Home/How CGMs Work/Enzymatic Chemistry: GOx vs. GDH
Back to How CGMs Work

Enzymatic Chemistry: GOx vs. GDH

Two key enzymes power CGM sensors: Glucose Oxidase (GOx) offers superior specificity while Glucose Dehydrogenase (GDH) provides different performance characteristics.

Enzymatic Chemistry: GOx vs. GDH

The Core of Glucose Detection

Enzymatic chemistry drives continuous glucose monitors. Two key enzymes are at play.

Glucose Oxidase (GOx)

How It Works

GOx catalyzes glucose, producing gluconic acid and hydrogen peroxide. Electrodes measure the hydrogen peroxide to calculate glucose levels.

Key Advantage

GOx targets glucose only—excellent specificity.

Glucose Dehydrogenase (GDH)

How It Works

GDH catalyzes glucose, producing an electron transfer that is directly measured to indicate glucose levels.

Key Consideration

GDH is less specific and may be affected by other substances.

Comparison

| Feature | GOx | GDH | |---------|-----|-----| | Specificity | High | Moderate | | Interference resistance | Good | Variable | | Sensor longevity | Longer | May need more calibration | | Oxygen dependency | Yes (traditional) | No |

Choosing Between Them

Modern sensor design often favors GOx with mediator chemistry (wired enzyme), combining the specificity of GOx with reduced oxygen dependency.