PDF(Pubmed)
Abstract：
The encapsulation of molecules with different physicochemical properties (theophylline, blue dextran, salicylic acid and insulin) in whey protein (WP) and alginate (ALG) microparticles (MP) for oral administration was studied. MP based on WP/ALG were prepared by a cold gelation technique and coated with WP solution after reticulation. Molecules influenced polymer solution viscosity and elasticity, resulting in differences regarding encapsulation efficiency (from 23 to 100%), MP structure and swelling (>10%) and in terms of pH tested. Molecule release was due to diffusion and/or erosion of MP and was very dependent on the substance encapsulated. All the loaded MP were successfully coated, but variation in coating thickness (from 68 to 146 µm) and function of the molecules encapsulated resulted in differences in molecule release (5 to 80% in 1 h). Gel rheology modification, due to interactions between WP, ALG, calcium and other substances, was responsible for the highlighted differences. Measuring rheologic parameters before extrusion and reticulation appeared to be one of the most important aspects to study in order to successfully develop a vector with optimal biopharmaceutical properties. Our vector seems to be more appropriate for anionic high-molecular-weight substances, leading to high viscosity and elasticity and to MP enabling gastroresistance and controlled release of molecules at intestinal pH.
摘要：
具有不同物理化学性质的分子的封装(茶碱，蓝色右旋糖酐,研究了口服乳清蛋白（WP）和藻酸盐（ALG）微粒（MP）中的水杨酸和胰岛素）。通过冷胶凝技术制备基于WP/ALG的MP，并在网状化后用WP溶液涂覆。分子影响聚合物溶液的粘度和弹性，导致封装效率的差异(从23%到100%)，MP结构和溶胀(>10%)以及就pH而言测试。分子释放是由于MP的扩散和/或侵蚀,并且非常依赖于包封的物质。所有装载的MP均已成功涂覆，但是涂层厚度的变化（从68到146µm）和包封的分子的功能导致分子释放的差异（1小时内5％至80％）。凝胶流变改性，由于WP之间的相互作用，ALG,钙和其他物质，是造成突出差异的原因。为了成功开发具有最佳生物制药特性的载体，在挤出和网状化之前测量流变参数似乎是研究的最重要方面之一。我们的载体似乎更适合阴离子高分子量物质，导致高粘度和弹性，并导致MP，从而在肠道pH值下实现胃抗性和分子的受控释放。
