Hydrogen Ion Image Sensor with Barrel Array Diffusion Suppressor and Hippocampal Slice Imaging

An ion image sensor is an important tool to chemically and dynamically observe the two-dimensional information of a living body. However, its spatial resolution is limited because it does not have any element that prevents the diffusion of target ion like a focusing lens used in optical image sensors. This paper proposes a novel approach to enhance spatial resolution of the ion image sensor for the first time. We introduce a barrel array to suppress the lateral diffusion of target ion on the surface of ion image sensor. This micro barrel array with high aspect ratio was fabricated on the ion image sensor using SU-8. By measuring the hippocampal slice for 10 min, H
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diffusion was suppressed as compared to the ion image sensor without diffusion suppressor. The ion image sensor has lately become popular in the microscopic analysis of biological tissue in high resolution owing to the proposed diffusion suppressor.