Which detection methods are used for glucose oxidase–based measurements?

• A. Trinder reaction with colorimetric detection
• B. Polarography with oxygen consumption
• C. Trinder reaction and Polarography (both)
• D. Fluorometric detection

Answer: (C)

Glucose oxidase-based measurements rely on the enzyme consuming oxygen and producing hydrogen peroxide when glucose is present. Detection can occur in two main ways. One uses the Trinder colorimetric method: hydrogen peroxide generated by the reaction is converted by peroxidase with a chromogen to yield a colored signal that correlates with glucose concentration. The other uses electrochemical detection by monitoring the consumption of oxygen with a polarographic (or amperometric) sensor, where the signal reflects the amount of glucose via the rate of oxygen depletion. Both approaches are standard for glucose oxidase assays, so combining them captures the two widely used detection strategies. Fluorometric detection exists in some setups, but the classic glucose oxidase measurements emphasized here are colorimetric and electrochemical oxygen-detection methods.