Chen Fa-ming, Wu Zhi-fen, Jin Yan, Wu Hong, Du Yan, Wang Guo-fang, Nie Xin
Dept of Periodontology and Oral Medicine, College of Stomatology, The Fourth Military Medical University, Xi'an, China.
Hua Xi Kou Qiang Yi Xue Za Zhi. 2005 Dec;23(6):529-33.
To prepare enamel matrix proteins (EMPs) loaded dextran-based hydrogel microspheres (EMPs-dex-MPs), and to evaluate their EMPs controlled release property and their biological effects on the proliferation and differentiation of human periodontal ligament cells (PDLCs) in vitro.
Using dimethylbenzene as the oil phase, EMPs-dex-MPs were achieved by emulsion-chemical crosslinking technique. The process of the recombination preparation was optimized by orthogonal factorization method. The configuration and size of EMPs-dex-MPs were determined by scanning electron microscope. The EMPs loading content and encapsulation rate of EMPs-dex-MPs, and their biodegradation characteristic were studied by routine analysis methods. Dynamic dialysis method was used to determine the release characteristic of EMPs-dex-MPs in vitro and its influencing factors. The proliferation of cultured PDLCs was measured by MTF method and the differentiation of PDLCs was measured by their alkaline phosphatase (ALP) activities.
The results showed that EMPs-dex-MPs were homogenous and stable with the average diameter 25 microm, and the EMPs loading content was (32.8 +/- 1.2)%, the encapsulation rate was (78.9 +/- 1.0)%. Under 9% physiological saline solution contained a very thimbleful quantity of dextranase EMPs-dex-MPs could be biodegraded completely during about 40 days. The in vitro experiments showed that about 80% of EMPs could be released out in 20 days. Using EMPs-dex-MPs could enhance the proliferation responses and ALP activities of PDLCs more than 12 days.
As a new sustained release system of growth factors, the dex-MPs is stable, workable and biodegradable. EMPs-dex-MPs, whose drug release can be controlled by preparation technique, may be more effective in promoting periodontal tissue regeneration.
制备负载釉基质蛋白（EMPs）的葡聚糖基水凝胶微球（EMPs - dex - MPs），并评估其对EMPs的控释性能以及对人牙周膜细胞（PDLCs）体外增殖和分化的生物学效应。
以二甲苯为油相，采用乳化 - 化学交联技术制备EMPs - dex - MPs。通过正交试验法优化复合制剂的制备工艺。用扫描电子显微镜观察EMPs - dex - MPs的形态和大小。采用常规分析方法研究EMPs - dex - MPs中EMPs的负载量、包封率及其生物降解特性。用动态透析法测定EMPs - dex - MPs的体外释放特性及其影响因素。采用MTT法检测培养的PDLCs的增殖情况，通过碱性磷酸酶（ALP）活性检测PDLCs的分化情况。
结果显示，EMPs - dex - MPs均匀稳定，平均直径为25微米，EMPs负载量为（32.8±1.2）%，包封率为（78.9±1.0）%。在含微量葡聚糖酶的9%生理盐溶液中，EMPs - dex - MPs约40天可完全生物降解。体外实验表明，约80%的EMPs在20天内可释放出来。使用EMPs - dex - MPs可使PDLCs的增殖反应和ALP活性增强超过12天。
作为一种新型的生长因子缓释系统，葡聚糖微球稳定、可行且可生物降解。EMPs - dex - MPs的药物释放可通过制备技术控制，在促进牙周组织再生方面可能更有效。
