Bioprospecting a Film-Forming System Loaded with Eugenia uniflora L. and Tropaeolum majus L. Leaf Extracts for Topical Application in Treating Skin Lesions.

Natural products can be used as complements or as alternatives to synthetic drugs. Eugenia uniflora and Tropaeolum majus are natives of Brazil and have antimicrobial, anti-inflammatory, and antioxidant activities. This study aimed to develop a film-forming system (FFS) loaded with plant extracts with the potential for treating microbial infections. E. uniflora and T. majus leaf extracts were prepared and characterized, and the individual and combined antioxidant and antimicrobial activities were evaluated. The FFS was developed with different concentrations of polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) and analyzed for physicochemical characteristics. The combination of extracts showed a superior antioxidant effect compared to the individual extracts, justifying the use of the blend. FFS prepared with 4.5% PVA, 4.5% PVP, 7.81% E. uniflora extract, and 3.90% T. majus extract was adhesive, lacked scale formation, presented good malleability, and had a suitable pH for topical application. In addition, the viscosity at rest was satisfactory for maintaining stability; water solubility was adequate; skin permeation was low; and the antimicrobial effect was superior to that of the individual extracts. Therefore, the developed FFS is promising for the differentiated treatment of skin lesions through topical application.

Simultaneous accelerated solvent extraction and hydrolysis of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid glucuronide in meconium samples for gas chromatography-mass spectrometry analysis.

Cannabis misuse during pregnancy is associated with severe impacts on the mother and baby health, such as newborn low birth weight, growth restriction, pre-term birth, neurobehavioral and developmental deficits. In most of the cases, drug abuse is omitted or denied by the mothers. Thus, toxicological analyzes using maternal-fetal matrices takes place as a suitable tool to assess drug use. Herein, meconium was the chosen matrix to evaluate cannabis exposure through identification and quantification of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic (THCCOOH). Accelerated solvent extraction (ASE) was applied for sample preparation technique to simultaneously extract and hydrolyze conjugated THCCOOH from meconium, followed by a solid-phase extraction (SPE) procedure. The method was developed and validated for gas chromatography-mass spectrometry (GC-MS), reaching hydrolysis efficiency of 98%. Limits of detection (LOD) and quantification (LOQ) were, respectively, 5 and 10 ng/g. The range of linearity was LOQ to 500 ng/g. Inter and intra-batch coefficients of variation were <8.4% for all concentration levels. Accuracy was in 101.7-108.9% range. Recovery was on average 60.3%. Carryover effect was not observed. The procedure was applied in six meconium samples from babies whose mothers were drug users and showed satisfactory performance to confirm fetal cannabis exposure.

Determination of ketamine, norketamine and dehydronorketamine in urine by hollow-fiber liquid-phase microextraction using an essential oil as supported liquid membrane.

Here, we present a method for the determination of ketamine (KT) and its main metabolites, norketamine (NK) and dehydronorketamine (DHNK) in urine samples by using hollow-fiber liquid-phase microextraction (HF-LPME) in the three-phase mode. The fiber pores were filled with eucalyptus essential oil and a solution of 1.0mol/L of HCl was introduced into the lumen of the fiber (acceptor phase). The fiber was submersed in the alkalinized urine containing 10% NaCl, and the system was submitted to lateral shaking (2400rpm) during 30min. Acceptor phase was withdrawn from the fiber, dried and the residue was then derivatized with trifluoroacetic anhydride (TFAA) for further determination by gas chromatography-mass spectrometry (GC-MS). The calibration curves were linear over the specified range and limits of detection (LoDs) obtained for KT, NK and DHNK were below the cut-off value (1.0ng/mL) recommended by the United Nations Office on Drugs and Crime (UNODC). A totally "green chemistry" approach of the sample extraction was obtained by using essential oil as a supported liquid membrane in HF-LPME. The developed method was successfully validated and applied to urine samples collected from two clinical cases in which KT was suspected to be involved.

Redistribuição postmortem de barbitúricos em tecidos biológicos humanos / Postmortem redistribution of barbiturates in human biological tissues

Os barbitúricos são fármacos com atividade depressora do sistema nervoso central e estão relacionados com elevados números de casos de intoxicações e uso não-médico em vários países. No Brasil, a droga antiepiléptica mais encontrada em casos de intoxicação é o fenobarbital, pois os pacientes relatam que "essa é uma substância com ação forte no cérebro". De fato, os barbitúricos estão altamente relacionados com tentativa de suicídio e homicídio. Nesses casos existe a necessidade da quantificação dessas substâncias para correlacionar com a causa mortis. No entanto, as análises toxicológicas postmortem são de difícil execução e interpretação, pois a concentração de agentes tóxicos encontrados é bastante complexa e afetada não só pela condição de deterioração do corpo, mas também por um processo conhecido como redistribuição postmortem. Em geral, concentrações mais elevadas são encontradas no sangue situado nos sítios centrais (como o sangue coletado da cavidade cardíaca) em comparação aos níveis verificados nos vasos periféricos (como a veia femoral). Em outros casos, o tempo entre a morte e o exame postmortem é suficiente para que algumas substâncias que normalmente estariam presentes no sangue não estejam mais disponíveis neste fluido biológico. Há ainda um agravante, pois não existem valores de referências para a maioria das amostras biológicas não-convencionais, dificultando assim a interpretação dos resultados. Os exames toxicológicos devem ser realizados em amostras biológicas e tem como objetivo a avaliação da intoxicação como circunstância qualificadora do delito, como causa de periculosidade ou imputabilidade. O objetivo deste trabalho foi o desenvolvimento e aplicação de métodos de identificação de barbitúricos (butalbital, secobarbital, pentobarbital e fenobarbital) em amostras postmortem (sangue cardíaco, sangue femoral e fígado). Os analitos foram extraídos das amostras utilizando a micro extração em fase líquida (LPME), identificados...

Barbiturates are a class of drugs that act as central nervous system depressant and are associated with high numbers of poisoning cases and non-medical use in several countries. In Brazil, phenobarbital is the most related antiepileptic drug involved in intoxication cases. Patients report that "this drug is a substance with strong action in the brain." In fact, barbiturates are highly related to attempted suicide and homicide cases, in which quantification of these substances to correlate with the possible cause of death is necessary. However, postmortem toxicological analyses are difficult to perform and interpret, because the concentration of toxic agents found is quite complex and affected not only by deterioration condition of the body but also by a process known as postmortem redistribution. In general, higher concentrations are found in the blood located in central sites (e.g. heart cavity) compared with the levels found in peripheral vessels (such as the femoral vein). In other cases, the time between death and postmortem examination is enough for some substances that would normally be present in the blood are no longer available in this biological fluid. Besides, there are few reference values for most non-conventional biological samples, making it difficult to interpret the results. The objective of this work was the development and application of methods for identification of barbiturates (butalbital, secobarbital, pentobarbital and phenobarbital) in postmortem samples (heart blood, femoral blood and liver). The analytes were extracted by using liquid-phase micro extraction (LPME) and quantified by gas chromatography-mass spectrometry (GC-MS). After the development and validation, analytical methods were applied in real cases of eleven corpses autopsied by Death Verification Service of São Paulo City (USP-SVO), with suspected of barbiturates involvement. Nine cases were positive for phenobarbital. The mean ratio of blood femoral / cardiac blood was...