A Multichannel Automated Amperometric Test System for Glucose Monitoring Biosensor Quality Control Testing
✍ Scribed by Qiang Chen; Brian Kersten; Jay Li; Christine Wu; Priya Jagasia; Al Ewing
- Publisher
- John Wiley and Sons
- Year
- 2001
- Tongue
- English
- Weight
- 135 KB
- Volume
- 13
- Category
- Article
- ISSN
- 1040-0397
No coin nor oath required. For personal study only.
✦ Synopsis
An automated system has been designed for routine amperometric testing of biosensor components for Cygnus Inc.'s GlucoWatch glucose monitoring device. Sensitivity of biosensors is measured as the amperometric response to hydrogen peroxide standards, across development lots, for lot release, and for stability testing. The automated system consists of ®ve principal components: 1) a Gilson Model 223 liquid handling system with Model 402 syringe pump; 2) ¯ow cells designed to hold biosensors; 3) programmable calibrated potentiostats; 4) valves, solenoids, and relays to direct ¯ow and initiate potentiostats; and 5) software to control the liquid handling and potentiostat programming, and software for data acquisition. The system sequence consists of downloading potentiostat voltage-time programs, preconditioning the sensors under test, and then directing 0, 1, 5, and 10 mM H 2 O 2 to the biosensors. The potentiostat is started after each injection, and the resulting current is measured at selected intervals. Sensor current is measured over 5 minutes, and the sensor response is determined using the observed current at selected intervals. Sensor sensitivity is measured as the slope of sensor response versus H 2 O 2 concentration. The limit of quantitation of this automated method is 0.5 mM H 2 O 2 and the analytical precision is less than 10 % RSD at 5 mM H 2 O 2 . Peroxide decline in standards is limited to less than 5 % over 8 h at room temperature, and less than 2 % over the typical analysis time of 4 h. This system provides a reliable, precise and easy procedure for multichannel amperometric biosensor testing.