Injection moulded microneedle sensor for real-time wireless pH monitoring

• Published in: 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) Vol. 2017; pp. 189 - 192
• Main Authors: Mirza, Khalid B., Zuliani, Claudio, Hou, Benjamin, Fu Siong Ng, Peters, Nicholas S., Toumazou, Christofer
• Format: Conference Proceeding Journal Article
• Language: English
• Published: United States IEEE 01-07-2017
• Subjects: Animals; Electrodes; Electroplating; Heart; Hydrogen-Ion Concentration; Injection molding; Injections; Male; Needles; Potentiometry; Rats; Rats, Wistar; Real-time systems; Time Factors; Wireless communication; Wireless sensor networks; Wireless Technology
• ISSN: 1557-170X; 2694-0604
• DOI: 10.1109/EMBC.2017.8036794

This paper describes the development of an array of individually addressable pH sensitive microneedles using injection moulding and their integration within a portable device for real-time wireless recording of pH distributions in biological samples. The fabricated microneedles are subjected to gold patterning followed by electrodeposition of iridium oxide to sensitize them to 0.07 units of pH change. Miniaturised electronics suitable for the sensors readout, analog-to-digital conversion and wireless transmission of the potentiometric data are embodied within the device, enabling it to measure real-time pH of soft biological samples such as muscles. In this paper, real-time recording of the cardiac pH distribution, during ischemia followed by reperfusion cycles in cardiac muscles of male Wistar rats has been demonstrated by using the microneedle array.