Lucia Burrai

Enantiomeric Separation of 13 New Amphetamine-Like Designer Drugs by Capillary Electrophoresis, Using Modified--Cyclodextrins

An easy-to-prepare chiral CE method for the enantiomeric separation of 13 new amphetamine-like designer drugs, using CDs as chiral selectors, was developed. Sulfated-β-CD was found to be the best chiral selector among the three used (sulfated-β-CD, caroboxymethyl-β-CD, dimethyl-β-CD). The separation of the analytes was achieved in a fused-silica gel capillary at 20 °C using an applied voltage of +25 kV. The optimized background electrolyte consisted of 63.5 mM H3 PO4 and 46.9 mM NaOH in water. Several electrophoretic parameters such as CD type, CD concentration (1 - 40 mg/mL), buffer pH (2.6, 3.6, 5.0, 6.0), length of the capillary (70 - 40 cm total length), amount of the organic solvent (methanol and acetonitrile) were investigated and optimized.

Cross-reactivities of 41 new amphetamine designer drugs to EMIT® immunoassays

Amphetamine designer drugs are central nervous system stimulants, and are widely diffused in illegal markets. Monitoring of drugs of abuse in biological fluids is successfully used for clinical and forensic applications. In particular, the urine matrix allows the verification of drug intake in the short and medium term. In a forensic toxicology laboratory, typical analysis for these drugs involves an immunoassay screening method. Here we describe the cross-reactivity profiles of 41 new amphetamine designer drugs to the urine drug tests EMIT® II Plus (Amphetamines assay and Ecstasy assay).

ELISA Detection of 30 New Amphetamine Designer Drugs in Whole Blood, Urine and Oral Fluid using Neogen® "Amphetamine" and "Methamphetamine/MDMA" Kits.

Amphetamine designer drugs are central nervous system stimulants that are widely disseminated in the illegal market. Generally, in forensic laboratories, immunoassay methods are the first line of screening for these types of drugs in a biological specimen (typically blood, urine or oral fluid). In this article, we describe the cross-reactivity profiles of 30 new amphetamine designer drugs, using the Neogen(®) [Amphetamine Specific and Methamphetamine/3,4-Methylenedioxymethamphetamine (MDMA) assays] drug tests. To assess the potential matrix influence on the response, each assay was tested on whole blood, urine and oral fluid. Concentrations of 10,000 ng/mL were not sufficient to produce a positive response for the majority of the analyzed amphetamines. This clearly demonstrates that, although these kits are extremely effective for the target drugs for which they are intended (amphetamine, methamphetamine and MDMA), they cannot be used to reliably identify the tested designer drugs in real cases, as these concentrations greatly exceed those expected to be found in forensic samples.

Validated LC–MS-MS Method for Multiresidual Analysis of 13 Illicit Phenethylamines in Amniotic Fluid

A multi-residue analytical method was developed for the determination in amniotic fluid (AF) of 13 illicit phenethylamines, including 12 compounds never investigated in this matrix before. Samples were subject to solid-phase extraction using; hydrophilic-lipophilic balance cartridges which gave good recoveries and low matrix effects on analysis of the extracts. The quantification was performed by liquid chromatography electrospray tandem mass spectrometry. The water-acetonitrile mobile phase containing 0.1% formic acid, used with a C18 reversed phase column, provided adequate separation, resolution and signal-to-noise ratio for the analytes and the internal standard. The final optimized method was validated according to international guidelines. A monitoring campaign to assess fetal exposure to these 13 substances of abuse has been performed on AF test samples obtained from pregnant women. All mothers (n = 194) reported no use of drugs of abuse during pregnancy, and this was confirmed by the analytical data.

Identification and quantitation of 4-bromo-2,5-dimethoxyamphetamine in seized blotters

Blotters are usually impregnated with hallucinogens such as lysergic acid diethylamide (LSD); only rarely other psychoactive substances are detected. In this work we identified 4-bromo-2,5-dimethoxyamphetamine (DOB) and 2,5-dimethoxyamphetamine (DMA) in illicit blotters seized in Italy. This report describes a rapid method for the simultaneous identification and quantitation of DOB and its precursor (DMA) by liquid chromatography tandem mass spectrometry (LC-MS-MS), using 2,3-dimethoxyphenethylamine-d3 as internal standard. Regression equations were linear over the tested concentration range with good correlation coefficients. The achieved levels of sensitivity may be suitable to confirm the possible presence of DOB and DMA also in low concentration or in traces in seized material for forensic analysis. The developed method showed good reproducibility and sensitivity, and could be used for similar routine analysis. To our knowledge, this is the first report describing the detection of DOB and DMA from blotters.

