Hydrogen Ion Microscope Using 2 µM Pitch pH Image Sensor for Analysis of Mouse Hippocampal Slice

We have developed a novel ion image sensor with a fine pixel pitch, which is shorter than one-tenth of the 23.55 μm in the previous design. In this report, we highlight the imaging potential of a 2-μm-pitch ion image sensor in the measurement of the neural activity of mouse hippocampus. This pitch is sufficiently small to observe the action of a single cell. The results of brain-slice imaging indicated that the diffusion of H+ ions was different in each region containing CA1, CA2, and DG in the hippocampus. In addition, the sensor clearly captured the distribution of neural cell responses.