Development of a micro-solid-phase extraction molecularly imprinted polymer technique for synthetic cannabinoids assessment in urine followed by liquid chromatography–tandem mass spectrometry

Several molecularly imprinted polymers (MIPs) have been synthesized for the first time using various synthetic cannabinoids (JWH007, JWH015 and JWH098) as template molecules. Ethylene dimethacrylate (EDMA) was used as a functional monomer for all cases. Similarly, divinylbenzene (DVB) and 2,2′-azobisisobutyronitrile (AIBN) were used as cross-linker and initiator, respectively. The prepared MIPs have been fully characterized and evaluated as new selective adsorbents for micro-solid phase extraction (μ-SPE) of synthetic cannabinoids in urine. The developed MIP-μ-SPE devices consisted of a polypropylene (PP) porous membrane containing the adsorbent (novel porous membrane protected micro-solid phase extraction based on a cone-shaped device) for operating in batch mode, which allowed a fast and integrated extraction-cleanup procedure. High performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) was used for quantifying the analytes after MIP-μ-SPE. The best performances were obtained for MIPs prepared from JWH015 as a template. Optimum loading conditions were found to be urine pH of 5.0 and adsorption time of 8.0 min under mechanical (orbital-horizontal) stirring at 100 rpm. The composition of the eluting solution consisted of 75:20:5 heptane/2-propanol/ammonium hydroxide. The elution was assisted by ultrasounds (37 kHz, 325 W) for 8.0 min. In addition, studies regarding selectivity have also been addressed for several drugs of abuse under optimized loading/adsorption conditions. Validation of the method showed good precision and analytical recovery by intra-day and inter-day assays (RSD values lower than 7 and 10% for intra-day and inter-day precision, and within the 83–100% range for intra-day and inter-day analytical recovery)

Statistical analysis of toxicological data of victims of traffic accidents in Galicia (Spain)

Driving under the influence of alcohol or drugs is a very common behavior in our environment and a serious problem for public health. On the one hand, in 2016, 400,000 people died in the world in traffic accidents in which ethanol was involved. On the other hand, traffic accidents in which the use of drugs of abuse other than ethyl alcohol accounted for more than 160,000 deaths worldwide in 2017. The objective of this work is to carry out a review of the 710 cases of people who died in traffic accidents received at the forensic toxicology service of the Institute of Forensic Sciences of the University of Santiago de Compostela (Galicia-Spain) over a period of 10 years (2009–2019). We performed an observational study of period prevalence, in which the following data were collected: age, sex, year, and analytical results in plasma, in the case of being positive. The data collected was subjected to statistical treatment. Of the 710 cases analyzed, 123 correspond to pedestrians and 587 to occupants of vehicles or motorcycles. A total of 77.6% of the deceased were men. At least one psychotropic substance was found in the blood of almost 40% of the victims. The most frequently found substance was ethyl alcohol, which appeared in 231 cases, more frequently in males. The second place is occupied by benzodiazepines, which appeared in 43 cases, followed by cocaine, which was detected in 25 cases. Polydrug use was found in only 44 cases, with the association of ethanol and cocaine being the most commonly found, followed by that of ethanol and benzodiazepines. Only in 5 of the cases analyzed there were 3 or more substances present. With the data obtained in this study, it is shown that in traffic accidents, the finding of different toxic or medicinal substances is frequent. Ethyl alcohol continues to be very present in road accidents (most detected substance), with the great impact that this implies. Secondly, the presence of benzodiazepines stands out, and cocaine is the third most detected toxic in this study. These results allow to obtain a profile of the substances most frequently involved in traffic accidents. Despite the surveillance, control, and information campaigns that the Spanish Government regularly carries out, the results are far from satisfactoryOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer NatureS

Las drogas en Galicia

Las drogas de abuso han sido consumidas desde los tiempos más remotos, siendo en aquel enton­ ces su uso muy restringido, por la poca disponibilidad de las mismas, a rituales místico-religiosos y a tratamiento de algunas enfermedades. Con la revolución industrial en el siglo XIX, los labora­ torios farmacéuticos extraen los principios activos de las plantas y sintetizan sus derivados, pasan­ do a ser consumidas en mayor escala. La década de los sesenta fue marcada por el aumento espectacular en el consumo de estas sustan­ cias, pero especialmente en grupos sociales concretos y dentro de una revolución contracultural. Con el paso de los años se difundió a todos los estratos sociales, y con edades de inicio en el con­ sumo cada vez más precoces. En las últimas décadas la heroína fue uno de los principales temas de preocupación con respecto al mundo de las drogas que afectaba, fundamentalmente, a una población marginal; pero hoy los patrones de consumo han variado. Los jóvenes son protagonistas de consumos excesivos de alco­ hol, cannabis, cocaína y drogas de síntesis, todos ellos con fines recreativos en contextos lúdicos, de los cuales se derivan numerosas consecuencias que afectan, no sólo a la salud del individuo, sino también al entorno en que se desenvuelve y a la propia sociedad. Describiremos pues de forma resumida las características de las principales drogas, ya sean lega­ les o ilegales, de uso más extendido, haciendo especial hincapié en aquellas que a día de hoy son consumidas por mayor número de personas y por tanto con mayores consecuencias negativas

