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 LC-MS/MS confirmation method for the determination of 17 drugs of abuse in oral fluid and its application to real samples.

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmation method for the direct analysis of 17 drugs starting from 200µL of diluted oral fluid (OF), in a single chromatographic run, was developed and validated. Cocaine, benzoylecgonine (BEG), cocaethylene, Δ-9-tetrahydrocannabinol (Δ-9-THC), buprenorphine, 6-acetylmorphine (6AM), morphine, codeine, methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), methylenedioxyamphetamine (MDA), 3,4-Methylenedioxy-N-ethylamphetamine (MDE), ketamine, N-methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (MBDB) were determined in a chromatographic run of 12min only with no sample pre-treatment, after the addition of 15 different internal standards (ISs). The method met all requirements in terms of linearity, accuracy (precision and trueness), recovery, and stability requested by FDA guidelines. Carry-over and interferences were negligible, as well as the matrix effects. LLOQs are below the limits defined by European guidelines and Italian national laws. The original oral fluid collections are stable at least six months at -20°C and one week at +4°C.

Ethanol Determination in Post-Mortem Samples: Correlation between Blood and Vitreous Humor Concentration.

Ethanol (ethylic alcohol) represents the most commonly used drug worldwide and is often involved in clinical and forensic toxicology. Based on several reports, excessive alcohol consumption is the main contributing factor in traffic accidents, drownings, suicides, and other crimes. For these reasons, it becomes essential to analyze the alcohol concentration during autopsy. Although blood is usually used for alcohol analysis in post-mortem cases, it could suffer alterations, putrefaction, and microbial contaminations. As an alternative to whole blood, vitreous humor has been successfully used in medico-legal studies. In this work, post-mortem specimens were analyzed for ethanol determination. The analysis of blood and vitreous humor were carried-out using gas chromatography-flame ionized detector (GC-FID) with a total run time of 6 min. The method was validated in terms of limit of detection, limit of quantification, dynamic range, sensibility, recovery, precision and trueness. A linear regression analysis indicated a coefficient of determination (R2) of 0.9981. The study confirmed no statistically differences between alcohol concentration in blood and vitreous humor, leading vitreous humor as an excellent matrix that could be used as an alternative to whole blood in toxicological analysis in cases where blood is not available.

Novel MIPs-Parabens based SPE Stationary Phases Characterization and Application.

In this work, the synthesis, characterization, and application of novel parabens imprinted polymers as highly selective solid-phase extraction (SPE) sorbents have been reported. The imprinted polymers were created using sol-gel molecular imprinting process. All the seven parabens were considered herein in order to check the phase selectivity. By means of a validated HPLC-photodiode array detector (PDA) method all seven parabens were resolved in a single chromatographic run of 25 min. These SPE sorbents, in-house packed in SPE empty cartridges, were first characterized in terms of extraction capability, breakthrough volume, retention volume, hold-up volume, number of theoretical plates, and retention factor. Finally, the device was applied to a real urine sample to check the method feasibility on a very complex matrix. The new paraben imprinted SPE sorbents, not yet present in the literature, potentially encourage the development of novel molecularly imprinted polymers (MIPs) to enhance the extraction efficiency, and consequently the overall analytical performances, when the trace quantification is required.