Kirchhof Susanne, Brandl Ferdinand P, Hammer Nadine, Goepferich Achim M
University of Regensburg, Department of Pharmaceutical Technology, 93040 Regensburg, Germany.
J Mater Chem B. 2013 Oct 7;1(37):4855-4864. doi: 10.1039/c3tb20831a. Epub 2013 Aug 15.
The Diels-Alder (DA) reaction was investigated as a cross-linking mechanism for poly(ethylene glycol) (PEG) based hydrogels. Two complementary macromonomers were synthesized by functionalizing star-shaped PEG with furyl and maleimide groups. Gel formation occurred in water at 37 °C; the gelation time ranged between 171 ± 25 min and 14 ± 1 min depending on the used hydrogel formulation. The complex shear modulus was dependent on the concentration, branching factor and molecular weight of the macromonomers; values between 2821 ± 1479 Pa and 37097 ± 6698 Pa were observed. Hydrogel swelling and degradation were influenced by the same parameters; the degradation time varied between a few days and several weeks. Gel dissolution was found to occur by retro-DA reaction and subsequent hydrolysis of maleimide groups. Calculations of the network mesh size revealed that the prepared hydrogels would be suitable for the controlled release of therapeutic proteins.
研究了狄尔斯-阿尔德（DA）反应作为聚乙二醇（PEG）基水凝胶的交联机制。通过用呋喃基和马来酰亚胺基团对星形PEG进行官能化，合成了两种互补的大分子单体。凝胶在37℃的水中形成；根据所用水凝胶配方，凝胶化时间在171±25分钟至14±1分钟之间。复数剪切模量取决于大分子单体的浓度、支化因子和分子量；观察到的值在2821±1479帕至37097±6698帕之间。水凝胶的溶胀和降解受相同参数影响；降解时间在几天到几周之间变化。发现凝胶溶解是通过逆DA反应和随后马来酰亚胺基团的水解发生的。网络网孔尺寸的计算表明，所制备的水凝胶适用于治疗性蛋白质的控释。
