Determination of urea by ion chromatography with an immobilized urease reactor

Abstract An immobilized urease reactor can be used with ion chromatography for the simultaneous determination of urea, and sodium, potassium and ammonium ions. The conversion of urea to ammonium ion was found to be 76.5%. The calibration graph for urea was linear over the range 1 × 10 −5 −1 × 10 −3 M (RSD 3%). The method was applied to human urine and a chemical fertilizer.