Son Kuk Hui, Lee Jin Woo
Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, 34, Namdong-daero 774beon-gil, Namdong-gu, Incheon 21565, Korea.
Department of Molecular Medicine, School of Medicine, Gachon University, 155 Gaetbeol-ro, Yeonsu-ku, Incheon 21999, Korea.
Materials (Basel). 2016 Oct 20;9(10):854. doi: 10.3390/ma9100854.
The swelling properties and thermal transition of hydrogels can be tailored by changing the hydrophilic-hydrophobic balance of polymer networks. Especially, poly(-isopropylacrylamide) (PNIPAm) has received attention as thermo-responsive hydrogels for tissue engineering because its hydrophobicity and swelling property are transited around body temperature (32 °C). In this study, we investigated the potential of poly(ethylene glycol) diacrylate (PEGDA) as a hydrophilic co-monomer and crosslinker of PNIPAm to enhance biological properties of PNIPAm hydrogels. The swelling ratios, lower critical solution temperature (LCST), and internal pore structure of the synthesized p(NIPAm--PEGDA) hydrogels could be varied with changes in the molecular weight of PEGDA and the co-monomer ratios (NIPAm to PEGDA). We found that increasing the molecular weight of PEGDA showed an increase of pore sizes and swelling ratios of the hydrogels. In contrast, increasing the weight ratio of PEGDA under the same molecular weight condition increased the crosslinking density and decreased the swelling ratios of the hydrogels. Further, to evaluate the potential of these hydrogels as cell sheets, we seeded bovine chondrocytes on the p(NIPAm--PEGDA) hydrogels and observed the proliferation of the seed cells and their detachment as a cell sheet upon a decrease in temperature. Based on our results, we confirmed that p(NIPAm--PEGDA) hydrogels could be utilized as cell sheets with enhanced cell proliferation performance.
通过改变聚合物网络的亲水-疏水平衡，可以调整水凝胶的溶胀特性和热转变。特别是，聚（N-异丙基丙烯酰胺）（PNIPAm）作为用于组织工程的热响应性水凝胶受到关注，因为其疏水性和溶胀特性在体温（32°C）左右会发生转变。在本研究中，我们研究了聚乙二醇二丙烯酸酯（PEGDA）作为PNIPAm的亲水性共聚单体和交联剂以增强PNIPAm水凝胶生物学特性的潜力。合成的p（NIPAm-PEGDA）水凝胶的溶胀率、低临界溶液温度（LCST）和内部孔结构会随着PEGDA分子量和共聚单体比例（NIPAm与PEGDA）的变化而改变。我们发现增加PEGDA的分子量会使水凝胶的孔径和溶胀率增加。相反，在相同分子量条件下增加PEGDA的重量比会增加交联密度并降低水凝胶的溶胀率。此外，为了评估这些水凝胶作为细胞片的潜力，我们将牛软骨细胞接种在p（NIPAm-PEGDA）水凝胶上，并观察种子细胞的增殖以及温度降低时它们作为细胞片的脱离情况。基于我们的结果，我们证实p（NIPAm-PEGDA）水凝胶可作为具有增强细胞增殖性能的细胞片使用。
