Department of Mechanics, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.
J Mech Behav Biomed Mater. 2011 Oct;4(7):1318-27. doi: 10.1016/j.jmbbm.2011.04.019. Epub 2011 May 1.
Bone regeneration can be accelerated by localized delivery of appropriate growth factors/biomolecules. Localized delivery can be achieved by a 2-level system: (i) incorporation of biomolecules within biodegradable particulate carriers (nanoparticles), and (ii) inclusion of such particulate carriers (nanoparticles) into suitable porous scaffolds. In this study, freeze-dried porous chitosan-gelatin scaffolds (CH-G: 1:2 ratio by weight) were embedded with various amounts of poly(lactide-co-glycolide) (PLGA) nanoparticles, precisely 16.6%, 33.3% and 66.6% (respect to CH-G weight). Scaffolds loaded with PLGA nanoparticles were subjected to physico-mechanical and biological characterizations including morphological analysis, swelling and dissolution tests, mechanical compression tests and cell viability tests. Results showed that incorporation of PLGA nanoparticles into porous crosslinked CH-G scaffolds: (i) changed the micro-architecture of the scaffolds in terms of mean pore diameter and pore size distribution, (ii) reduced the dissolution degree of the scaffolds, and (iii) increased the compressive modulus. On the other hand, the water uptake behavior of CH-G scaffolds containing PLGA nanoparticles significantly decreased. The incorporation of PLGA nanoparticles did not affect the biocompatibility of CH-G scaffolds.
骨再生可以通过局部递送适当的生长因子/生物分子来加速。局部递送可以通过两级系统实现：（i）将生物分子掺入可生物降解的颗粒载体（纳米颗粒）中，和（ii）将此类颗粒载体（纳米颗粒）纳入合适的多孔支架中。在这项研究中，冻干多孔壳聚糖-明胶支架（CH-G：重量比为 1:2）中嵌入了不同量的聚（乳酸-共-乙醇酸）（PLGA）纳米颗粒，分别为 16.6%、33.3%和 66.6%（相对于 CH-G 的重量）。负载有 PLGA 纳米颗粒的支架进行了物理-机械和生物特性的表征，包括形态分析、溶胀和溶解试验、机械压缩试验和细胞活力试验。结果表明，将 PLGA 纳米颗粒掺入多孔交联 CH-G 支架中：（i）改变了支架的微结构，表现在平均孔径和孔径分布方面，（ii）降低了支架的溶解程度，和（iii）增加了压缩模量。另一方面，含有 PLGA 纳米颗粒的 CH-G 支架的吸水率显著降低。PLGA 纳米颗粒的掺入不影响 CH-G 支架的生物相容性。
