Abstract:
The incorporation of active compounds into polymeric matrices using traditional methods has several drawbacks mainly due to the high volatility and thermal sensitivity of these substances. A solution to this problem could be the incorporation of bioactive compounds forming inclusion complexes as a strategy to improve the chemical stability, bioactivity and achieve controlled release. In this work, β-cyclodextrin/carvacrol inclusion complex was prepared by spray drying to be incorporated into poly(lactic acid) (PLA) and Mater-Bi® films by supercritical CO2 impregnation. The impregnation process was carried out at pressures of 10, 15 and 20 MPa and at 40 °C. Both polymers showed the highest amount of incorporated inclusion complex at 15 MPa, where the percentage of impregnation varied from 0.6 % to 7.1 % in Mater-Bi® and PLA, respectively. Release tests for PLA films impregnated with inclusion complex showed a slow release of the active compound, which did not reach equilibrium after 350 h under the experimental conditions. This prolonged release was not observed in Mater-Bi® due to the lower incorporation of the inclusion complex. The release rate was described herein by a comprehensive phenomenological model considering the decomplexation kinetics combined with the equilibrium and mass transfer expressions.
摘要:
使用传统方法将活性化合物掺入聚合物基质具有几个缺点,主要是由于这些物质的高挥发性和热敏感性。解决此问题的方法可能是掺入形成包合复合物的生物活性化合物,作为提高化学稳定性的策略。生物活性和实现控制释放。在这项工作中,通过喷雾干燥制备β-环糊精/香芹酚包合物,并通过超临界CO2浸渍将其掺入聚乳酸(PLA)和Mater-Bi®薄膜中。浸渍过程在10、15和20MPa的压力和40°C下进行。两种聚合物在15MPa时都显示出最高的掺入量。在Mater-Bi®和PLA中,浸渍百分比从0.6%变化到7.1%,分别。用包合络合物浸渍的PLA膜的释放试验显示活性化合物的缓慢释放,在实验条件下350h后未达到平衡。在Mater-Bi®中未观察到这种延长的释放,因为包合络合物的掺入较低。本文通过综合现象学模型描述了释放速率,该模型考虑了解络合动力学以及平衡和传质表达式。