However, the development of urinalysis procedures for NPSs is complicated by the fact that generally little or no information on urinary excretion patterns of such drugs exists when they first appear on the market. Metabolism studies are therefore a prerequisite in the development of urinalysis methods for NPSs. In this article, the literature on the urinalysis of NPS metabolites will be reviewed, focusing on articles published after 2008.

Modern analytical technologies for the detection of drug abuse and doping

Consequences to individuals convicted of abusing prohibited drugs or doping agents can be severe, including loss of employment, child custody, driving privileges, right to compete in international sports and ultimately freedom, when mandatory confinement occurs. In view of these penalties, laboratories charged with providing evidence must maximize testing accuracy. False positive and false negative tests are prevented by combining sensitive immunoassays and specific chromatographic-mass spectrometric detection. In addition, testing different biological matrices offers unique information about the drug-use history of an individual.:

Screening and confirmation methods for GHB determination in biological fluids

The purpose of this review is to provide a comprehensive overview of reported methods for screening and confirmation of the low-molecular-weight compound and drug of abuse gamma-hydroxybutyric acid (GHB) in biological fluids. The polarity of the compound, its endogenous presence, its rapid metabolism after ingestion, and its instability during storage (de novo formation and interconversion between GHB and its lactone form gamma-butyrolactone) are challenges for the analyst and for interpretation of a positive result. First, possible screening procedures for GHB are discussed, including colorimetric, enzymatic, and chromatography-based procedures. Confirmation methods for clinical and forensic cases mostly involve gas chromatography (coupled to mass spectrometry), although liquid chromatography and capillary zone electrophoresis have also been used. Before injection, sample-preparation techniques include (a combination of) liquid-liquid, solid-phase, or headspace extraction, and chemical modification of the polar compound. Also simple "dilute-and-shoot" may be sufficient for urine or serum. Advantages, limitations, and trends are discussed.

Rapid sample pre-treatment prior to GC-MS and GC-MS/MS urinary toxicological screening

Drug screening is an important issue in clinical and forensic toxicology. Gas chromatography coupled to mass spectrometry (GC-MS) remains the gold standard technique for the screening of unknown compounds in urine samples. However, this technique requires substantial sample preparation, which is time consuming. Moreover, some common drugs such as cannabis cannot be easily detected in urine using general procedures. In this work, a sample preparation protocol for treating 200 μL of urine in less than 30 min is described. The enzymatic hydrolysis of glucuro-conjugates was performed in 5 min thanks to the use of microwaves. The use of a deconvolution software allowed reducing the GC-MS run to 10 min, without impairing the quality of the compound identifications. Comparing the results from 139 authentic urine samples to those obtained using the current routine analysis indicated this method performed well. Moreover, additional 5-min GC-MS/MS programs are described, enabling a very sensitive target screening of 54 drugs, including THC-COOH or buprenorphine, without further sample preparation. These methods appeared as an interesting alternative to immuno-assays based screening. The analytical strategy presented in this article proved to be a promising approach for systematic toxicological analysis (STA) of drugs in urine.

How can analytical diagnostics in clinical toxicology be successfully performed today?

This article discusses current strategies for efficient analytical diagnostics in clinical toxicology. The tasks for such diagnostics, different analytical strategies and various methods were reviewed. They cover mainly gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry procedures for target or comprehensive screening for drugs (of abuse) and poisons, and for quantification in blood. Quality control aspects and strategies for competent interpretation of the analytical result in correlation with the clinical signs presented by the patient are discussed.

New cathinone-derived designer drugs 3-bromomethcathinone and 3-fluoromethcathinone: studies on their metabolism in rat urine and human liver microsomes using GC-MS and LC-high-resolution MS and their detectability in urine

3-Bromomethcathinone (3-BMC) and 3-Fluoromethcathinone (3-FMC) are two new designer drugs, which were seized in Israel during 2009 and had also appeared on the illicit drug market in Germany. These two compounds were sold via the Internet as so-called "bath salts" or "plant feeders." The aim of the present study was to identify for the first time the 3-BMC and 3-FMC Phase I and II metabolites in rat urine and human liver microsomes using GC-MS and LC-high-resolution MS (HR-MS) and to test for their detectability by established urine screening approaches using GC-MS or LC-MS. Furthermore, the human cytochrome-P450 (CYP) isoenzymes responsible for the main metabolic steps were studied to highlight possible risks of consumption due to drug-drug interaction or genetic variations. For the first aim, rat urine samples were extracted after and without enzymatic cleavage of conjugates. The metabolites were separated and identified by GC-MS and by LC-HR-MS. The main metabolic steps were N-demethylation, reduction of the keto group to the corresponding alcohol, hydroxylation of the aromatic system and combinations of these steps. The elemental composition of the metabolites identified by GC-MS could be confirmed by LC-HR-MS. Furthermore, corresponding Phase II metabolites were identified using the LC-HR-MS approach. For both compounds, detection in rat urine was possible within the authors' systematic toxicological analysis using both GC-MS and LC-MS(n) after a suspected recreational users dose. Following CYP enzyme kinetic studies, CYP2B6 was the most relevant enzyme for both the N-demethylation of 3-BMC and 3-FMC after in vitro-in vivo extrapolation.

Recent developments in MS for small molecules: application to human doping control analysis

Recent developments in MS for the detection of small molecules in the context of doping control analysis are reviewed. Doping control analysis is evolving together with MS, which is the technique of choice in order to accomplish the analytical requirements in this field. Since these analytical requirements for the detection of a doping agent depend on the substance, in the first section we review the different scenarios. The commonly established approaches, together with their achievements and drawbacks are described. New developments in hyphenated MS techniques (both GC–MS/MS and LC–MS/MS) concerning interfaces and analyzers are mentioned. The use (or potential use) of these developments in order to minimize the limitations of the commonly established approaches in the doping control field is discussed. Finally, a brief discussion about trends and remaining limitations is presented.