Ko C, Dixit V, Shaw W, Gitnick G
Division of Plastic Surgery, UCLA School of Medicine 90024-7019, USA.
Artif Cells Blood Substit Immobil Biotechnol. 1995;23(2):143-51. doi: 10.3109/10731199509117934.
Although a variety of angiogenic growth factors have been isolated, its appropriate in vivo delivery remains problematic due to nonspecific, uncontrolled delivery by conventional methods. We have investigated calcium alginate microbeads as a vehicle for the controlled slow-release of endothelial cell growth factor (ECGF). Three different microbead compositions, dependent on ECGF amount and alginate percentage were studied. Microbeads were incubated in a 1.5% calcium chloride solution and release of ECGF into solution was measured spectrophotometrically at specific timepoints. Our results show release rate and amount released after the first 2 hours are dependent on initial quick delivery of ECGF in the first 2 hours after which a sustained controlled release occurred for 4-5 days. Beyond this point, release at a slower rate was noted for at least approximately 2 weeks. Calcium alginate microbeads demonstrated a controlled and predictable rate of release and that the amount of ECGF delivered can be varied by varying the initial concentration of ECGF in the microbeads. Based on these observations we conclude that calcium alginate microbeads are a convenient and practical vehicle for sustained ECGF delivery.
尽管已经分离出多种血管生成生长因子，但由于传统方法的非特异性、不受控递送，其在体内的适当递送仍然存在问题。我们研究了海藻酸钙微珠作为内皮细胞生长因子（ECGF）可控缓释载体的情况。研究了三种不同的微珠组成，它们取决于ECGF的量和海藻酸盐的百分比。将微珠在1.5%的氯化钙溶液中孵育，并在特定时间点用分光光度法测量ECGF向溶液中的释放量。我们的结果表明，最初2小时后的释放速率和释放量取决于最初2小时内ECGF的快速递送，在此之后，持续控释持续4-5天。超过这一点，至少在大约2周内观察到释放速率较慢。海藻酸钙微珠表现出可控且可预测的释放速率，并且通过改变微珠中ECGF的初始浓度，可以改变递送的ECGF量。基于这些观察结果，我们得出结论，海藻酸钙微珠是一种方便实用的ECGF持续递送载体。