Synthetic cathinones determination by liquid chromatography-mass spectrometry after ultrasound membrane assisted extraction

The extraction time for membrane-assisted solvent extraction (MASE) when isolating synthetic cathinones from urine has been speeded up to 30 min by using ultrasounds. Separation and determination of eleven synthetic cathinones was further performed liquid chromatography-tandem mass spectrometry (LC-MS/MS). The ultrasound assisted MASE consisted of adjusting 5.0 mL of urine at pH 11.8 and performing the extractive process with 400 μL of n-hexane as an acceptor phase inside the polypropylene membrane under ultrasonication at room temperature. Synthetic cathinones exhibiting LogP values higher than 2.0, such as 3,4-dimethyl methcathinone, methylendioxypyrovalerone, and naphyrone), were efficiently extracted and pre-concentrated. Other synthetic cathinones (LogP between 2.0 and 0.7) were found to exhibit a lower mass transfer. The method was found to be matrix dependent, and a matrix-matched calibration was required for measurements. The achieved limits of detection (LOD) were between 0.03 (flephedrone) to 0.29 (ethylone) µg L-1, with relative standard deviations (RSDs) within the 6–14% and 7–19% ranges for intraday and inter-day assays, and intraday and inter-day analytical recoveries from 84 to 115% and 85 to 118%, respectively. The developed method was finally applied to urine samples from volunteers attending a music festivalThis work was supported by the Dirección Xeral de I + D – Xunta de Galicia Grupos de Referencia Competitiva (project number ED431C 2022/029)S

Exploring the Chelating Potential of an Easily Synthesized Schiff Base for Copper Sensing

The present study deals with the investigation of Cu2+, Ni2+ and Pd2+ chelating potential of the Schiff base, (E)-N-(2-((2-hydroxybenzylidene)amino)benzyl)-4-methylbenzenesulfonamide (H2SB). Crystal structures of Ni(HSB)2, Pd(HSB)2 and Cu(HSB)2 have been elucidated from single crystal X-ray diffraction data. NMR spectroscopy showed the presence of two conformers of Pd(HSB)2 in solution, both with an E configuration of the ligand. The determination of binding constants by fluorescence quenching showed that affinity of H2SB to Cu2+ in solution is higher than for Ni2+ and Pd2+. Since there is a high demand for selective, sensitive, rapid and simple methods to detect copper in aqueous samples (both as Cu2+ ions and as CuO NPs), we have explored H2SB as an optical chemosensor. H2SB interacts with increasing concentrations of Cu2+ ions, giving rise to a linear increase in the absorbance of a band centered at about 392 nm. H2SB displays a high selectivity toward Cu2+, even in the presence of the most common metal ions in water (Ca2+, Mg2+, Na+, K+, Al3+ and Fe3+), and some heavy transition metal ions such as the soft acids Pd2+ and Cd2+. H2SB also interacts with increasing concentrations of CuO NPs, which gives rise to a linear decrease in its fluorescence intensity (λem = 500 nm, λex = 390 nm). Quenching has occurred as a result of the formation of a non-fluorescent ground-state surface complex H2SB–CuO NPs. The limits of detection and quantification of CuO NPs were 9.8 mg/L and 32.6 mg/L, respectively. The presence of TiO2, Ag and Au NPs does not interfere with the determination of CuO NPsThis research was funded by the Ministerio de Ciencia, Innovación y Universidades of Spain and Unión Europea (Fondo europeo de desarrollo regional) Ref. RTI2018-099222-B-I00; Dirección Xeral de I+D-Xunta de Galicia, Grupos de Referencia Competitiva (Ref. ED431C2018/19) and Strategic Grouping in Materials AEMAT (ED431 E2018/0)S

Determination of Topiramate and Carbamazepine in Plasma by Combined Dispersive Liquid–Liquid Microextraction and Gas Chromatography–Mass Spectrometry

