Chen Kaiwen, Ying Qiwei, Hao Xingxing, Sun Kai, Wang Huanan
Key State Laboratory of Fine Chemicals, School of Bioengineering, Dalian University of Technology, No. 2 Linggong Road, High-tech District, Dalian, 116024, P.R. China.
Int J Bioprint. 2021 Jun 25;7(3):377. doi: 10.18063/ijb.v7i3.377. eCollection 2021.
A hydrogel that combines both printability and adaptability, high elasticity, and stretchability can provide ideal mechanical properties, and also render complex and accurate construction for ionic skin. However, it is extremely challenging. Here, we propose a colloidal-based double-network (DN) hydrogel as printable inks for high-precision fabrication of ionic skins. Particularly, polyacrylamide (PAAm), as the covalent network that can maintain the long-term material integrity, was combined with gelatin colloidal network to improve the injectability and printability of the resulting DN hydrogels. The DN design cooperatively provides the hydrogels with higher toughness values and deformability than what single colloidal or PAAm network can achieve. Further design of ionic skin based on capacitor microarray was demonstrated to serve as a sensitive and stable capacitor that can respond to external stimuli, thereby allowing to sense the body movements such as finger bending, laugh, and wrist pulse by translating mechanical changes into electric signals. Therefore, this study provides a novel strategy for the design and preparation of high-resolution ionic skins as the wearable sensor.
一种兼具可打印性与适应性、高弹性和拉伸性的水凝胶能够提供理想的机械性能，还能为离子皮肤构建复杂而精确的结构。然而，这极具挑战性。在此，我们提出一种基于胶体的双网络（DN）水凝胶作为用于高精度制造离子皮肤的可打印墨水。特别地，聚丙烯酰胺（PAAm）作为能够维持材料长期完整性的共价网络，与明胶胶体网络相结合，以提高所得DN水凝胶的可注射性和可打印性。DN设计协同为水凝胶提供了比单一胶体或PAAm网络所能实现的更高的韧性值和可变形性。基于电容微阵列的离子皮肤的进一步设计被证明可作为一种灵敏且稳定的电容器，能够响应外部刺激，从而通过将机械变化转化为电信号来感知诸如手指弯曲、大笑和手腕脉搏等身体运动。因此，本研究为作为可穿戴传感器的高分辨率离子皮肤的设计和制备提供了一种新策略。
