Signal drift and performance instability of brain-computer interface devices induced by the interface failure between rigid metal electrodes and soft human skin hinder the precise data acquisition of electroencephalog...Signal drift and performance instability of brain-computer interface devices induced by the interface failure between rigid metal electrodes and soft human skin hinder the precise data acquisition of electroencephalogram(EEG).Thus,it is desirable to achieve a robust interface for brain-computer interface devices.Here,a kind of polydopamine methacrylamide-polyacrylamide(PDMA-PAAM)hydrogel is developed.To improve the adhesion,dopamine is introduced into the polyacrylamide hydrogel,through the amino and catechol groups of dopamine in an organic-inorganic interface to build a covalent and non-covalent interaction.A strong attachment and an effective modulus transition system can be formed between the metal electrodes and human skin,so that the peeling force between the PDMAPAAM hydrogel and the porcine skin can reach 22 N m^(-1).In addition,the stable conductivity and long-term operating life of the PDMA-PAAM hydrogel for more than 60 days at room temperature are achieved by adding sodium chloride(NaCl)and glycerol,respectively.The PDMA-PAAM hydrogel membrane fabricated in this work is integrated onto a flexible Au electrode applied in a brain-computer interface.In comparison,the collected EEG signal intensity and waveform are consistent with that of the commercial counterparts.And obviously,the flexible electrode with PDMA-PAAM hydrogel membrane is demonstrated to enable a more stable and userfriendly interface.展开更多
基金supported by the National Natural Science Foundation of China(U20A6001,11921002,and 11902292)Zhejiang Province Key Research and Development Project(2021C01183,2020C05004,and 2021C05007-4)the Natural Science Foundation of Zhejiang Province of China(LQ19E030003)。
文摘Signal drift and performance instability of brain-computer interface devices induced by the interface failure between rigid metal electrodes and soft human skin hinder the precise data acquisition of electroencephalogram(EEG).Thus,it is desirable to achieve a robust interface for brain-computer interface devices.Here,a kind of polydopamine methacrylamide-polyacrylamide(PDMA-PAAM)hydrogel is developed.To improve the adhesion,dopamine is introduced into the polyacrylamide hydrogel,through the amino and catechol groups of dopamine in an organic-inorganic interface to build a covalent and non-covalent interaction.A strong attachment and an effective modulus transition system can be formed between the metal electrodes and human skin,so that the peeling force between the PDMAPAAM hydrogel and the porcine skin can reach 22 N m^(-1).In addition,the stable conductivity and long-term operating life of the PDMA-PAAM hydrogel for more than 60 days at room temperature are achieved by adding sodium chloride(NaCl)and glycerol,respectively.The PDMA-PAAM hydrogel membrane fabricated in this work is integrated onto a flexible Au electrode applied in a brain-computer interface.In comparison,the collected EEG signal intensity and waveform are consistent with that of the commercial counterparts.And obviously,the flexible electrode with PDMA-PAAM hydrogel membrane is demonstrated to enable a more stable and userfriendly interface.