A cost effective, self-calibrating, low maintenance pH sensor for an integrated approach to monitoring sea and drinking water, facilitating improvements in ocean, animal and human health and water resource management.
Funded by H2020 SMEi Programme
Project duration 24 months, started August 2018
ANB Sensors (ANB) is developing the next generation of pH Sensors for oceanographic, environmental and water resource management applications.
The key failing of existing pH sensors, and more generally most if not all Ion Selective Electrodes (ISEs) is the short life and high maintenance costs of the sensors because of reference electrode drift, which is the gradual change in the reference potential over time, causing some sensors to be thrown away within two weeks of operation. Clearly, a sensor can only make accurate measurements if the reference potential, which is what all sensor measurements are made against, is stable.
The impact of reference drift is that most ISE sensors cannot be used for long duration monitoring, cannot be used autonomously in smart sensor networks and, most critically, require frequent, labour intensive, costly manual calibration, which adds up to 70% of the total purchase and operation cost of the ISE sensor. The inability of existing pH sensors to operate in autonomous networks, means that pH, the most fundamental of measurements, cannot be effectively monitored in smart networks/big data systems.
ANB’s innovative pH sensor, the pHenom, is based on a voltammetric electrochemical technique, which utilises a pH responding molecule bound within a solid-state matrix. This is combined with a novel means of verifying the performance of the pHenom’s reference electrode, through an additional in-situ electrochemical measurement. The in-situ measurement is used to calibrate the reference electrode, removing the need for manual calibration and making the pHenom capable of drift free pH measurement, and thus capable of operation without costly manual calibration and suitable for use in autonomous, smart networks.
ANB’s overall objective for this project is to develop the pHenom technology to the point where it can be launched in the market, through technology licensing and sales. To meet this objective, ANB propose in this project to develop and produce three (3) calibration free commercial prototype sensor systems (one glass pH sensor system, one ISE system and one pHenom system for use on AUV’s). At this point, each of the commercial prototypes will be specifically tailored for the biggest pH sensor markets, the water (ocean) monitoring and management industries. These commercial prototypes will be used to demonstrate the operational advantages of the pHenom technology and to gain market acceptance from prospective licensees and end-users.