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The ongoing development of more and more new psychoactive substances continues to be a huge problem in 2022 affecting the European and international drug market. Through slight alterations in the structure of illicit drugs, a way to circumvent the law is created, as the created derivatives serve as legal alternatives with similar effects. A common way of structure modification is the induction of a halogen residue. Recently, halogenated derivatives of the well-known designer drug 4-methylaminorex appeared on the market and are available in various online shops. In this study, three novel halogenated 4-methylaminorex derivatives, namely 4′-fluoro-4-methylaminorex, 4′-chloro-4-methylaminorex, and 4′-bromo-4-methylaminorex, were purchased online and characterized using nuclear magnetic resonance (NMR) spectroscopy, liquid chromatography-high-resolution mass spectrometry (LC-HRMS), and chiral high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These derivatives possess two stereogenic centers, and analyses revealed that all of them were present as a racemic mixture of the trans diastereomeric form.

Besides the well-known hallucinogenic ketamine, various novel ketamine derivatives are available on the illicit drug market, sold as designer drugs. Minor chemical changes to the parent compound aim to circumvent existing narcotic drug laws while mimicking the effects of the original substance. Ketamine and some of its derivatives possess a chiral centre and therefore exist as two enantiomers. While differences in the effects of S- and R-ketamine are well studied, this is not the case for ketamine derivatives. Therefore, the development and adaptation of suitable enantioseparation methods for those compounds is important to face the problems of the constantly changing drug market. In this study, different chiral separation methods for capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) were tested on 11 ketamine derivatives. Some of them were enantioseparated for the first time due to their novelty. All compounds were at least partially separated on both instruments. HPLC separations were conducted using four different polysaccharide-based chiral stationary phases. Furthermore, an optical rotation detector coupled to the HPLC enabled the determination of the enantiomer elution order. In CE analysis, enantioseparation was achieved using 2% (w/v) acetyl-β-cyclodextrin or carboxymethyl- β-cyclodextrin in 10 mM di-sodium hydrogen phosphate as the background electrolyte in capillary electrophoresis.

This study aimed to design a hybrid oral liposomal delivery system for selenium nanoparticles (Lip-SeNPs) to improve the bioavailability of selenium. Thiolated chitosan, a multifunctional polymer with mucoadhesive properties, was used for surface functionalization of Lip-SeNPs. Selenium nanoparticle (SeNP)-loaded liposomes were manufactured by a single step microfluidics-assisted chemical reduction and assembling process. Subsequently, chitosan-N-acetylcysteine was covalently conjugated to the preformed Lip-SeNPs. The Lip-SeNPs were characterized in terms of composition, morphology, size, zeta potential, lipid organization, loading efficiency and radical scavenging activity. A co-culture system (Caco-2:HT29-MTX) that integrates mucus secreting and enterocyte-like cell types was used as a model of the human intestinal epithelium to determine adsorption, mucus penetration, release and transport properties of Lip-SeNPs in vitro. Thiolated Lip-SeNPs were positively charged with an average size of about 250 nm. Thiolated Lip-SeNPs tightly adhered to the mucus layer without penetrating the enterocytes. This finding was consistent with ex vivo adsorption studies using freshly excised porcine small intestinal tissues. Due to the improved mucoadhesion and retention in a simulated microenvironment of the small intestine, thiolated Lip-SeNPs might be a promising tool for oral selenium delivery.

Synthetic cathinones belong to one of the biggest and most popular classes of New Psychoactive Substances. Each year, new derivatives appear on the drug market, traded under various labels like “bath salts” or “legal highs”. In recent years, the emergence of new cathinone derivatives, containing a cyclohexyl residue, has been observed. Since 2021, threads about N-cyclohexylmethylone have been posted in various user forums. A powder sample of N-cyclohexylmethylone purchased by a client was collected in Austria in a local drug checking program and analyzed by GC-MS, LC-HRMS NMR spectroscopy and chiral HPLC. The aim of this study was to provide experimental NMR data of the compound and to determine the chiral status of the sample. Usually, cathinone derivatives are sold as racemic mixtures on the market. Investigation showed that in the sample both enantiomers were present. [Display omitted] •A new methylone derivative was analyzed with GC-MS, LC-HRMS and NMR spectroscopy.•It was identified as N-cyclohexylmethylone.•Chiral HPLC was used to determine, if the sample was sold as racemic mixture.•Both enantiomers were present in the sample.

The misuse of so called novel psychoactive substances is still a challenging problem worldwide. A special attribute of a lot of these compounds is a chiral centre enabling two possible enantiomers probably related to different pharmacological and toxicological properties. The goal of the present study was to present a simple and isocratic HPLC–UV method for enantioseparation of mainly cathinone and pyrovalerone derivatives as well as selected representatives of amphetamines, ketamines, benzofuries, phenidines, phenidates, morpholines and thiophenes. A Waters Acquity UPC2® Trefoil™ CEL1 2.5 µm, 3.0 × 150 mm column served as chiral stationary phase by means of cellulose tris-(3,5-dimethylphenylcarbamate) as chiral selector. Mobile phases consisted either of n-hexane/n-butanol/diethylamine (100:0.3:0.2) or n-hexane/diethylamine (100:0.2). The method was found to be applicable for rapid simultaneous chiral separations of cathinone derivatives, to determine enantiomeric elution orders, to detect positional isomers and to identify real-life samples. Also, a repeatability study was performed successfully. 78 out of 95 compounds were separated in their enantiomers successfully, 51 of them within 6 min. It was shown that all NPS bought from online vendors or seized by police were traded as racemic mixtures.

Fluctuation X-ray scattering (FXS) is an emerging experimental technique in which solution scattering data are collected using X-ray exposures below rotational diffusion times, resulting in angularly anisotropic X-ray snapshots that provide several orders of magnitude more information than traditional solution scattering data. Such experiments can be performed using the ultrashort X-ray pulses provided by a free-electron laser source, allowing one to collect a large number of diffraction patterns in a relatively short time. Here, we describe a test data set for FXS, obtained at the Linac Coherent Light Source, consisting of close to 100 000 multi-particle diffraction patterns originating from approximately 50 to 200 Paramecium Bursaria Chlorella virus particles per snapshot. In addition to the raw data, a selection of high-quality pre-processed diffraction patterns and a reference SAXS profile are provided.

We report photometric observations of Comet 103P/Hartley 2 during its 2023 apparition. Our campaign, conducted from August through December 2023, combined data from a global network of citizen astronomers coordinated by Unistellar and the Association Française d'Astronomie. Photometry was derived using an automated pipeline for eVscope observations in partnership with the SETI Institute and aperture photometry via AstroLab Stellar. We find that the comet's peak reduced brightness, measured at \\(G_ min = 10.24 0.47\\), continues a long-term fading trend since 1991. The decline in activity follows a per-apparition minimum magnitude increase of \\( G_ min = 0.59 0.11\\) mag, corresponding to an approximately \\(42\\%\\) reduction in brightness each return. This trend implies that the comet's active fraction has declined by about an order of magnitude since 1991 and may indicate that Hartley 2 is no longer hyperactive by definition. The fading is consistent with progressive volatile depletion rather than orbital effects. These results offer insight into the evolutionary processes shaping Jupiter-family comets.