Carbamatos são os pesticidas mais frequentemente encontrados em alimentos e bebidas de coloração escura em casos de intoxicação acidental ou intencional. Neste trabalho, extração líquido-líquido com partição em baixa temperatura (LLE-LTP) foi otimizada e validada para determinação dos carbamatos aldicarb, carbofuran e carbaril em bebidas de sucos de uva e leite achocolatado. Este método envolve a extração com acetonitrila, partição líquido-líquido em baixa temperatura e análise por cromatografia líquida de alta eficiência com detecção ultravioleta (HPLC-UV). O método é rápido, eficiente e de baixo custo, emprega pequenos volumes de solvente por amostra e não necessita de limpeza dos extratos. O método de extração foi seletivo e apresentou porcentagens de extração acima de 90%. As premissas relacionadas com os testes estatísticos de linearidade foram verificadas e confirmadas. O método de extração e análise foi validado com resultados satisfatórios e pode ser aplicado em análises de rotina e forenses.Carbamates are the pesticides most commonly found in dark colored foods and beverages in cases of accidental or intentional poisoning. In this work, the liquid-liquid extraction with low temperature partitioning (LLE-LTP) was optimized and validated for determination of the carbamates aldicarb, carbofuran and carbaryl in grape juice and chocolate milk beverages. This method involved extraction with acetonitrile, liquid-liquid partition at low temperature and the analysis by high performance liquid chromatography with ultraviolet detection (HPLC-UV). The method is rapid, efficient and of low-cost, employing small volumes of solvent per sample and requiring no cleanup of the extracts. The extraction methodology was selective and presented recovery percentages above 90%. The premises related to the statistical linearity tests were checked and confirmed. The method of extraction and analysis was validated with satisfactory results, and may be applied in forensic and routine analysis Keywords: carbamates, low temperature partitioning, high performance liquid chromatography, sample preparation, validation IntroductionCarbamate insecticides are widely used in gardening and agriculture due to their broad spectrum of activity and relatively short environmental persistence. However, they are potentially toxic to humans, particularly in the context of intentional self-poisoning. 1,2 Carbamates are found as commercialized products for agricultural practices and some compounds of this group, with their respective commercial names are: carbaryl (Sevin ® ), aldicarb (Temik ® ) and carbofuran (Furadan ® ). From these, aldicarb stands out as the main target on the list of controlled pesticides of the United States Environmental Protection Agency (EPA) due to its elevated toxicity to mammals. 3,4 The maximum residue level (MRL) of aldicarb 5,6 and carbofuran 6 in water is 10 and 7 μg L -1 , respectively. In Goulart et al. 1155 Vol. 23, No. 6, 2012 milk, the MRLs established for aldicarb, 7,8 Exposures may occur accidentally, with ...
O luminol é um teste presuntivo para detecção de manchas de sangue, muito sensÃvel, efetivo e seletivo. O objetivo deste trabalho é avaliar a eficácia do luminol na detecção de sangue após o entintamento das paredes em um local onde ocorreu um homicÃdio. Os peritos se dirigiram para a casa do suspeito e com o uso de uma espátula metálica retiraram parte do revestimento da parede do quarto e após nova aplicação do luminol observaram a mancha branco-azulada, intensa e de duração tÃpica de sangue latente. Os fragmentos retirados da parede foram enviados para o laboratório de DNA que confirmou tratar-se de sangue da vÃtima. A aplicação dessa técnica no caso em questão encontrando manchas de sangue sob a pintura ajudou a perÃcia a traçar a dinâmica do evento, ficando mais clara a posição da vÃtima quando foi alvejada com tiros pelo seu agressor além de ligar aquele local à vÃtima. O luminol não é capaz de detectar sangue que está sob a tinta da parede. A deteção do sangue latente somente ocorre quando a camada de tinta é retirada.
One of the highest incidences of illegal drug products is related to phosphodiesterase-5 inhibitors, used in treatment of erectile dysfunction, including those containing sildenafil citrate and tadalafil. In this context, comprehensive evaluation of the quality of genuine and illegal medicines was performed. A simple and rapid ultra-high performance liquid chromatography (UHPLC-UV) method to quantify sildenafil and tadalafil in the presence of six degradation products was developed and validated. Sildenafil and tadalafil were submitted to forced degradation. The separation was carried out on a Kinetex C18 (50 × 2.1 mm; 1.7 μm) column with mobile phase composed of acetonitrile and aqueous triethylamine solution. The calibration curves were linear in the range of 14–126 μg mL−1 for sildenafil citrate and 4–36 μg mL−1 for tadalafil and the method proved to be selective, precise, accurate and robust. Sildenafil degraded in oxidative media, whereas tadalafil degraded in acidic, alkaline and oxidative environment. The chemical structures and the mechanisms for the formation of the main degradation products were proposed by UHPLC coupled to tandem mass spectrometry. The UHPLC-UV method was applied in the pharmaceutical analysis of genuine and seized medicines. Some of them did not meet quality standards, mainly due to contents below specifications and the large variation on contents between units within a batch.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.