Kangarlou Sogol, Haririan Ismaeil, Gholipour Yaghob
Department of Pharmaceutics, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
Int J Pharm. 2008 May 22;356(1-2):153-66. doi: 10.1016/j.ijpharm.2008.01.032. Epub 2008 Jan 24.
This research was conducted to investigate the physico-mechanical characteristics of the EC-based coating membranes plasticized with two informal ingredients of vitamin resources, cholecalciferol and alpha-tocopherol, with respect to the commercial plasticizer DBS. Proceeding the experiment, free thin polymer sheetings of the sample formulations, incorporating incremental weight percents of the individual plasticizers were prepared employing a revised casting method of delayed solvent evaporation whereby similar flat specimens of standard dimensions were subjected to tensile loadings and extensions. The data were analyzed through the known equations of membrane theory in spherical subjects considering the complete symmetry of assumingly spherical pellets and/or granules. The relative tensile parameters of the experimental and commercial plasticizers in the resilient region were also estimated to fairly decide on a moderate explanation of a strong, hard, and tough structure among the specimens. The results implied the great compatibility of the oily soluble vitamins in EC networks projecting higher factors of safety and greater ultimate strength, toughness, and young coefficient of the formulations compared to the specimens plasticized with the commercial DBS within a concentration range of 40-50% (w/w) of the polymer solids. alpha-Tocopherol represented supremacy over colecalciferol to result in relatively a 2-fold (and practically a 4-fold with respect to DBS) greater increase in the modulus of resilience. The vitamin compounds and in essential alpha-tocopherol, in consequence, can properly be applied at concentrations of 40-50% (w/w) as efficient plasticizers to provide a greater protection of the structure against sudden fractures of dynamic and continuously increasing environmental and biological stresses.
本研究旨在探讨用两种维生素资源的非常规成分胆钙化醇和α-生育酚增塑的基于乙基纤维素(EC)的涂膜的物理机械特性,并与商业增塑剂邻苯二甲酸二丁酯(DBS)进行比较。在实验过程中,采用改进的延迟溶剂蒸发流延法制备了含有不同重量百分比增塑剂的样品配方的自由聚合物薄片,将类似标准尺寸的扁平试样进行拉伸加载和拉伸。考虑到假定为球形的粒料和/或颗粒的完全对称性,通过球形容器中膜理论的已知方程对数据进行分析。还估计了弹性区域中实验增塑剂和商业增塑剂的相对拉伸参数,以便对试样中强、硬和韧性结构进行适度解释。结果表明,在聚合物固体浓度为40-50%(w/w)的范围内,油溶性维生素在EC网络中具有良好的相容性,与用商业DBS增塑的试样相比,具有更高的安全系数、更大的极限强度、韧性和杨氏模量。α-生育酚比胆钙化醇表现出优势,导致弹性模量相对增加2倍(相对于DBS实际上增加4倍)。因此,维生素化合物,尤其是α-生育酚,可以在40-50%(w/w)的浓度下作为有效的增塑剂使用,以更好地保护结构免受动态和不断增加的环境及生物应力的突然破坏。