Application of ultrasound-assisted liquid-liquid microextraction coupled with gas chromatography and mass spectrometry for the rapid determination of synthetic cannabinoids and metabolites in biological samples.

The constant emergence of new psychoactive substances is a challenge to clinical and forensic toxicologists who need to constantly update analytical techniques to detect them. A large portion of these substances are synthetic cannabinoids. The aim of this study was to develop a rapid and simple method for the determination of synthetic cannabinoids and their metabolites in urine and blood using gas chromatography-mass spectrometry. The method involves an ultrasound-assisted dispersive liquid-liquid microextraction that implies a rapid procedure, giving excellent extraction efficiencies with minimal use of toxic solvents. This is followed by silylation and analysis with gas chromatography-mass spectrometry. The chromatographic method allows for the separation and identification of 29 selected synthetic cannabinoids and some metabolites. The method was validated on urine and blood samples with the ability to detect and quantify all analytes with satisfactory limits of detection (from 1 to 5 ng/mL), limits of quantification (5 ng/mL), and selectivity and linearity (in the range of 5-200 ng/mL). The developed assay is highly applicable to laboratories with limited instrumental availability, due to the use of efficient and low-cost sample preparation and instrumental equipment. The latter may contribute to enhance the detection of new psychoactive substances in clinical and forensic toxicology laboratories.

Rapid and simple procedure for the determination of cathinones, amphetamine-like stimulants and other new psychoactive substances in blood and urine by GC-MS.

In the last few years an increasing number of new psychoactive substances (NPS), with different chemical structures (of which 37% are stimulants), have been released into the illicit drug market. Their detection and identification in biological samples is hence of great concern. The aim of this work was to develop a high-throughput and rapid method for the determination of different classes of stimulants (amphetamine-type stimulants, cathinones, phenethylamines and ketamine analogues) from blood and urine samples using GC-MS. The proposed method allows the almost simultaneous derivatization and extraction of analytes from biological samples in a very short time, by using hexyl chloroformate as derivatization agent. The extraction of analytes was performed by Dispersive Liquid Liquid Microextraction (DLLME), a very rapid, cheap and efficient extraction technique that employs microliter amounts of organic solvents. The chromatographic method allowed for the separation of 26 stimulants including positional isomers (3-MMC and 4-MMC). The method was validated on urine and blood samples with the ability to detect and quantify all analytes with satisfactory limits of detection (LODs) ranging between 1 and 10ng/mL, limits of quantification (LOQs) between 2 and 50ng/mL, selectivity and linearity (5-1000ng/mL). The method was then applied to real samples from forensic cases, demonstrating its suitability for the screening of a wide number of stimulants in biological specimens.

A case of tri-allelic pattern at locus D3S1358 on chromosome 3p21 inherited from paternal grandmother.

We are reporting a case of tri-allelic inheritance at locus D3S1358 commonly used for genetic identification in forensic DNA testing. This case was encountered during routine paternity testing using commercial DNA profiling kits. The tri-allelic inheritance identified was probably a result of duplication at this locus, supported by the equal peak intensities and inheritance pattern from grandparent to child.