Zhang Y, Chu C C
Fiber and Polymer Science Program, Department of Textiles and Apparel, Cornell University, Ithaca, New York 14853-4401, USA.
J Biomed Mater Res. 2001 Jan;54(1):1-11. doi: 10.1002/1097-4636(200101)54:1<1::aid-jbm1>3.0.co;2-m.
The objective of this paper was to study the release of bovine serum albumin (BSA) from a series of biodegradable hydrogels having a wide range of hydrophilicity to hydrophobicity, swelling, and biodegradation properties. BSA was incorporated into a series of biodegradable hydrogels made from a dextran derivative of allyl isocyanate (dex-AI, as the hydrophilic constituent) and poly(DL-lactic acid) diacrylate macromer (PDLLAM, as the hydrophobic constituent). The release kinetics of BSA from these dex-AI/PDLLAM hydrogels was studied. Laser confocal scanning microscopy was used to investigate the morphological change of the hydrogels, as well as BSA distribution in the hydrogels, as a function of dex-AI to PDLLAM composition ratio and incubation time. We found that the incorporation of PDLLAM into dex-AI reduced the initial burst release of BSA due to its more homogeneous distribution in the hydrogels. As the PDLLAM component increased, the rate of formation of a loose three-dimensional (3D) network structure increased; consequently, the sustained rate and extent of BSA release increased. Both release index and diffusion coefficient (from release kinetics data) increased as the PDLLAM component increased in the hydrogels. The data suggest that the release of BSA was controlled by both diffusion of BSA through swelling of the hydrophilic phase during an early stage, and degradation of the hydrophobic phase during a late stage, and also that the magnitude of diffusion versus degradation controlled release is dependent on composition ratio and immersion time.
本文的目的是研究牛血清白蛋白（BSA）从一系列具有广泛亲水性至疏水性、溶胀性和生物降解性的可生物降解水凝胶中的释放情况。将BSA掺入由异氰酸烯丙酯的葡聚糖衍生物（dex-AI，作为亲水成分）和聚（DL-乳酸）二丙烯酸酯大分子单体（PDLLAM，作为疏水成分）制成的一系列可生物降解水凝胶中。研究了BSA从这些dex-AI/PDLLAM水凝胶中的释放动力学。使用激光共聚焦扫描显微镜研究水凝胶的形态变化以及水凝胶中BSA的分布，作为dex-AI与PDLLAM组成比和孵育时间的函数。我们发现，将PDLLAM掺入dex-AI中可减少BSA的初始突释，这是由于其在水凝胶中的分布更均匀。随着PDLLAM成分的增加，松散三维（3D）网络结构的形成速率增加；因此，BSA释放的持续速率和程度增加。随着水凝胶中PDLLAM成分的增加，释放指数和扩散系数（来自释放动力学数据）均增加。数据表明，BSA的释放早期受BSA通过亲水相溶胀的扩散控制，后期受疏水相降解控制，而且扩散与降解控制释放的程度取决于组成比和浸泡时间。
