Mechanical behaviour of alginate-gelatin hydrogels for 3D bioprinting
Mechanical behaviour of alginate-gelatin hydrogels for 3D bioprinting
复制标题
DOI：
10.1016/j.jmbbm.2017.12.018
复制
发表时间：
2018-03-01
影响因子：
3.9
通讯作者：
Doyle, Barry J.
中科院分区：
文献类型：
--
作者：
Di Giuseppe, Michael;Law, Nicholas;Doyle, Barry J.
由海藻酸盐和明胶组成的水凝胶在三维生物打印应用中显示出潜在的生物材料的潜力。然而，与所有用于挤压生物打印的水凝胶生物材料一样，许多参数会影响它们的性能，而且描述藻酸盐-明胶(Alg-Gel)水凝胶行为的数据有限。在这里，我们通过改变不同的组成浓度来研究九种Alg-Gel混合物。我们测试了生物打印结构中包裹的间充质干细胞的打印性能和打印精度、压缩行为和随时间的变化以及活性。打印性能测试显示，随着Alg-Gel浓度的增加，链宽度减小。然而，由于较高的Alg-Gel浓度导致粘度增加，在混合物变得太粘而无法打印之前，最小宽度被发现为0.32 mm。同样，在较高浓度下，打印精度提高，在某些混合物中超过90%。通过单轴压缩试验评估了材料的力学性能，发现Alg和Gel浓度的增加都会导致较高的压缩弹性系数。我们也认为在氯化钙中15分钟的交联性是足够的。从我们的数据，我们建议7%的Alg-8%的凝胶混合物，产生高印刷性，机械强度和硬度，以及细胞活力。然而，我们发现Alg-Gel的压缩行为随着时间的推移而迅速下降，特别是在37℃孵化时。这里我们报告了用于生物打印的Alg-Gel水凝胶的相关数据。我们测试了生物材料的性能，并表明这些水凝胶具有许多高度可调的理想特性。尽管在实现在体内的实际应用之前还需要进一步的工作。
Hydrogels comprised of alginate and gelatin have demonstrated potential as biomaterials in three dimensional (3D) bioprinting applications. However, as with all hydrogel-based biomaterials used in extrusion-based bioprinting, many parameters influence their performance and there is limited data characterising the behaviour of alginate-gelatin (Alg-Gel) hydrogels.Here we investigated nine Alg-Gel blends by varying the individual constituent concentrations. We tested samples for printability and print accuracy, compressive behaviour and change over time, and viability of encapsulated mesenchymal stem cells in bioprinted constructs.Printability tests showed a decrease in strand width with increasing concentrations of Alg-Gel. However due to the increased viscosity associated with the higher Alg-Gel concentrations, the minimum width was found to be 0.32 mm before blends became too viscous to print. Similarly, printing accuracy was increased in higher concentrations, exceeding 90% in some blends. Mechanical properties were assessed through uniaxial compression testing and it was found that increasing concentrations of both Alg and Gel resulted in higher compressive modulus. We also deemed 15 min crosslinking in calcium chloride to be sufficient. From our data, we propose a blend of 7%Alg-8%Gel that yields high printability, mechanical strength and stiffness, and cell viability. However, we found the compressive behaviour of Alg-Gel to reduce rapidly over time and especially when incubated at 37 degrees C.Here we have reported relevant data on Alg-Gel hydrogels for bioprinting. We tested for biomaterial properties and show that these hydrogels have many desirable characteristics that are highly tunable. Though further work is needed before practical use in vivo can be achieved.