A simple method for the measurement of arginine in serum

A simple method for the direct measurement of arginine in 40 microL of serum is described. The technique is rapid (22 samples within 10 minutes), inexpensive (reagent cost: pounds 0.03 per test), accurate and relatively precise. The limit of detection is 1 mmol/L: it is therefore not suitable for normal basal arginine concentrations, but can be used when arginine concentrations are known to be raised.