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In this work voltammetric techniques were explored for quantification of α‐Lipoic acid (ALA) using a pyrolytic graphite electrode modified with cobalt phthalocyanine. Cyclic voltammograms recorded in phosphate buffer solution containing 1×10−3 mol L−1 of ALA presented an oxidation peak located at +0.8 V vs. SCE. The modification of the electrode produced a 100 mV shift of the onset oxidation potential to less positive value and a substantial increase in the ALA oxidation current. Among the voltammetric techniques explored, differential pulse voltammetry showed the best performance for quantifications of the analyte in low concentrations. Limits of detection and quantification of ALA obtained corresponds to 3.4×10−9 mol L−1 and 1.2×10−8 mol L−1, respectively.

The use of nanoparticulate systems with action in breast and ovarian cancer has been highlighted in recent years as an alternative to increasing the therapeutic index of conventional anticancer drugs. Thus, nanoparticles have advantageous characteristics in the treatment of cancer. Several nanocarriers of drugs and nanoparticles are described in the literature. The pharmacokinetics of the drugs can be modified by the use of nanocarriers, which in turn facilitate the specific delivery of the drug to the tumour cell. Therefore, the present work is a review that examines some nanosystems with nanoparticles for action in the treatment of breast cancer and ovarian cancer.

The synthesis of efficient and reusable gold-based catalysts for the selective oxidation of alcohols is a strategy for the development of green processes. Pre-formed nanoparticles syntheses are an easy way to produce controlled-nanosized gold materials; however, the selection of a support is not trivial. Herein, we proposed a CoFe 2 O 4 support enriched with Sr(OH) 2 , which holds remarkable properties and is suitable for the synthesis of a stable gold-based catalyst for the oxidation of benzyl alcohol. We suggested that the interaction between the CoFe 2 O 4 and the Sr(OH) 2 is highly important for the performance of the catalyst. Under the base-free condition of 2.5 h, 100 °C and 2 bar of O 2 , the catalyst reached 58% of conversion with 76% of selectivity to benzaldehyde. With K 2 CO 3 addition, the conversion and selectivity to benzaldehyde increased to 87% and 88%, respectively. Any gold leaching was detected in 5 successive runs, attesting the noticeable stability that the catalyst presents. This work provides great potential for the selective oxidation of alcohols with high activity since the magnetic properties of the catalyst provide an easy route and allows the separation of the medium reaction. In addition, we are here proposing an important interaction between the Sr(OH) 2 and the magnetic nanoparticles.

O amido de mesocarpo de babaçu (Attalea speciosa  Mart. ex Spreng) e a Aloe vera (Aloe vera (L.) Burm. f.) são materiais naturais com vasta aplicação nas áreas de saúde. Neste trabalho de pesquisa foram preparados e caracterizados filmes casting compostos por amido de mesocarpo de babaçu suplementados com Aloe vera nas proporções de 0%, 5%, 8% e 10% observando características físicas de espessura, umidade, solubilidades em água, permeabilidade ao vapor de água e propriedades mecânicas. Além disso, foram avaliadas a citotoxicidade da solução filmogênica em macrófagos murinos da linhagem RAW 264.7 e células de hemácias humanas. Os resultados mostram que os filmes desenvolvidos têm superfície lisa, boa maleabilidade e são autossustentados. O teor de umidade, solubilidade e permeabilidade ao vapor de água aumentaram de acordo com o aumento da concentração de Aloe vera, para as propriedades mecânicas não houve diferença significativa (p>0,05) entre as formulações testadas. A solução filmogênica apresentou efeito citotóxico considerado seguro para os macrófagos e hemácias humanas. Essas características demonstram um bom potencial para cobertura de feridas e reparação tecidual.

Dengue is an infectious viral disease, which can present a wide clinical picture, ranging from oligo or asymptomatic forms, to bleeding and shock, and can progress to death. The disease problem has increased in recent years, especially in urban and suburban areas of tropical and subtropical regions. There are five dengue viruses, called serotypes (DEN-1, DEN-2, DEN-3, DEN-4, and DEN-5), which belong to the Flaviviridae family and are transmitted to humans through infected mosquito bites, with the main vector the Aedes aegypti mosquito (Linnaeus, 1762). Studies performed with Ae. aegypti, aimed at their identification and analysis of their population structure, are fundamental to improve understanding of the epidemiology of dengue, as well for the definition of strategic actions that reduce the transmission of this disease. Therefore, considering the importance of such research to the development of programs to combat dengue, the present review considers the techniques used for the molecular identification, and evaluation of the genetic variability of Ae. aegypti.