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This paper presents a standalone system based on the Raspberry Pi miniature computer capable of ion-imaging and visualisation using a CMOS chemical sensing array. The sensory part utilises a $64\times 200$ ISFET-based array biased in velocity saturation that achieves high linearity in its input-output characteristics (pH-current). The system consists of a Raspberry Pi and custom PCB board and allows high portability at a low overall cost. As a result, it constitutes a portable platform capable of real-time ion sensing and visualisation. The achieved frame rate is 10FPS maximum or limited to 5FPS with real-time visualisation of the 12,800 pixel array. Moreover, we show the simultaneous and real-time calibration and readout of the ISFET array, reducing the mismatches between pixels due to uneven trapped charge, without any impact on the performance. Demonstrations further show that the system can detect changes in pH and capture visuals of dynamic ion concentration changes in a solution. Ion imaging captured at 5FPS shows HCl diffusion in a de-ionized water solution showcasing the spatial changes in the ion concentration. This constitutes a promising approach for the realisation of ion imaging platforms and portable Point-of-Care diagnostic systems using ISFET arrays.

This demonstration presents a portable and low-power ISFET platform, powered by a solar panel battery system. A 32x32 ISFET array is connected to the portable platform using a custom cartridge, which interface with a Raspberry Pi that controls biasing, configuration and data acquisition, while displaying the results on a touchscreen. Inspired by classic videogame consoles, we present a GUI for screening and diagnosis which provides an intuitive experience for non-expert users, ultimately offering an end-to-end system for ISFET-based Point-of-Care diagnosis.

A portable and low-cost system capable of high-speed ion-imaging using ISFET arrays will be demonstrated. The system takes advantage of the portability and processing power of Raspberry Pi, enabling high-speed measurements from a large-scale ISFET array. This array contains 64×200 ISFET pixels and is connected to a custom PCB that provides analogue-to-digital conversion as well as configuration signals. This platform offers a complete solution allowing ion-imaging and pH observations outside of the lab environment. We anticipate that this efficient approach holds significant potential for affordable ion-imaging systems, making them more readily available for further research.