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Wearable solid phase microextraction (SPME) devices consisting in necklaces and pins were developed for the environmental monitoring of ketamine in recreational places using ionic liquid as coating. SPME fibers obtained using both monocationic and dicationic polymeric ionic liquids were characterized in terms of morphology, film thickness, thermal stability and pH resistance. An average thickness of 30 ± 5 μm, an excellent thermal stability until 350 °C and a very good fiber-to-fiber and batch-to-batch repeatability with RSD lower than 4% were some of the features of the developed coatings. A quantitation limit (LOQ) of 0.05 mg/m 3 with a sampling time of 1 min proved the feasibility of the developed method for the quantitation of ketamine in air at low concentration levels. Finally, the capabilities of the fibers for the rapid SPME sampling of ketamine in recreational places were proved obtaining extraction efficiencies at least two-fold higher than those obtained using commercial devices and extraction recoveries ranging from 84.2 ± 3.3% to 93.6 ± 2.6% ( n = 3).

Accepted Manuscript version. The Published Journal Article is available on theJournal of ChromatographyA, Volume 1363, pages 150-154 (DOI: https://doi.org/10.1016/j.chroma.2014.07.069). SupplementaryMaterial available free of charge on the article webpage. © 2014. This Manuscript version is made available under the CC-BY-NC-ND 4.0 license.https://creativecommons.org/licenses/by-nc-nd/4.0/ ABSTRACT Levamisole, an anthelmintic drug, has been increasingly employed as an adulterant of illicit street cocaine over the last decade; recently, the use of tetramisole, the racemic mixture of levamisole and its enantiomer dexamisole, was also occasionally observed. A new enantioselective high-performance liquid chromatography (HPLC) method, performed on cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phases in normal-phase mode, was validated and applied to determine the enantiomeric composition of tetramisole enantiomers in seized cocaine samples. Furthermore, the hyphenation of the validated HPLC method with a circular dichroism (CD) detection system allowed the direct determination of elution order and a selective monitoring of levamisole and dexamisole in the presence of possible interferences. The method was applied to the identification and quantitation of the two enantiomers of tetramisole in seized street cocaine samples.

Molecular mechanisms of adaptive transformations caused by alcohol exposure on opioid dynorphin and nociceptin systems have been investigated in the rat brain. Alcohol was intragastrically administered to rats to resemble human drinking with several hours of exposure: water or alcohol (20% in water) at a dose of 1.5 g/kg three times daily for 1 or 5 days. The development of tolerance and dependence were recorded daily. Brains were dissected 30 minutes (1- and 5-day groups) or 1, 3 or 7 days after the last administration for the three other 5-day groups (groups under withdrawal). Specific alterations in opioid genes expression were ascertained. In the amygdala, an up-regulation of prodynorphin and pronociceptin was observed in the 1-day group; moreover, pronociceptin and the kappa opioid receptor mRNAs in the 5-day group and both peptide precursors in the 1-day withdrawal group were also up-regulated. In the prefrontal cortex, an increase in prodynorhin expression in the 1-day group was detected. These data indicate a relevant role of the dynorphinergic system in the negative hedonic states associated with multiple alcohol exposure. The pattern of alterations observed for the nociceptin system appears to be consistent with its role of functional antagonism towards the actions of ethanol associated with other opioid peptides. Our findings could help to the understanding of how alcohol differentially affects the opioid systems in the brain and also suggest the dynorphin and nociceptin systems as possible targets for the treatment and/or prevention of alcohol dependence.

Accepted Manuscript version. The Published Journal Article is available on theJournal of Pharmaceutical andBiomedical Analysis, Volume 81-82, pages 76-79 (DOI: https://doi.org/10.1016/j.jpba.2013.03.024).SupplementaryMaterial available free of charge on the article webpage. © 2013. This Manuscript version is made available under the CC-BY-NC-ND 4.0 license.https://creativecommons.org/licenses/by-nc-nd/4.0/ ABSTRACT A new enantioselective HPLC method was developed for the resolution and determination of the enantiomers of methorphan, dextromethorphan (DXM) and levomethorphan (LVM), on a Chiralcel® OJ column (250mm×4.6mm I.D.). The resolution of DXM and LVM was obtained using a mobile phase consisting of (n-hexane)-(2-propanol)-diethylamine (70:30:0.1, v/v/v) at a flow rate of 0.5 mL/min. The enantioselective method was found to be selective (α=1.92) and sensitive (LOD=2.8 μg/mL for both DXM and LVM). The method was coupled with electronic circular dichroism (CD), allowing the determination of the elution order based on the sign of CD signals of the single enantiomers at 285nm (positive for DXM, negative for LVM). Under the optimized conditions, the validated method was applied to the identification and quantitation of the enantiomers of methorphan in samples of different sources of illicit drugs of abuse (heroin). DXM was found in eight seized samples of street heroin; two of these samples, for which the DXM content was found to be over 5% (w/w) and exceeding a 10% (w/w) ratio with respect to diacetylmorphine, were the cause of two deaths for overdose due to acute narcotism.

Screening methods based on liquid chromatography (HPLC) and capillary electrophoresis (CE) have been developed for the identification and determination of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and 3,4-methylenedioxyethylamphetamine in illicit tablets. Diethylpropione, (-)-ephedrine, and 3-amino-1-phenylbutane were also included in the study as amphetamino-related compounds. The HPLC-diode-array detection method involved on-line photochemical derivatization to enhance the selectivity of detection allowing amphetamines to be distinguished from related compounds such as diethylpropione (amfepramone). When the CE approach was adopted, two identification parameters (UV spectra and migration index) were used and the enantioresolution of the racemic amphetamines was achieved using hydroxypropyl-beta-cyclodextrin as chiral selector.

The presence and distribution of mesenchymal components in the extracellular matrix during lung development in the chick embryo (from 5 1/2/6 to 18 incubation days) has been examined histochemically. Attention is focused mainly on glycosaminoglycans (GAG). Morphological reconstructions show three main stages: first (5 1/2/6-8 days), formation of 2nd-order branching; second (9-12 days), proliferation of parabronchi and third (from 13th day on), formation of air capillaries. In the first phase, hyaluronic acid (HA) prevails around the mesobronchus, but chondroitin sulfate (CS) dominates the 2nd-order branches. Basement membranes of 2nd-order branches are strongly positive for sulphated GAG. In the second phase, CSA increases in the ground substance of mesenchyme. This increase is irregular, being smaller in older areas (mesobronchus, branches of 2nd order) and larger in the more recent parabronchi, which extend into the lateral and dorsal areas of the rudiment. An increase in both sulfated GAG and glycoprotein (GP) occurs in basement membranes. In the third phase, GAGs are uniformly distributed in the mesenchymal septa and around the interlobular vascular network. This concentration decreases while the GP concentration increases. Basement membranes around every branch of the 1st, 2nd, and 3rd orders possess large quantities of GP. Mesenchymal GAG occurs in every stage of lung development, temporally correlating with the morphogenesis and differentiation of epithelium. Our results provide necessary information, which has not been available so far. Experimental studies specifically designed to clarify the developmental significance of such a heterogeneous distribution may be interpreted in the light of this information.