LC-MS/MS analysis of acetaminophen and caffeine in amniotic fluid

The intake of several substances by pregnant women could be hazardous to the fetus and mothers health: many substances can cross the placenta and reach the fetal compartment, causing adverse outcomes. Consequently, to accurately measure the presence of xenobiotics in fetal matrices, sensitive and specific bioanalytical methods are necessary: this would allow the assessment of fetal exposure to substances which, although licit, can be dangerous for the fetal and childs growth. The aim of this study was to develop and validate a liquid chromatography tandem mass spectrometry method for the simultaneous determination and quantitation of caffeine and acetaminophen in amniotic fluid. Amniotic fluid is a quite complex biological matrix and, as such, it requires a purification step prior to analysis. The extraction method has been optimized by comparing three different commercially available SPE cartridges (Supel™ Select HLB, Phenomenex Strata C18-E, and Agilent ABS Elut-NEXUS), and a liquid/liquid extraction with acetonitrile. A reverse-phase HPLC with a C18 column and gradient elution program was used. MS detection was carried out in MRM mode. Quantitation was performed using the internal standard method. Validation parameters were very satisfactory. The high selectivity and sensitivity of the method (LOQ < 9.5 ng mL−1, and LOD < 3.3 ng mL−1) allowed us to determine target analytes even in small amounts. Precision, matrix effect, and stability were also evaluated. The whole validated method has finally been applied to the analysis of 194 real samples of human amniotic fluid obtained from pregnant women (15–21 weeks of gestation) in order to monitor the effective intake of target analytes: 96% of the examined women consumed caffeine during pregnancy while a lower percentage (20%) showed acetaminophen intake. The whole procedure is simple and easy to perform with minimal sample preparation and short analysis time.

Blood serum retinol levels in Asinara white donkeys reflect albinism-induced metabolic adaptation to photoperiod at Mediterranean latitudes

Abstract Previous works on albinism form of Asinara white donkeys (Equus asinus) identified the mutation leading to the peculiar phenotype spread to all specimens of the breed. Inbreeding naturally occurred under geographic isolation, on Asinara Island, in the Mediterranean Sea. Albino individuals can be more susceptible to develop health problems when exposed to natural sun radiation. Alternative metabolic pathways involved in photoprotection were explored in this trial. Nutrition‐related metabolites are believed to contribute to the conservation of Asinara donkeys, in which melanin, guaranteeing photoprotection, is lacking. Biochemical profiles with particular focus on blood serum β‐carotene and retinol levels were monitored. Identical natural grazing conditions for both Asinara (albino) and Sardo (pigmented) donkey breeds were assured on same natural pastures throughout the experimental period. A comparative metabolic screening, with emphasis on circulating retinol and nutrient‐related metabolites between the two breeds, was carried out over one year. Potential intra‐ and interspecimen fluctuations of metabolites involved in photoprotection were monitored, both during negative and positive photoperiods. Differences (p = .064) between blood serum concentrations of retinol from Asinara versus Sardo breed donkeys (0.630 vs. 0.490 μg/ml, respectively) were found. Retinol levels of blood serum turned out to be similar in the two groups (0.523 vs. 0.493 μg/ml, respectively, p = .051) during the negative photoperiod, but markedly differed during the positive one (0.738 vs. 0.486, respectively, p = .016). Blood serum β‐carotene levels displayed to be constantly around the limit of sensitivity in all animals of both breeds. Variations in blood serum concentrations of retinol in Asinara white donkeys can reflect the need to cope with seasonal exposure to daylight at Mediterranean latitudes, as an alternative to the lack of melanin. These results may suggest that a pulsed mobilization of retinol from body stores occurs to increase circulating levels during positive photoperiod.

Simultaneous Determination of 11 Illicit Phenethylamines in Hair by LC-MS-MS: In Vivo Application.

