Norman Jenkinson

Next generation screen printed electrochemical platforms: Non-enzymatic sensing of carbohydrates using copper(II) oxide screen printed electrodes

The first example of a copper(ii) oxide screen printed electrode is reported which is characterised with microscopy and explored towards the electrochemical sensing of glucose, maltose, sucrose and fructose. It is shown that the non-enzymatic electrochemical sensing of glucose with cyclic voltammetry and amperometry is possible with low micro-molar up to milli-molar glucose readily detectable which compares competitively with nano-catalyst modified electrodes. The sensing of glucose shows a modest selectivity over maltose and sucrose while fructose is not detectable. An additional benefit of this approach is that metal oxides with known oxidation states can be incorporated into the screen printed electrodes allowing one to identify exactly the origin of the observed electro-catalytic response which is difficult when utilising metal oxide modified electrodes formed via electro-deposition techniques which result in a mixture of metal oxides/oxidation states. These next generation screen printed electrochemical sensing platforms provide a simplification over previous copper oxide systems offering a novel fabrication route for the mass production of electro-catalytic sensors for analytical and forensic applications.

Screen printed electrochemical platforms for pH sensing

We explore the possible use of screen printing technology for fabricating disposable electrochemical platforms for the sensing of pH. These screen printed pH sensors incorporate the pH sensitive phenanthraquinone moiety which undergoes a Nernstian potential shift with pH, and the pH insensitive dimethylferrocene which acts as an internal reference. This generic approach offers a calibration-less and reproducible approach for portable pH measurements with the possibility of miniaturisation allowing incorporation into existing sensing devices. The advantages, limitations and future prospects of this fabrication approach for producing electrochemical platforms for pH sensing are also discussed.

Nickel oxide screen printed electrodes for the sensing of hydroxide ions in aqueous solutions

Nickel oxide bulk modified screen printed electrodes are developed for the first time and explored towards the electroanalytical sensing of hydroxide ions and shown to be analytically useful. The nickel oxide screen printed sensor allows the detection of hydroxide ions over the low micro-molar to milli-molar range with a detection limit of 23 µM. The sensor is simplified over existing analytical methodologies and given its disposable and economical nature holds promise for the sensing of hydroxide ions and consequently the measurement of pH in aqueous solutions.