The need for spatially-confined electrical stimulation is growing in biomedical applications,for example intracorticalstimulation and retinal implant,for enhancement of stimulating resolution.Local grounding technique...The need for spatially-confined electrical stimulation is growing in biomedical applications,for example intracorticalstimulation and retinal implant,for enhancement of stimulating resolution.Local grounding techniques have beenwidely explored to suppress undesired current spread.However,in conventional microneedle arrays like the Utaharray,grounding is typically achieved by assigning neighboring electrodes as ground or employing grounding wallaround stimulating electrode,which compromises spatial efficiency.In this work,we introduce,for the first time,abipolar microneedle electrode array(BMEA)that integrates two electrically-independent electrodes within each threedimensionalmicroneedle structure.The microtip electrode,located at the apex of the microneedle,delivers electricalstimulation,while the local ground electrode,embedded on the sidewall below the microtip,serves to locally confinethe spread of current.COMSOL Multiphysics simulations and ex vivo experiments using isolated mouse retinademonstrated that activating the local ground electrode effectively restricts current diffusion,enabling more focusedand localized stimulation.This approach offers a compact and efficient solution for focal electrical stimulation withenhanced spatial resolution,providing a promising platform for advanced neural interfacing systems in variousbiomedical fields.展开更多
基金supported in part by KIST(Korea Institute of Science and Technology)institutional grants(Nos.2E33881 and 2E33682)in part by the National R&D Program through the National Research Foundation(NRF)of Korea,funded by the Ministry of Science and ICT(Nos.2023R1A2C2003786,RS-2023-00302397,RS-2025-25465381,and RS-2025-00514523).
文摘The need for spatially-confined electrical stimulation is growing in biomedical applications,for example intracorticalstimulation and retinal implant,for enhancement of stimulating resolution.Local grounding techniques have beenwidely explored to suppress undesired current spread.However,in conventional microneedle arrays like the Utaharray,grounding is typically achieved by assigning neighboring electrodes as ground or employing grounding wallaround stimulating electrode,which compromises spatial efficiency.In this work,we introduce,for the first time,abipolar microneedle electrode array(BMEA)that integrates two electrically-independent electrodes within each threedimensionalmicroneedle structure.The microtip electrode,located at the apex of the microneedle,delivers electricalstimulation,while the local ground electrode,embedded on the sidewall below the microtip,serves to locally confinethe spread of current.COMSOL Multiphysics simulations and ex vivo experiments using isolated mouse retinademonstrated that activating the local ground electrode effectively restricts current diffusion,enabling more focusedand localized stimulation.This approach offers a compact and efficient solution for focal electrical stimulation withenhanced spatial resolution,providing a promising platform for advanced neural interfacing systems in variousbiomedical fields.
