Kim Arum, Lee Heelim, Jones Clinton F, Mujumdar Siddharthya K, Gu Yuandong, Siegel Ronald A
Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455, USA.
Gels. 2017 Dec 29;4(1):4. doi: 10.3390/gels4010004.
We report here studies of swelling, mechanics, and thermal stability of hydrogels consisting of 20 mol % methacrylamidophenylboronic acid (MPBA) and 80 mol % acrylamide (AAm), lightly crosslinked with methylenebisacrylamide (Bis). Swelling was measured in solutions of fixed ionic strength, but with varying pH values and fructose concentrations. Mechanics was studied by compression and hold. In the absence of sugar or in the presence of fructose, the modulus was mostly maintained during the hold period, while a significant stress relaxation was seen in the presence of glucose, consistent with reversible, dynamic crosslinks provided by glucose, but not fructose. Thermal stability was determined by incubating hydrogels at pH 7.4 at room temperature, and 37, 50, and 65 °C, and monitoring swelling. In PBS (phosphate buffered saline) solutions containing 9 mM fructose, swelling remained essentially complete for 50 days at room temperature, but decreased substantially with time at the higher temperatures, with accelerated reduction of swelling with increasing temperature. Controls indicated that over long time periods, both the MPBA and AAm units were experiencing conversion to different species.
我们在此报告了由20摩尔%的甲基丙烯酰胺基苯硼酸（MPBA）和80摩尔%的丙烯酰胺（AAm）组成、用亚甲基双丙烯酰胺（Bis）轻度交联的水凝胶的溶胀、力学性能和热稳定性的研究。在固定离子强度但pH值和果糖浓度不同的溶液中测量溶胀。通过压缩和保持来研究力学性能。在无糖或存在果糖的情况下，模量在保持期间大多保持不变，而在存在葡萄糖的情况下观察到显著的应力松弛，这与葡萄糖而非果糖提供的可逆动态交联一致。通过在室温、37、50和65°C下于pH 7.4孵育水凝胶并监测溶胀来确定热稳定性。在含有9 mM果糖的磷酸盐缓冲盐水（PBS）溶液中，在室温下溶胀在50天内基本保持完全，但在较高温度下随时间显著降低，且随着温度升高溶胀降低加速。对照表明，在长时间内，MPBA和AAm单元都在经历向不同物种的转化。
