Centre for Biomedical Engineering, Indian Institute of Technology, New Delhi 110016, India.
Biomed Mater. 2010 Dec;5(6):065014. doi: 10.1088/1748-6041/5/6/065014. Epub 2010 Nov 15.
A biodegradable semi-interpenetrating hydrogel network (semi-IPN) of polyacrylamide and gelatin was prepared using polycaprolactone diacrylate (mol. wt ∼ 640) as a crosslinker. The drug-polymer interaction and IPN formation were investigated by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and thermal gravimetric analysis (TGA). Scanning electron micrographs of lyophilized matrices revealed porous internal structure with varying pore sizes under equilibrium hydrated conditions, depending upon formulation composition. pH-dependent swelling and degradation was enhanced with increasing gelatin content and decreasing crosslinker concentration (Cs). Compression modulus (CM) (at 20% strain) increased significantly from 23 ± 1.4 to 75 ± 2.7 kPa (p < 0.02) with increasing Cs (from 0.5 to 2.0 mol%), while it decreased from 162 ± 6.4 to 23 ± 1.4 kPa (p < 0.05) with decreasing PAm/G ratio. Cell viability studies by MTT assay showed excellent cytocompatibility of matrices with fibroblast L929 cells. Curcumin, a hydrophobic phytochemical, was loaded by a diffusion method and its release profile was investigated in 4% w/v aqueous BSA solution at 75 rpm (at 37 ± 0.2 °C). Fitting of drug release data in the Korsmeyer-Peppas model suggested sustained release behavior up to 10 days with a combination of diffusion and erosion mechanism (0.5 < n < 1.0; M(t)/M(∞) ≤ 0.6). The newly developed porous, biodegradable and elastic semi-IPNs may serve as an ideal matrix for controlled drug release and wound healing applications. The possibilities can be explored for pharmaceutical and tissue engineering applications.
采用聚己内酯二丙烯酸酯（分子量约 640）作为交联剂，制备了聚丙烯酰胺和明胶的可生物降解半互穿水凝胶网络（半 IPN）。通过衰减全反射傅里叶变换红外（ATR-FTIR）和热重分析（TGA）研究了药物-聚合物相互作用和 IPN 形成。在平衡水合条件下，冻干基质的扫描电子显微镜图像显示出具有不同孔径的多孔内部结构，这取决于配方组成。随着明胶含量的增加和交联剂浓度（Cs）的降低，pH 值依赖性溶胀和降解得到增强。在 20%应变下，压缩模量（CM）从 23 ± 1.4 显著增加到 75 ± 2.7 kPa（p < 0.02），随着 Cs（从 0.5 增加到 2.0 mol%）增加，而随着 PAm/G 比的降低，CM 从 162 ± 6.4 降低到 23 ± 1.4 kPa（p < 0.05）。MTT 测定的细胞活力研究表明，基质与成纤维细胞 L929 具有极好的细胞相容性。姜黄素是一种疏水性植物化学物质，通过扩散方法负载，在 75 rpm（37 ± 0.2°C）下在 4%w/v 水性 BSA 溶液中研究其释放曲线。在 Korsmeyer-Peppas 模型中拟合药物释放数据表明，在扩散和侵蚀机制（0.5 < n < 1.0；M(t)/M(∞) ≤ 0.6）的组合下，可实现长达 10 天的持续释放行为。新开发的多孔、可生物降解和弹性半 IPN 可用作控制药物释放和伤口愈合应用的理想基质。可以探索其在药物和组织工程应用中的可能性。
