| Hydrogel is a new kind of biomaterial with good biocompatibility,high water content and softness.However,the traditional hydrogels usually have the disadvantages of single function,poor mechanical properties and electrical conductivity,which greatly limit their applications.Metal-organic framework(MOF)is composed of metal-based nodes and organic molecular linkers.MOF has many advantages,such as adjustable porosity,good chemical stability,ultra-high specific surface area and adjustable surface chemistry.Therefore,MOF has a wide range of applications in the field of heterogeneous catalysis,energy storage,gas storage and separation,and electrochemical sensing.Especially in the field of biomedical engineering,MOFs based biomaterials have great potential in drug sustained-release,photodynamic therapy,wound healing,biological imaging and biosensors.However,due to the poor electrical conductivity and water dispersion of most MOFs materials,it is difficult for MOFs materials to be used in practice.To solve the above problems,this study designed a multi-functional musselinspired MIL-53(Fe)and polydopamine reduced graphene oxide(MIL-53@PGO)complex with good electrical conductivity,adhesion and biocompatibility.We used the MIL-53@PGO as a nanofiller to prepare a multi-functional adhesive and conductive hydrogel.The specific content can be divided into the following parts:(1)The natural mussel like material polydopamine was used to partially reduce GO to obtain dopamine-modified graphene.On the one hand,the number of sp2 bonded carbon sites of GO was increased by the reduction of pre-dopamine,thus improving the electron transport capacity of GO;On the other hand,the introduction of dopamine provided a large number of active sites on the GO surface.Next,hydrothermal synthesis of metal organic framework MIL-53 modification of graphene nanoparticles and dopamine,first phenolic hydroxyl groups on the surface of the dopamine can improve the water dispersion of MIL-53 nanoparticles,and secondly phenol hydroxyl groups makes the hydrogels have great adhesiveness.Therefore,MIL-53@PGO nanoparticles can be introduced into the polyacrylamide hydrogels as nano fillers,giving the hydrogels good conductivity and adhesion.(2)MIL-53(Fe)has high porosity,large specific surface area,the structure and functional advantages of adjustable,can be a great potential material for development of energy storage material,because this solved the problem of poor electric conductivity of hydrogel,and this hydrogel exhibited better capacitor performance than the single MOF and single PGO hydrogel.(3)In this paper,the cell regulation behavior and biocompatibility of MIL-53@PGO polyacrylamide hydrogel were explored through cell experiments and animal experiments.Because of the good electrical conductivity of the hydrogel,it can be used for electrical stimulation to regulate cell behavior.Under different voltage stimulation(0m V,300 m V,600 m V,900 m V),the adhesion,spread and proliferation of cells on the hydrogel were observed.In addition,the in vivo experiment showed that the hydrogel has good biocompatibility due to the presence of catechol functional group on MIL-53@PGO.In summary,we prepared a multifunctional MIL-53@PGO hydrogel with adhesion,conductivity and good biocompatibility by miming mussel chemistry.This hydrogel can be used as an implantable electrode for the detection of biological signals in vivo,which has great potential in the fields of biosensors,wearable devices and implantable bioelectronics.At the same time,it has good biocompatibility for wound healing. |
