Tuning properties of injectable hydrogel scaffold by PEG blending
Tuning properties of injectable hydrogel scaffold by PEG blending
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通过 PEG 混合调节可注射水凝胶支架的性能
DOI：
10.1016/j.polymer.2012.08.054
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发表时间：
2012-10-12
期刊：
影响因子：
4.6
通讯作者：
Zhang, Yongjun
中科院分区：
文献类型：
--
作者：
Cheng, Dan;Wu, Yuhan;Zhang, Yongjun
我们以前表明，聚（N-异丙基丙烯酰胺）（PNIPAM）微凝胶分散体在适当的条件下热凝胶和原位形成的水凝胶可用于三维细胞培养。为了进一步提高其性能，在这里，我们通过与聚（乙二醇）（PEG）共混来定制水凝胶的性能。不含盐的微凝胶/PEG混合物在加热时不胶凝，然而，它们在生理pH和离子强度下胶凝。凝胶化温度随PEG含量的增加而降低，这归因于微凝胶的体积相变温度降低，以及由于PEG链的存在而引起的耗尽吸引。与纯PNIPAM水凝胶相比，共混水凝胶表现出较低的机械强度（单因素方差分析，P < 0.05），然而，PEG共混减少甚至完全防止了水凝胶的脱水收缩。将HepG 2细胞接种并培养在共混水凝胶中。虽然细胞在纯PNIPAM水凝胶中不生长，但它们在含有0.75重量% PEG的共混物水凝胶中生长得非常好（单因素ANOVA，P < 0.05）。因为其脱水收缩减少。进一步增加PEG含量导致细胞-支架相互作用减少，这又导致细胞生长速率降低。PEG含量也影响支架内形成的多细胞球体的形态。在含有0.75wt%PEG的水凝胶中形成紧凑的球状体，而在具有较高PEG含量的水凝胶中形成松散且较小的球状体。我们的研究结果表明，物理共混可以是一个简单而有效的方法来微调可注射水凝胶支架的性能。(C)2012爱思唯尔有限公司保留所有权利。
We previously showed that poly(N-isopropylacrylamide) (PNIPAM) microgel dispersions thermally gel under proper conditions and the in situ-formed hydrogels can be used for 3D cell culture. To further improve their performance, here we tailor the properties of the hydrogels by blending with poly(ethylene glycol) (PEG). The microgel/PEG mixtures containing no salt do not gel upon heating, however, they gel at physiological pH and ionic strength. The gelation temperature decreases with increasing PEG content, which was attributed to the decreased volume phase transition temperature of the microgel, and also depletion attraction because of the presence of PEG chains. Compared with the pure PNIPAM hydrogel, the blend hydrogels exhibit a lower mechanical strength (one-way ANOVA, P < 0.05), however, the syneresis of the hydrogel is reduced or even totally prevented by PEG blending. HepG2 cells were seeded and cultured in the blend hydrogels. While the cells do not grow in pure PNIPAM hydrogels, they grow very well in the blend hydrogel containing 0.75 wt% PEG (one-way ANOVA, P < 0.05). because of its reduced syneresis. Further increasing PEG content results in reduced cell-scaffold interaction, which in turn results in decreased cell growth rate. PEG content also influence the morphology of the multicellular spheroids formed inside the scaffold. Compact spheroids form in hydrogel containing 0.75 wt% PEG, while looser and smaller spheroids form in hydrogels with higher PEG content. Our results indicate physical blending can be a simple but effective method to finely tune the properties of injectable hydrogel scaffolds. (C) 2012 Elsevier Ltd. All rights reserved.