# Sensor ToolKit (STK): Compact Multiplexing Potentiostat for Point-of-Care Applications

## TL;DR

The Sensor ToolKit (STK) is a compact, low-cost electrochemical sensor platform suitable for point-of-care and IoT applications.

## Contribution

A novel, low-cost, and versatile potentiostat platform (STK) with IoT capabilities for distributed electrochemical sensing.

## Key findings

- STK demonstrated excellent analytical performance in detecting potassium, hydrogen peroxide, glucose, and lactate.
- The platform supports wireless data retrieval and real-time visualization using Grafana, suitable for IoT applications.

## Abstract

Embedded potentiostats have enabled the possibility of
implementing
electrochemical applications in a wide range of areas, from industry
to healthcare. However, the optimization for either small size, low-cost
devices, or sensor interfacing in existing platforms may lead to impractical
outcomes. In this work, we propose Sensor ToolKit (STK), prototyped
using off-the-shelf components and engineered to be a highly versatile,
small, and low-cost platform of minimal complexity for the deployment
of distributed IoT electrochemical sensors applications. The board
implements an on-chip sequential input multiplexer that is especially
suited for open-circuit potentiometry studies. The performance of
the board was validated in potentiometric detection of potassium,
hydrogen peroxide, glucose, and lactate, as well as self-current detection
of hydrogen peroxide. Results show excellent analytical performance,
comparable to that of benchtop instrumentation standards. The developed
firmware and IoT framework enable the retrieval of sensor data wirelessly
by a remote data server, which automates its real-time visualization
using the Grafana web application, highlighting the potential of STK
in distributed hyperconnected applications.