Development of a New LC-MS/MS Screening Method for Detection of 120 NPS and 43 Drugs in Blood

A broad-spectrum LC-MS/MS method for screening and quantification of 100 analytes in clinical and autopsy blood samples

Liquid chromatography coupled with mass spectrometry (LC-MS) has been tremendously used for screening purposes in forensic toxicology, because of their great adaptability and reasonable time/resource consumption. Herein, a fully validated method based on liquid-liquid extraction (LLE) in human whole blood, by a multiple reaction monitoring (MRM) analysis through LC-MS/MS, is described. The proposed method simultaneously detects 100 analytes (plus three deuterated internal standard compounds) belonging to many different classes, including drugs of abuse, prescription and over-the-counter drugs commonly involved in poisoning and medical malpractice cases in our territory, as well as certain new psychoactive substances (NPS) and toxic substances potentially associated with adverse effects. The optimised LLE employs one extraction step of 200 μL blood using 0.1 M HCl methyl-tert-butyl-ether (MTBE) (acidified with concentrated HCl) proved to be suitable for the extraction of basic and neutral substances; as a reconstitution solvent a mixture of 88:12v/v, 0.1 % formic acid in 10 mM aqueous ammonium acetate, pH 3.5: 0.1 % formic acid in acetonitrile was used, yielding satisfactory recoveries for all analytes. The method was sensitive, showing low LOD/ LOQ for all substances ranging from 0.01 to 5/ 0.05-20 ng/mL, respectively. Linearity ranged between 0.05-500 ng/mL (R2 = 0.9811-0.9995), and the inter- and intra-day precisions ranged between 3-15 % and 7-18 %, respectively. Accuracy was evaluated in terms of percentage recovery, lying within acceptable range. The matrix effect expressed as ion suppression/enhancement of each analyte was in the range ±25 % for all analytes. Post-preparative stability of analytes was higher than 85 %, while no carryover between runs was observed. The developed method has been successfully applied in routine toxicological analyses for the analysis of biological samples from clinical and autopsy cases.

Analyte protectant approach to protect amide-based synthetic cannabinoids from degradation and esterification during GC-MS analysis

The forensic analysis of amide-based synthetic cannabinoids (SCs) in seized materials is routinely performed using gas chromatography-mass spectrometry (GC-MS); however, a major challenge associated with GC-MS is the thermolytic degradation of substances with sensitive functional groups. Herein, we report the comprehensive thermal degradation and ester transformation of amide-based SCs, such as AB-FUBINACA, AB-CHMINACA, and MAB-CHMINACA, during GC-MS analysis and their treatment with analyte protectants (APs). These SCs were found to undergo thermolytic degradation during GC-MS in the presence of non-alcohol solvents. Using methanol as an injection solvent resulted in the conversion of the amide group to an ester group, producing other SCs such as AMB-FUBINACA, MA-CHMINACA, and MDMB-CHMINACA. Degradant and ester product formation has been interpreted as the adsorption of target SCs on glass wool via hydrogen bonding interactions between the active silanol and amide groups of the SCs, followed by an addition and/or elimination process. The factors found to influence the thermal degradation and/or esterification of the amide functional group include residence time, activity of glass wool, and injection volume. This report presents the fragmentation patterns of all compounds that were produced by degradation and esterification. Using 0.5 % sorbitol (AP) in MeOH as an injection solvent resulted in complete protection and improvement of the chromatographic shape of the compounds. This method has been successfully confirmed in terms of sensitivity, linearity, accuracy, and precision for standard solutions and tablet extraction using 0.5 % sorbitol in MeOH. Using AP increased the sensitivity by ten times or more compared to the use of only MeOH. The limit of detection for all analytes was determined as 25 ng/mL, and the calibration curves were linear over the concentration range of 50-2000 ng/mL. The values of accuracy error were below 11 %, and precision was less than 13 %. The effects of phytochemicals of herbal products, tablet ingredients, and biological matrices on the degradation and/or esterification and APs performance have also been evaluated in this work.

Target and suspect screening of psychoactive substances in seizures and oral fluid exploiting retention time prediction and LC-MS/MS analysis

BACKGROUND

Novel psychoactive substances (NPS) are a group of substances, mainly of synthetic origin, characterized by toxicological properties extremely dangerous. The main difficulty in recognizing NPS in seizures and biological samples lies in their dynamic nature, related to the continuous synthesis and introduction on the market of new drugs, often with very similar structures to existing ones. The aim of this study was the creation of a robust and versatile method for the analysis of traditional drugs and NPS in different matrices.

RESULTS

Both target analysis and suspect screening methodologies were developed. The strategy used for suspect screening allowed to collect data through a scheduled multi reaction monitoring (sMRM) survey which triggered the collection of enhanced product ion (EPI) spectra when a compound met information dependent acquisition (IDA) criteria. The retention time of the different drugs, which was crucial to define the sMRM survey scan parameters, was predicted with a Quantitative Structure Retention (Chromatographic) Relationship (QSRR) model by Multiple Linear Regression. The model was validated through the evaluation of training set predictions, an external validation set and a leave-one out strategy; the results showed that the method fit for its purpose. The target method was validated in oral fluid as a testing matrix, with excellent results in term of recovery, accuracy, precision and matrix effect. Finally, the performances of the suspect method were evaluated by analysing a mixture containing 8 reference standards not included in the initial dataset, as well as seizures and real oral fluid samples. Four NPS were putatively identified in the analysed samples.