Dispersive liquid–liquid microextraction, an environmentally friendly extraction technique, followed by gas chromatography–mass spectrometry operating in selected ion monitoring (SIM) mode, is here presented for the simultaneous determination of two anticonvulsant drugs in plasma, Topiramate and Carbamazepine. Experimental parameters affecting the recovery of the proposed extraction method, such as the extraction and dispersion solvent, the extraction and dispersion volume, the sample amount, the pH of the aqueous phase, the ultrasound time, the centrifugation time and ionic strength, were investigated. The limits of detection for Topiramate and Carbamazepine were 0.01 and 0.025 µg mL−1, and the limits of quantification were 0.025 µg mL−1 and 0.05 µg mL−1, respectively. The method is shown to be selective, accurate, precise and linear over the concentration ranges of 0.025–8 µg mL−1 for Topiramate and 0.05–3 µg mL−1 for Carbamazepine. The extraction recovery of the analytes ranged from 91.5% to 113.9%. The analytical method was successfully applied to real plasma samples received by the Forensic Toxicology Service of the Forensic Science Institute of Santiago de Compostela

Determination of seven antidepressants in pericardial fluid by means of dispersive liquid–liquid microextraction and gas chromatography–mass spectrometry

Although blood is often used to detect and quantify the presence of drugs, there are some instances where samples obtained from other biological matrices, like pericardial fluid (PF), are necessary since adequate blood samples may not be available. PF is an epicardial transudate, which contains plasma components that include toxicological substances making this sample useful when blood samples are not available. This fluid is a well-preserved postmortem sample and can easily be collected in larger amounts without significant contamination, compared with other body fluids. Although studies involving PF began around the 1980s, the adequacy of such fluid as a biological matrix has been poorly investigated. Antidepressants are frequently detected in postmortem samples from forensic cases. Nowadays, they constitute some of the most commonly prescribed drugs worldwide. A total of seven antidepressants (venlafaxine, mirtazapine, olanzapine, paroxetine, sertraline, fluoxetine and citalopram) were evaluated in this study. A new extraction method involving dispersive liquid–liquid microextraction (DLLME) is presented in which chloroform and acetonitrile are determined to be the best extraction and dispersing solvents. The experimental design was achieved using StatGraphics 18. The response surface methodology enabled us to know the optimal volume for the two solvents used in the DLLME. The detection technique used was gas chromatography–mass spectrometry with electron impact ionization as ionization source. A temperature gradient has been used and the total chromatographic separation time was 19.43 min. Validation results met the international validation guidance (Food and Drug Administration (FDA)). Under the optimal condition, the method offered good validation parameters showing a new efficient, simple, rapid and sensitive method. The analytical method was applied to 31 PF samples. Twenty-one samples were positive with concentrations between 0.19 and 8.48 µg/mL. Venlafaxine and olanzapine were the antidepressants most frequently foundS

Simple Method for the Determination of THC and THC-COOH in Human Postmortem Blood Samples by Gas Chromatography—Mass Spectrometry

A simple and sensitive analytical method was developed for qualitative and quantitative analysis of Δ9-tetrahydrocannabinol (Δ9-THC) and its metabolite 11-nor-Δ9-tetrahydrocannabinol-carboxylic acid (Δ9-THC-COOH) in human postmortem blood using gas chromatography/mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. The method involved a liquid-liquid extraction in two steps, one for Δ9-THC and a second one for Δ9-THC-COOH. The first extract was analyzed using Δ9-THC-D3 as internal standard. The second extract was derivatized and analyzed using Δ9-THC-COOH-D3 as internal standard. The method was shown to be very simple, rapid, and sensitive. The method was validated for the two compounds, including linearity (range 0.05–1.5 µg/mL for Δ9-THC and 0.08–1.5 µg/mL for Δ9-THC-COOH), and the main precision parameters. It was linear for both analytes, with quadratic regression of calibration curves always higher than 0.99. The coefficients of variation were less than 15%. Extraction recoveries were superior to 80% for both compounds. The developed method was used to analyze 41 real plasma samples obtained from the Forensic Toxicology Service of the Institute of Forensic Sciences of Santiago de Compostela (Spain) from cases in which the use of cannabis was involved, demonstrating the usefulness of the proposed method

Immobilization on Cellulose Paper of a Chemosensor for CdSe-Cys QDs

The Schiff base ligand H2SB derived from the condensation of N-(2-aminobenzyl)-5-(dimethylamino)naphthalene-1-sulfonamide with 4-formyl-3-hydroxybenzoic acid has been investigated as a chemosensor for the detection of CdSe-Cys QDs in water samples. We immobilized H2SB onto cellulose paper by forming an amide bond, which results from the condensation of a carboxylic acid and an amine. Three dominant signals located around 270, 330, and 420 nm in the diffuse reflectance spectrum of the H2SB-modified paper demonstrated its immobilization. A linear decrease can be observed in the absorbance of the 270 nm band with the increase of the CdSe-Cys QDs concentration from 100 ppb to 2 ppm. The LOD and LOQ show values of 245 and 815 ppb, respectively. An interaction via metal–ligand coordination between CdSe-Cys QDs and H2SB has been demonstrated with 1H NMR, ATR-FTIR, and UV-Vis spectroscopy