Chemical Engineering and Bioengineering Departments, Hacettepe University, 06800 Beytepe, Ankara, Turkey.
J Mater Sci Mater Med. 2011 Nov;22(11):2467-75. doi: 10.1007/s10856-011-4422-4. Epub 2011 Sep 8.
In this study, poly(acrylamide), poly(AAm), and poly(acrylamide-co-acrylic acid), poly(AAm-co-AA) superporous hydrogels (SPHs) were synthesized by radical polymerization in the presence of gas blowing agent, sodium bicarbonate. In addition, ionically crosslinked chitosan (CH) superporous hydrogels were synthesized to form interpenetrating superporous hydrogels, i.e. poly(AAm)-CH and poly(AAm-co-AA)-CH SPH-IPNs. The hydrogels have a structure of interconnected pores with pore sizes of approximately 100-150 μm. Although the extent of swelling increased when AA were incorporated to the poly(AAm) structure, the time to reach the equilibrium swelling (30 s) was not affected so much. In the presence of chitosan network mechanical properties significantly improved when compared with SPHs, however, equilibrium swelling time (30 min) was prolonged significantly as due to the lower porosities and pore sizes of SPH-IPNs than that of SPHs. Model protein bovine serum albumin (BSA) was loaded into SPHs and SPH-IPNs by solvent sorption in very short time (<1 h) and very high capacities (~30-300 mg BSA/g dry gel) when compared to conventional hydrogels. BSA release profiles from SPHs and SPH-IPNs were characterized by an initial burst of protein during the first 20 min followed by a completed release within 1 h. However, total releasable amount of BSA from SPH-IPNs was lower than that of SPHs as due to the electrostatic interactions between chitosan and BSA.
在这项研究中，通过自由基聚合在气体发泡剂碳酸氢钠的存在下合成了聚丙烯酰胺（poly(acrylamide)，poly(AAm)）和聚丙烯酰胺-丙烯酸共聚物（poly(acrylamide-co-acrylic acid)，poly(AAm-co-AA)）超多孔水凝胶（SPHs）。此外，还合成了离子交联壳聚糖（chitosan，CH）超多孔水凝胶，形成互穿超多孔水凝胶，即聚（AAm）-CH 和聚（AAm-co-AA）-CH SPH-IPNs。水凝胶具有相互连接的孔结构，孔径约为 100-150μm。尽管当 AA 被掺入到聚（AAm）结构中时，溶胀程度增加，但达到平衡溶胀的时间（约 30 秒）并没有受到太大影响。当与 SPH 相比时，壳聚糖网络的存在使机械性能显著提高，但由于 SPH-IPNs 的比表面积和孔径比 SPH 低，因此平衡溶胀时间（约 30 分钟）显著延长。将模型蛋白牛血清白蛋白（bovine serum albumin，BSA）通过溶剂吸收短时间（<1 小时）和高容量（~30-300mgBSA/g 干凝胶）负载到 SPH 和 SPH-IPNs 中，与传统水凝胶相比。通过初始蛋白质突释，BSA 从 SPH 和 SPH-IPNs 中的释放曲线在最初的 20 分钟内，然后在 1 小时内完成释放。然而，由于壳聚糖和 BSA 之间的静电相互作用，SPH-IPNs 中可释放的 BSA 总量低于 SPHs。
