A microplate compression method for elastic modulus measurement of soft and viscoelastic collagen microspheres
A microplate compression method for elastic modulus measurement of soft and viscoelastic collagen microspheres
复制标题
DOI：
10.1007/s10439-008-9507-y
复制
发表时间：
2008-07-01
影响因子：
3.8
通讯作者：
Ngan, A. H. W.
中科院分区：
文献类型：
--
作者：
Chan, B. P.;Li, C. H.;Ngan, A. H. W.
基于水凝胶的微球通常用于再生医学中的药物和细胞递送。它们的物理和机械性能的表征对于在制造过程中监测它们的质量和预测它们在注射时的性能是重要的。然而，现有的方法在测量这些微米级的、柔软的和粘弹性的球形结构方面具有局限性。在这项研究中，开发了一个协议，以测量非线性粘弹性微球的弹性模量的微孔板压缩，并适用于胶原微球制造或不含细胞。在测量过程中，将微球放置在刚性表面上，并通过夹持到刚性端的校准的柔性微孔板压缩。一个步骤增加的刚性端的柔性微板的位移速率的引入和减少的弹性模量的微球的计算从微球的变形响应，使用本研究中导出的方程。通过该方法测量的含有和不含间充质干细胞的胶原微球的折合弹性模量分别为9.1kPa和132Pa。
Hydrogel-based microspheres are commonly used for drug and cell delivery in regenerative medicine. Characterization of their physical and mechanical properties is important in monitoring their quality during fabrication and in predicting their performance upon injection. However, existing methods have limitations in measuring these micron-sized, soft and viscoelastic spherical structures. In this study, a protocol is developed to measure the elastic modulus of non-linear viscoelastic spheres by microplate compression, and is applied to collagen microspheres fabricated with or without cells. During the measurement, a microsphere is placed on a rigid surface and is compressed by a calibrated flexible microplate gripped to a rigid end. A step increase in the displacement rate of the rigid end of the flexible microplate is introduced and the reduced elastic modulus of the microsphere is calculated from the deformation response of the microsphere, using an equation derived in this study. The reduced elastic modulus of collagen microspheres with and without mesenchymal stem cells measured by this method was 9.1 kPa and 132 Pa, respectively.