It has attracted much attention to develop a gradient hydrogel for real mimic of the extracellular matrix. Despite simplicity and ease of electrophoresis preparation method, some drawbacks limit the application of the method including toxic organic crosslinker residual, specific ionic monomer types, as well as narrow gradient gaps. In this work, we successfully prepared gradiently crosslinked nonionic PNIPAm/Laponite nanocomposite (NC) hydrogels with controllable gradient structures by adjusting the intensity of the direct current electric field. The results showed that the stiffness, surface property and thermosensitivity of the hydrogel changed with gradient distributions of Laponite. The average stiffness gradients varied from 0.18 kPa/mm, 0.41 kPa/mm to 1.28 kPa/mm by simply adjusting the intensity of the direct current electric field from 0.13 V/mm, 0.20 V/mm to 0.27 V/mm accordingly. The stiffness reached in a range of 13.8∼33.0 kPa. The growth behaviors of human cervical cancer cells (HeLa cells) on the gradient NC hydrogel surface were discussed. Spreading and proliferation, as well as morphology of HeLa cells were closely related to the stiffness of the gradient NC hydrogels. This work develops a stiffness-controllable gradient NC hydrogel and opens up a new insight into the better understanding of cells behaviors in different tissues and organs in vivo.

开发用于真正模拟细胞外基质的梯度水凝胶已经引起了很多关注。尽管电泳制备方法简单易用，但一些缺点限制了该方法的应用，包括有毒有机交联剂残留、特定的离子单体类型以及窄梯度间隙。在这项工作中，我们通过调节直流电场的强度，成功制备了梯度交联的非离子 PNIPAm/Laponite 纳米复合材料 (NC) 水凝胶，其梯度结构可控。结果表明，水凝胶的刚度、表面性质和热敏性随着合成锂皂石的梯度分布而变化。通过简单地从 0 调整直流电场的强度，平均刚度梯度从 0.18 kPa/mm、0.41 kPa/mm 到 1.28 kPa/mm 不等。13 V/mm、0.20 V/mm 到 0.27 V/mm 相应。刚度达到了 13.8∼33.0 kPa 的范围内。讨论了人宫颈癌细胞（HeLa细胞）在梯度NC水凝胶表面的生长行为。HeLa 细胞的扩散和增殖以及形态与梯度 NC 水凝胶的刚度密切相关。这项工作开发了一种刚度可控的梯度 NC 水凝胶，并为更好地理解不同组织和器官中的细胞行为开辟了新的视角 以及 HeLa 细胞的形态与梯度 NC 水凝胶的刚度密切相关。这项工作开发了一种刚度可控的梯度 NC 水凝胶，并为更好地理解不同组织和器官中的细胞行为开辟了新的视角 以及 HeLa 细胞的形态与梯度 NC 水凝胶的刚度密切相关。这项工作开发了一种刚度可控的梯度 NC 水凝胶，并为更好地理解不同组织和器官中的细胞行为开辟了新的视角体内。