Maghemite nanoparticles synthesized by one-pot synthesis adsorb diclofenac efficiently.

In this paper a new Fenton catalyst composed of iron oxide doped with a small amount of Cu was developed.

Rare diseases affect a small part of the population, and the most affected are children. Because of the low availability of patients for testing, the pharmaceutical industry cannot develop drugs for the diagnosis of many of these orphan diseases. In this sense, the use of benzothiazole compounds that are highly selective and can act as spectroscopy probes, especially the compound 2-(4′-aminophenyl)benzothiazole (ABT), has been highlighted. This article reports the design of potential contrast agents based on ABT and iron to develop a new material with an efficient mechanism to raise the relaxation rate, facilitating diagnosis. The ABT/δ-FeOOH hybrid material was prepared by grafting (N-(4’-aminophenyl) benzothiazole-2-bromoacetamide) on the surface of the iron oxyhydroxide particles. FTIR spectra confirmed the material formations of the hybrid material ABT/δ-FeOOH. SEM analysis checked the covering of nanoflakes’ surfaces in relation to the morphology of the samples. The theoretical calculations test a better binding mode of compound with iron oxyhydroxide. Theoretical findings show the radical capture mechanism in the stabilization of this new material. In this context, Fe3+ ions are an electron acceptor from the organic phase.

Theδ-FeOOH/PMMA nanocomposites with 0.5 and 2.5 wt.% ofδ-FeOOH were prepared by grafting 3-(trimethoxysilyl)propyl methacrylate on the surface of the iron oxyhydroxide particles. The FTIR spectra of theδ-FeOOH/PMMA nanocomposites showed that the silane monomers were covalently attached to theδ-FeOOH particles. Because of the strong interaction between the PMMA andδ-FeOOH nanoparticles, the thermal stability of theδ-FeOOH/PMMA nanocomposites was improved compared to the pure PMMA. The SEM analysis conferred the size agglomerate of particles regarding the morphology of samples. The theoretical study enabled a better understanding of the interaction of the polymer with the iron oxyhydroxide. The DFT-based calculations reinforce the radical trapping mechanism of stabilization of nanocomposites; that is, Fe3+species might be able to accept electrons coming from the organic phase that decomposes via radical unzipping. The radical scavenge effect delays the weight loss of polymer.

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O procedimento de fabricação do açúcar sofre influência da qualidade do solo, que ao ser fertilizado com agentes minerais ou orgânicos, pode acumular para si elementos metálicos, inclusive os pesados. Assim, verifica-se a necessidade crescente da indústria açucareira brasileira no desenvolvimento de processos que levem a obtenção de produtos com melhor qualidade. Este trabalho consiste de um método para a identificação de cobre em açúcar. O cobre apresenta a propriedade de ser acumulativo no corpo humano causando assim danos à saúde, um desses danos é a doença de Wilson. Desenvolveu-se um método para o monitoramento de cobre em amostras de açúcar utilizando um sistema ternário homogêneo de solventes e espectrofotometria UV-VIS. O sistema ternário foi composto por água, etanol e metilisobutilcetona nas proporções %m/m de 56,04: 26,33: 17,63. Utilizou-se lmax = 370 nm. A curva de calibração apresentou-se: ABS = 0,006[Cu2+] + 0,0012, com R²= 0,9935. As amostras foram analisadas em triplicata e os resultados apresentam um percentual de 0,0023% do metal no açúcar, que é inferior à taxa de consumo considerada normal para o cobre de 0,8 a 10,0 mg/dia, não apresentando desta forma, riscos ao ser humano se consumida diariamente.

Chemical weapons are a major worldwide problem, since they are inexpensive, easy to produce on a large scale and difficult to detect and control. Among the chemical warfare agents, we can highlight the organophosphorus compounds (OP), which contain the phosphorus element and that have a large number of applications. They affect the central nervous system and can lead to death, so there are a lot of works in order to design new effective antidotes for the intoxication caused by them. The standard treatment includes the use of an anticholinergic combined to a central nervous system depressor and an oxime. Oximes are compounds that reactivate Acetylcholinesterase (AChE), a regulatory enzyme responsible for the transmission of nerve impulses, which is one of the molecular targets most vulnerable to neurotoxic agents. Increasingly, enzymatic treatment becomes a promising alternative; therefore, other enzymes have been studied for the OP degradation function, such as phosphotriesterase (PTE) from bacteria, human serum paraoxonase 1 ( Hss PON1) and diisopropyl fluorophosphatase (DFPase) that showed significant performances in OP detoxification. The understanding of mechanisms by which enzymes act is of extreme importance for the projection of antidotes for warfare agents, and computational chemistry comes to aid and reduce the time and costs of the process. Molecular Docking, Molecular Dynamics and QM/MM (quantum-mechanics/molecular-mechanics) are techniques used to investigate the molecular interactions between ligands and proteins.