ELECTROCHEMICAL DETERMINATION OF PH USING PAPER-BASED DEVICES

The research presented in this thesis describes the development of an electrochemical microfluidic paper-based analytical device for pH-sensing. Chapter 2 describes the importance of pH and provides examples of techniques used to measure pH. In Chapter 4, preliminary tests on the electrochemical microfluidic paper-based analytical devices demonstrate the feasibility of pH measurements. Chapter 5 describes three different approaches for modification of the surface of the electrodes painted on the paper-based devices: sodium carbonate, plasma treatment with air, and pure oxygen plasma treatment. Chapter 6 describes changes made to the design of the paper-based devices and the addition of a conditioning step to improve the definition of redox peaks and improve the precision of the method for measuring pH. In Chapter 7, the optimized paper-based device and method are applied to measure the pH of various solutions pH ranging from 1 to 13.