GAS-DRIVEN HIGH-SPEED ROTATING DISc ELECTRODE - Isis Project No 2208
The Technology
An improved design of high speed rotating disk electrode, that uses high-pressure gas instead of a mechanical drive, delivering order-of-magnitude improvements in sensitivity.
The sensitivity of electrochemical sensors can be dramatically improved by quickly passing the liquid being examined over the sensor surface. This can be achieved by mounting the sensitive electrode surface on a rotating disk, or by using channels, jets, or tubes to accelerate the liquid flow across the surface. Rotating disk electrodes are particularly attractive because they are simple to use.
When a disk rotates at high speed the fluid near the surface adopts a laminar flow – flowing like sheets over itself, not turbulently as might be expected. This greatly increases the amount of sample fluid exposed to the electrode surface; quickly removing spent chemicals allowing “fresh” materials to be brought into contact with the sensing surface.
However the usefulness of rotating disk electrodes is limited because the mechanical drive mechanisms used only reach certain speeds, and also the electrical motors needed interfere with the sensitive electrochemical measurements. Recently insonation (targeted ultrasound) and microwave radiation have been successfully used to promote the movement of fluids across the surface of solid electrodes – these methods increase sensitivity but are complex and expensive.
The Oxford Invention
The Oxford invention is a new design of rotating disk electrode, which moves beyond the status quo of mechanical devices, by using high-pressure air to turn a miniature turbine and provide rotation. This technology is well known to anyone who has experienced a dentist’s drill, but its application in electrochemistry has produced some dramatic results.
The Oxford design of enhanced rotating disk electrode has been tested for the detection of Arsenic (III) using a gold electrode, and shown to increase detection sensitivity by an order of magnitude when compared to non-rotating electrodes.
Commercial Opportunity and Patent Status
This work is the subject of a patent application, and Isis would like to talk to companies able to develop this technology further. Please contact the Isis Project Manager to discuss this opportunity.
Other Sensor Projects
1529 - pH Sensor Electrodes
2350 & 2401 - Sensitive Gas Sensors
2618 - Real World Arsenic Detection
2698 - Cryo-Electrochemical ESR Cell
Request Further Information: Project Number 2208 - Gas Driven High Speed Rotating Disc Electrode