Yeung, Jonas – Integration of polyaniline wire sensor in microfluidic devices for biosensors (Dr. Ravi Selvaganapathy)

Biosensors have attracted a considerable amount of attention due to their applications in clinical and environmental settings. For instance, glucose meters are biosensors used among diabetic patients to monitor blood glucose levels. Hence, there is an increased need for creating biosensors that are more affordable with improved efficacy. There have been significant efforts integrating microfluidic systems with biosensors. Microfluidics devices allow the manipulation of small amounts of fluids, with microchannels serving as small pipes. These devices have the ability to mimic repetitive laboratory methods in a miniaturized system. Advantages include a reduction in the sample, energy, reagent consumption, and waste production. The aim of this project is to integrate wire sensing technology into a microfluidic device. The benefits would be higher sensitivity due to the increased surface area and the possibility of detecting multiple parameters simultaneously. Two biosensor and microfluidic concepts were investigated in this study. First, palladium wires were oxidized to create palladium oxide electrodes that are known to have pH sensing properties. The wire’s open circuit potential was tested with a Ag/Cl reference electrode from pH levels ranging from 3 to 8. A calibration curve for the wires were plotted and gave an average slope of around -40 mV/pH, which is near the predicted value of -50 mV/pH given by the Nernst equation. Secondly, the wires were integrated in a microfluidic device to detect pH with a small volume of solution. Therefore, this device demonstrates the innovative approach of integrating biosensing technology into microfluidic devices.