Zeeb Benjamin, Saberi Amir Hossein, Weiss Jochen, McClements David Julian
Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany.
Soft Matter. 2015 Mar 21;11(11):2228-36. doi: 10.1039/c4sm02791d.
Delivery systems based on filled hydrogel particles (microgels) can be fabricated from natural food-grade lipids and biopolymers. The potential for controlling release characteristics by modulating the electrostatic interactions between emulsifier-coated lipid droplets and the biopolymer matrix within hydrogel particles was investigated. A multistage procedure was used to fabricate calcium alginate beads filled with lipid droplets stabilized by non-ionic, cationic, anionic, or zwitterionic emulsifiers. Oil-in-water emulsions stabilized by Tween 60, DTAB, SDS, or whey protein were prepared by microfluidization, mixed with various alginate solutions, and then microgels were formed by simple extrusion into calcium solutions. The microgels were placed into a series of buffer solutions with different pH values (2 to 11). Lipid droplets remained encapsulated under acidic and neutral conditions, but were released under highly basic conditions (pH 11) due to hydrogel swelling when the alginate concentration was sufficiently high. Lipid droplet release increased with decreasing alginate concentration, which could be attributed to an increase in the pore size of the hydrogel matrix. These results have important implications for the design of delivery systems to entrap and control the release of lipophilic bioactive components within filled hydrogel particles.
基于填充水凝胶颗粒（微凝胶）的递送系统可以由天然食品级脂质和生物聚合物制成。研究了通过调节乳化剂包被的脂质液滴与水凝胶颗粒内生物聚合物基质之间的静电相互作用来控制释放特性的潜力。采用多阶段程序制备了填充有由非离子、阳离子、阴离子或两性离子乳化剂稳定的脂质液滴的海藻酸钙珠。通过微流化制备由吐温60、十二烷基三甲基溴化铵、十二烷基硫酸钠或乳清蛋白稳定的水包油乳液，与各种海藻酸盐溶液混合，然后通过简单挤出到钙溶液中形成微凝胶。将微凝胶置于一系列不同pH值（2至11）的缓冲溶液中。当海藻酸盐浓度足够高时，脂质液滴在酸性和中性条件下保持包裹状态，但在高碱性条件（pH 11）下由于水凝胶膨胀而释放。脂质液滴的释放随着海藻酸盐浓度的降低而增加，这可归因于水凝胶基质孔径的增加。这些结果对于设计用于捕获和控制填充水凝胶颗粒内亲脂性生物活性成分释放的递送系统具有重要意义。
