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1.
Drug Dev Ind Pharm ; 46(7): 1092-1099, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32475190

RESUMO

Meloxicam (MLX) is a non-steroidal anti-inflammatory which is practically insoluble in water, requiring high concentrations to reach therapeutic levels and causing frequently gastrointestinal effects. In this way, the aim of this study was to synthesize two eutectic mixtures of MLX with mandelic acid (MND) and saccharin (SAC) by liquid-assisted grinding resulting in a multicomponent material with enhanced solubility. Mixtures were studied in different stoichiometric and eutectic point was found for each eutectic by Binary phase diagram and Tamman's triangle, with 0.33 molar fraction of MLX for SAC and MND. Eutectics were characterized by thermoanalytical techniques (TG-DSC, EGA, DSC, and DSC microscopy), infrared spectroscopy, and X-ray powder diffraction. Thermal behavior was studied and videos of the materials being heated were available. A polymorphic transition was discovered and studied for MLX-MND eutectic. Each new system was evaluated by solubility, dissolution, and hygroscopicity tests. Eutectics showed an increase in solubility of 1.7× (MLX-MND1), 3.1× (MLX-MND2), and 1.3× (MLX-SAC) with slower dissolution profile when compared with MLX. All new solid forms showed high hygroscopicity at 98% relative humidity with 27.9 and 58.9% increase in mass at day four for MLX-SAC and MLX-MND, deliquescence occurs at day 6. The experiments and analysis in this study help to understand the behavior of eutectics and evaluate them as an approach to modify properties in drugs.


Assuntos
Ácidos Mandélicos , Meloxicam/síntese química , Sacarina , Meloxicam/química , Solubilidade , Difração de Raios X
2.
Food Chem ; 237: 1149-1154, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28763963

RESUMO

This work investigates the thermal behavior of α and ß myo-inositol polymorphs. The inositol is a natural compound widely used in the food industry due to its presence in carbohydrate metabolism and its sweet taste. The occurrence of polymorphism could change some physico-chemical properties, such as melting and sublimation temperatures, and solubility. Therefore, the thermal study of polymorphism is important to ensure better conditions for synthesis, storage, and transportation of food that contains the myo-inositol. Simultaneous Termogravimetry-Differential Thermal Analysis, Photovisual Differential Scanning Calorimetry, Polarized Light Thermomicroscopy, and Powder X-ray Diffraction were used in investigation. The data show a new thermal event associated to ß myo-inositol melting at 221.43°C, suggesting that the solid-solid transition at 185.68°C was incomplete. The kinetics data made it possible to determine the transition lifetime of myo-inositol to occur 5% of solid-solid transition at 20°C and 37°C: 126 and 8years, respectively.


Assuntos
Inositol/química , Edulcorantes/química , Varredura Diferencial de Calorimetria , Solubilidade , Difração de Raios X
3.
Food Chem ; 237: 561-565, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28764035

RESUMO

Resveratrol is a natural polyphenol found in various plants, mainly in the bark of the red grapes. It has been widely studied due to its antioxidant, anti-inflammatory, anticancer and anti-aging properties. The thermal behavior of resveratrol was investigated by using simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), evolved gas analysis (TG-DSC-FTIR) and High-resolution mass spectra (HRMS). The results provided information concerning the thermal stability, thermal decomposition, identification of the main gaseous products evolved and intermediate compounds formed during the thermal decomposition.


Assuntos
Estilbenos/análise , Antioxidantes , Varredura Diferencial de Calorimetria , Resveratrol , Termogravimetria
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