Maintaining dimensions and mechanical properties of ionically crosslinked alginate hydrogel scaffolds in vitro
Maintaining dimensions and mechanical properties of ionically crosslinked alginate hydrogel scaffolds in vitro
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DOI：
10.1002/jbm.a.31375
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发表时间：
2008-03-15
影响因子：
4.9
通讯作者：
Ma, Peter X.
中科院分区：
文献类型：
--
作者：
Kuo, Catherine K.;Ma, Peter X.
离子交联藻酸盐水凝胶是有吸引力的支架，因为它们的生物相容性和温和的凝胶化反应，允许温和的细胞掺入。然而，离子交联水凝胶在水性环境中的不稳定性是限制其应用的挑战。本报告提出了一种新的方法，通过控制介质的离子浓度来控制离子交联水凝胶的尺寸和机械性能。将均匀的藻酸钙凝胶在调节至特定钙离子浓度的生理盐水浴中孵育。溶胀和收缩发生在低和高离子浓度的介质，分别，而“最佳”的中间钙离子浓度的介质被发现保持原来的大小和形状的水凝胶。发现该最佳钙离子浓度是水凝胶的交联密度和聚合物浓度以及藻酸盐的化学组成的函数。最佳和高的钙离子浓度的介质上的溶胀行为，钙含量，干重，和浸泡的水凝胶的机械性能的影响进行了研究。结果发现，所得到的水凝胶组合物和机械性能不仅取决于介质的钙浓度，而且取决于凝胶的交联密度和聚合物浓度。在为期8周的实验中，证明了藻酸盐凝胶在水性环境中的受控尺寸和机械性能。这项新技术显著增强了藻酸盐水凝胶在组织工程和其他生物医学应用中的潜力。(C)2007 Wiley Periodicals，Inc.
Ionically crosslinked alginate hydrogels are attractive scaffolds because of their biocompatibility and mild gelation reaction that allows for gentle cell incorporation. However, the instability of ionically crosslinked hydrogels in an aqueous environment is a challenge that limits their application. This report presents a novel method to control the dimensions and mechanical properties of ionically crosslinked hydrogels via control of the ionic concentration of the medium. Homogeneous calcium-alginate gels were incubated in physiological saline baths adjusted to specific calcium ion concentrations. Swelling and shrinking occurred at low and high ionic concentrations of the medium, respectively, while an "optimal" intermediate calcium ion concentration of the medium was found to maintain original size and shape of the hydrogel. This optimal calcium ion concentration was found to be a function of crosslinking density and polymer concentration of the hydrogel and chemical composition of the alginate. The effects of optimal and high calcium ion concentrations of the medium on swelling behavior, calcium content, dry weight, and mechanical properties of the immersed hydrogels were investigated. It was found that the resulting hydrogel composition and mechanical properties depended on not only the calcium concentration of the medium, but also the crosslinking density and polymer concentration of the gel. In an 8-week experiment, controlled dimensions and mechanical properties of alginate gels in an aqueous environment were demonstrated. This new technique significantly enhances the potential of alginate hydrogels for tissue engineering and other biomedical applications. (C) 2007 Wiley Periodicals, Inc.