A highly linear stretchable MXene-based biocompatible hydrogel-elastomer hybrid with tissue-level softness

一种具有组织级柔软度的高线性可拉伸的MXene基生物相容性水凝胶–弹性体混合物

Maintaining low modulus while endowing the wide-range linear stretchability to wearable or implantable devices is crucial for these devices to reduce the mechanical mismatch between the devices and human skin/tissue interfaces.However,improving linear stretchability often results in an increased modulus of stretchable electronic materials,which hinders their conformability in long-term quantifiable monitoring of organs.Herein,we develop a hybrid structure involving interlocking low-modulus porous elastomers(Ecoflex-0030)and MXene-based hydrogels with crosslinking networks of polyvinyl alcohol,sodium alginate,and MXene.This hydrogel–elastomer structure exhibits superior performance compared with previous reports,with a wide linear stretchability strain range from 0 to 1000%and maintaining a low modulus of 6.4 kPa.Moreover,the hydrogel–elastomer hybrids can be utilized as highly sensitive strain sensors with remarkable characteristics,including high sensitivity(gauge factor~3.52),a linear correlation between the resistance and strain(0–200%),rapid response(0.18 s)and recovery times(0.21 s),and excellent electrical reproducibility(1000 loading–unloading cycles).Those electrical and mechanical properties allow the sensor to act as a suitable quantifiable equipment in organ monitoring,human activities detecting,and human–machine interactions.

为减少与人体皮肤/组织界面之间的机械失配,可穿戴/植入式设备在具有大线性拉伸性的同时保持低模量至关重要.然而,改善线性拉伸性往往会导致可拉伸材料模量的增加,这会阻碍它们在长期器官定量监测中的共形性.为此,我们开发了一种混合结构:互锁的低模量多孔弹性体(Ecoflex-0030)/MXene基水凝胶.这种水凝胶–弹性体结构表现出更优异的性能,具有从0到1000%的大线性拉伸应变范围和6.4 kPa的低模量.此外,水凝胶–弹性体混合物可用作高灵敏度应变传感器,具有高灵敏度(GF~3.52)、线性电阻(0–200%)、快速响应(0.18 s)/恢复时间(0.21 s),以及优异的可重复性(1000次加载–卸载循环).这使得该器件在器官监测、人体活动监测和人机交互方面具有巨大的潜力.