Multi‐Well Sensor Platform Based on a Partially Etched Structure of a Light‐Addressable Potentiometric Sensor

Abstract

A multi‐well‐structured light‐addressable potentiometric sensor (LAPS) plate is developed for measuring a plurality of sample solutions on a single sensor plate. It is also capable of high‐resolution chemical imaging inside the well structure. It can be applied, for example, to quantification of metabolic activities and imaging of biological samples incubated in the well structure. A minimum pattern size of 20 µm line is visualized and a wider frequency bandwidth of up to 200 kHz for the sensor signal is obtained in the well structure, which will be suitable for recording chemical images at a high‐frame‐rate.

Light Addressable Potentiometric Sensors for Biochemical Imaging on Microscale: A Review on Optimization of Imaging Speed and Spatial Resolution

“…The thin substrate can be obtained through decreasing the thickness of the thick Si wafer with physical or chemical method, such as wet etching, − ion etching, , etc. Nakao et al etch n-type Si with KOH to optimize LAPS, where the spatial resolution is improved to 10 μm by etching the n-type Si wafer with hundreds of micrometers thickness to 20 μm .…”

“…Compared with the 40 μm achieved in the frame region, spatial resolution measured in the etched region is improved to 20 μm. In subsequent research, LAPS with a multiwell sensor platform based on the same etching technology as that in ref is designed . As shown in Figure a, there are several etching wells with a depth of 100 μm as the measuring region in a sensor plate.…”

“…(a) Multiwell structure partially etched with TMAH. Reproduced with permission from ref . Copyright 2019 John Wiley and Sons.…”

“…In subsequent research, LAPS with a multiwell sensor platform based on the same etching technology as that in ref 65 is designed. 88 As shown in Figure 5a, there are several etching wells with a depth of 100 μm as the measuring region in a sensor plate. The spatial resolution for LAPS with the multiwell sensor platform is less than 20 μm, which is based on the premise that the thickness of LAPS in the etching well is 47 μm.…”