Liquid-solid Macromolecular Electrostatic Interaction Enabling Self-adaptive Adhesion Of Hydrogel Biosensors

Purpose: Hydrogels have been widely used in the field of biosensors due to their high elasticity and stimulus response.However,conventional bioelectronics usually do not conform well with natural skin surfaces and are susceptible to motion artifact interference,due to incompatible dimensions,insufficient adhesion and imperfect compliance,which greatly limit the application range of hydrogel biosensors.Therefore,to develop an effective strategy to achieve adaptive adhesion of different interfaces is of great significance in expanding the development of hydrogels in the field of sensors.We will focus on the interinterface.Method: In this paper,we have reported a liquid-solid synergistic protocol to enable the self-adaptive adhesion of hydrogel sensors at various surfaces to address the challenge above.The superiority of this protocol was that the hydrogel sensor was formed in situ,in which the liquid element could work as glue to combine the formed hydrogel sensor with the tested surface.The interfacial combination together with ultra-thin thickness enabled the self-adaptive adhesion of the hydrogel sensor.Results: In this paper,the hydrogel sensor was prepared through the liquid-solid macromolecular system,and its construction,mechanical properties,electrical properties and biocompatibility were studied,and the following innovative achievements were obtained: 1.In-situ forming hydrogel sensors with adaptive adhesion on different surfaces were obtained,and adaptive adhesion between hydrogel network and bonding surface was realized at the molecular level to overcome micron or even larger gaps,such as micron wrinkles and pores;2,hydrogel sensor can well withstand reversible deformation in the process of motion,and produce regular electrical signals;3.It was found that hydrogels based on dopamine derivatives of alginate could effectively regulate the adhesion/disadhesion of hydrogels at the interface through p H regulation,and could easily erase hydrogels.Conclusion: We have demonstrated that our hydrogel showed a promising biosensing capability at various surfaces.We thus hope that the liquid-solid synergistic protocol could open a more available pathway for in-situ formation of hydrogel sensor for the physiological signal monitoring of organisms.