Lee Rachel, Hall Emily K, Aljohani Bassam A, McClements Jake, Peeters Marloes, Geoghegan Mark
School of Engineering, Newcastle University, Newcastle-Upon-Tyne, NE1 7RU, UK.
AkzoNobel, Stoneygate Lane, Gateshead, NE10 0JY, UK.
J Mater Sci Mater Med. 2025 Jul 14;36(1):59. doi: 10.1007/s10856-025-06878-3.
Hyaluronic acid was crosslinked using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide to form hydrogels with low elastic modulus. These hydrogels were swollen in water and the elastic modulus was obtained with a contact mechanics approach in ambient conditions using a low-load mechanical tester under compression. The modulus was measured during both the approach and retraction of the cylindrical probe into the gel and was found to be of the order of 30 kPa. The modulus was also measured from a stress-strain curve (47 kPa), in reasonable agreement with the contact mechanics approach. However, nanoindentation and rheology measurements reveal much smaller moduli, indicating that the technique used interrogates different length scales within the gel. This has profound implications for the applications of hydrogels used, for example, in tissue engineering. The values reported here are likely to be appropriate for applications where contact with the spinal cord is necessary. It is argued that a contact mechanics approach is appropriate for the characterization of hydrogels for applications designed for contact with tissue.
使用1-乙基-3-(3-二甲基氨基丙基)碳二亚胺和N-羟基琥珀酰亚胺对透明质酸进行交联，以形成具有低弹性模量的水凝胶。这些水凝胶在水中溶胀，并在环境条件下使用低负荷机械测试仪通过接触力学方法在压缩状态下获得弹性模量。在圆柱形探头进入凝胶的接近和缩回过程中均测量模量，发现其量级为30kPa。还从应力-应变曲线测量了模量（47kPa），与接触力学方法合理一致。然而，纳米压痕和流变学测量显示模量要小得多，这表明所使用的技术探测的是凝胶内不同的长度尺度。这对于例如在组织工程中使用的水凝胶的应用具有深远影响。此处报告的值可能适用于需要与脊髓接触的应用。有人认为，接触力学方法适用于表征设计用于与组织接触的应用的水凝胶。