Existing phenethylamines are a class of synthetic compounds that differ from each other only in small changes to a largely conserved chemical structure. The recreational and illicit use of phenethylamines is a widespread problem. A simple procedure for the simultaneous quantitative determination in hair of 11 phenethylamines that are officially recognized as illicit by Italian legislation (p-methoxyamphetamine; p-methoxymethamphetamine; 3,4,5-trimethoxyamphetamine; 2,5-dimethoxyamphetamine; 2,5-dimethoxy-4-methylamphetamine; 2,5-dimethoxy-4-ethylamphetamine; 2,5-dimethoxy-4-bromoamphetamine; 2,5-dimethoxy-4-bromophenethylamine; 2,5-dimethoxy-4-iodophenethylamine; 2,5-dimethoxy-4-ethylthiophenethylamine and 2,5-dimethoxy-4-n-propylthiophenethylamine) has been developed and validated. Extraction from the matrix was performed after incubation in methanolic HCl and filtered reconstituted extracts were injected into a liquid chromatography/tandem mass spectrometry system (LC-MS-MS) without any further purification steps. This validated LC-MS-MS method has been used to determine the in vivo accumulation/retention of the above target analytes in hair after repeat oral administration to rats. This experiment further permitted investigation of the effect of pigmentation on the uptake of these phenethylamines by hair and the effect of hair pigmentation. The developed method could potentially be used for forensic and toxicological purposes, in the detection and quantitation of these illicit substances in human hair in workplace drug testing; drug-facilitated crime investigation; driver re-licensing; determining drug abuse history and postmortem toxicology.

Galactosylated Pro–Drug of Ursodeoxycholic Acid: Design, Synthesis, Characterization, and Pharmacological Effects in a Rat Model of Estrogen-Induced Cholestasis

Ursodeoxycholic acid (UDCA) is considered the first-choice therapy for cholestatic disorders. To enhance solubility and exploit specific transporters in liver, we synthesized a new galactosyl pro-drug of UDCA (UDCAgal). Ethinylestradiol (EE)-induced cholestasis was used to study and compare the effects of UDCAgal with UDCA on bile flow, hepatic canalicular efflux transporter expression, and inflammation. UDCAgal resulted quite stable both at pH 7.4 and 1.2 and regenerated the parent drug after incubation in human plasma. Its solubility, higher than UDCA, was pH- and temperature-independent. UDCAgal displayed a higher cell permeation compared to UDCA in liver HepG2 cells. Moreover, in cholestatic rats, UDCAgal showed a higher potency compared to UDCA in reducing serum biomarkers (AST, ALT, and ALP) and cytokines (TNF-α and IL-1β). The higher effect of UDCAgal on the increase in bile salt export pump and multidrug resistance-associated protein 2 transcription indicated an improved spillover of bile acids from the liver. UDCAgal showed a reduction in CCL2, as well as TNF-α, IL-1β, and cyclooxygeanse-2 mRNAs, indicating a reduction in hepatic neutrophil accumulation and inflammation. Moreover, UDCAgal, similarly to UDCA, heightens bile flow and modulates biliary acids secretion. These results indicate that UDCAgal has a potential in the treatment of cholestatic disease.

Aceclofenac-galactose conjugate: design, synthesis, characterization and pharmacological and toxicological evaluations.

Aceclofenac is a popular analgesic, antipyretic, and nonsteroidal anti-inflammatory drug (NSAID) used for prolonged treatment (at least three months) in musculoskeletal disorders. It is characterized by several limitations such as poor water solubility and low oral bioavailability. The main side-effect of aceclofenac, as well as all NSAIDs, is the gastrotoxicity; among other adverse effects, there is the risk of bleeding since aceclofenac reversibly inhibits platelet aggregation. With the aim to reduce these drawbacks, we have designed, synthesized, and characterized, both in vitro and in vivo, an orally administrable pro-drug of aceclofenac (ACEgal). ACEgal was obtained by conjugating carboxyl group with the 6-OH group of d-galactose; its structure was confirmed by X-ray powder diffractometry. The pro-drug was shown to be stable at 37 °C in simulated gastric fluid (SGF-without pepsin, pH = 1.2) and moderately stable in phosphate buffered saline (PBS, pH = 7.4). However, it hydrolyzed in human serum with a half-life ( t1/2) of 36 min, producing aceclofenac. Furthermore, if compared to its parent drug, ACEgal was four-times more soluble in SGF. To predict human intestinal absorption, cell permeability in a Caco-2 model of aceclofenac and ACEgal was determined. Anti-inflammatory, analgesic, and ulcerogenic activities have been investigated in vivo. In addition, oxidative stress parameters (thiobarbituric acid reactive substances, TBARS, and glutathione, GSH) and platelet antiaggregatory activity both of parent drug and pro-drug were evaluated. Results clearly showed that the conjugation of aceclofenac to a galactose molecule improves physicochemical, toxicological (at gastric and blood level), and pharmacological profile of aceclofenac itself without changing intestinal permeability and antiplatelet activity (in spite the new sugar moiety).