Sadeghi Mohammad, Heidari Behrouz
Department of Chemistry, Science Faculty, Islamic Azad University, Arak Branch, 38156 Arak, Iran.
Department of Chemical Engineering, Engineer Faculty, Islamic Azad University, Arak Branch, 38156 Arak, Iran.
Materials (Basel). 2011 Mar 2;4(3):543-552. doi: 10.3390/ma4030543.
In this paper, a novel gelatin-based hydrogel was synthesized through crosslinking graft copolymerization of methacrylic acid (MAA) onto gelatin, using ammonium persulfate (APS) as a free radical initiator in the presence of methylenebisacrylamide (MBA) as a crosslinker. A proposed mechanism for hydrogel formation was suggested and the structure of the product was established using FTIR spectroscopy and gravimetric analysis of the products. Moreover, morphology of the samples was examined by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA/DTG). The effect of reaction variables such as concentration of APS and MBA were systematically optimized to achieve a hydrogel with swelling capacity as high as possible. The gelatin-g-PMAA hydrogel exhibited a pH-responsiveness character so that a swelling-deswelling pulsatile behavior was recorded at pHs 2 and 8. This on-off switching behavior makes the hydrogel as a good candidate for controlled delivery of bioactive agents.
在本文中，以过硫酸铵（APS）作为自由基引发剂，在亚甲基双丙烯酰胺（MBA）作为交联剂存在的条件下，通过甲基丙烯酸（MAA）与明胶的交联接枝共聚反应合成了一种新型的明胶基水凝胶。提出了水凝胶形成的推测机理，并利用傅里叶变换红外光谱（FTIR）和产物的重量分析确定了产物的结构。此外，通过扫描电子显微镜（SEM）和热重分析（TGA/DTG）对样品的形态进行了研究。系统地优化了诸如APS和MBA浓度等反应变量的影响，以获得具有尽可能高溶胀能力的水凝胶。明胶-g-PMAA水凝胶表现出pH响应特性，因此在pH值为2和8时记录到了溶胀-消溶胀的脉动行为。这种开关切换行为使该水凝胶成为生物活性剂控释的良好候选材料。