SIGNIFICANCE

The advantage of the proposed approach is the possibility of quantifying 65 classical drugs of abuse and NPS and, at the same time, detect and putatively identify 146 additional drugs in one single LC-MS/MS run. This is an innovative strategy for multi analyte detection and enables detection of low concentrations of drugs in complex biological matrices such as oral fluid. Considering the highly dynamic drug market, a strength of this strategy is that the analytical method can be kept up to date through the addition of new compounds based on the last drug monitoring bodies alerts without the need of authentic standards.

Clinical manifestations and analytical reports for MDPHP acute intoxication cases

MDPHP is a synthetic cathinone (SC) belonging to α-pyrrolidinophenone derivatives. It is a central nervous system stimulant and may induce hallucinations, paranoia, tachycardia, hypertension, chest pain, and rhabdomyolysis. In literature, a few cases of intoxication have been reported. In the present study, 17 cases of MDPHP intake were described including the analytical findings and clinical manifestations. MDPHP was quantified by liquid chromatography-tandem mass spectrometry in blood (range 1.26-73.30 ng/mL) and urine (range 19.31-8769.64 ng/mL) samples. In three cases the presence of α-PHP was observed. In one case, MDPHP was the only detected substance. Concomitant use of MDPHP with other substances, particularly psychostimulants, was common and it was difficult to describe the peculiar clinical characteristics of this SC. Most of the symptoms overlapped those expected, some of them were unusual and all of them particularly severe thus inducing the research of NPS in laboratory tests. We demonstrated the presence of psychiatric, neurological, and respiratory symptoms, as well as the possible presence of rhabdomyolysis and cardiotoxicity associated with the use of MDPHP. ED admissions were also more frequent in patients with addiction problems. In some cases, MDPHP intake required intensive supportive care. A multidisciplinary approach, including specialist consultation, is recommended for patients showing challenging features. Moreover, we demonstrated that the adoption of advanced analytical techniques, i.e., liquid chromatography-tandem mass spectrometry, is necessary to detect these molecules. Further studies are needed to understand MDPHP intake patterns and associated symptoms. It is essential to raise awareness in addiction treatment centers and among potential users, especially young people, and chemsex addicted.

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

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

LC-MS/MS Application in Pharmacotoxicological Field: Current State and New Applications

Nowadays, it is vital to have new, complete, and rapid methods to screen and follow pharmacotoxicological and forensic cases. In this context, an important role is undoubtedly played by liquid chromatography-tandem mass spectrometry (LC-MS/MS) thanks to its advanced features. This instrument configuration can offer comprehensive and complete analysis and is a very potent analytical tool in the hands of analysts for the correct identification and quantification of analytes. The present review paper discusses the applications of LC-MS/MS in pharmacotoxicological cases because it is impossible to ignore the importance of this powerful instrument for the rapid development of pharmacological and forensic advanced research in recent years. On one hand, pharmacology is fundamental for drug monitoring and helping people to find the so-called "personal therapy" or "personalized therapy". On the other hand, toxicological and forensic LC-MS/MS represents the most critical instrument configuration applied to the screening and research of drugs and illicit drugs, giving critical support to law enforcement. Often the two areas are stackable, and for this reason, many methods include analytes attributable to both fields of application. In this manuscript, drugs and illicit drugs were divided in separate sections, with particular attention paid in the first section to therapeutic drug monitoring (TDM) and clinical approaches with a focus on central nervous system (CNS). The second section is focused on the methods developed in recent years for the determination of illicit drugs, often in combination with CNS drugs. All references considered herein cover the last 3 years, except for some specific and peculiar applications for which some more dated but still recent articles have been considered.

A New Multi-Analyte LC-MS-MS Screening Method for the Detection of 120 NPSs and 49 Drugs in Hair

Liquid chromatography coupled with mass spectrometry (LC-MS) has been increasingly used for screening purposes in forensic toxicology. High versatility and low time/resource consumption are the main advantages of this technology. Numerous multi-analyte methods have been validated in order to face the analytical challenge of new psychoactive substances (NPSs). However, forensic toxicologists must focus the attention also on "classical" NPSs and medicines, such as benzodiazepines (BDZs) and prescription opioids. In this paper, a new method for the simultaneous detection of 169 substances (120 NPSs and 49 other drugs) in hair by LC-MS-MS is described. After the decontamination of hair samples with dichloromethane, a 20-mg aliquot of the sample was mixed with 1 mL of methanol (MeOH; 0.1% of formic acid) and then sonicated at room temperature for 2 h. The mixture was then dried under nitrogen stream and reconstituted with 100 µL of MeOH. LC separation was achieved with a 100-mm-long C18 column in 35 min, and mass acquisition was performed in dynamic multiple reaction monitoring mode and in positive ionization. The analysis results were very sensitive, with the limit of quantification ranging from 0.07 to 10.0 pg/mg. Accuracy and precision were always within the acceptable criteria. Matrix effect and recovery rate ranges were from -21.3 to + 21.9% and from 75.0 to 99.3%, respectively. The new method was successfully applied in a preliminary study on the prevalence of NPSs, BDZs and other substances in case of driving license issuance. In 14% of cases, BDZs/antidepressants (mainly trazodone, diazepam/nordiazepam and flunitrazepam) were found. Codeine, ketamine, methylone and mephedrone were also detected.

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

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

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.