Determination of ammonium in pediatric compound aminoacid injection by Ion Chromatograpy

OBJECTIVE To use ion chromatography method to optimize the assay of ammonium in pediatric compound aminoacid injection. METHODS The IC method was performed on a cation exchange column RFICTM IonPac® CG16 (4 mm×50 mm), CS16(4 mm×250 mm) by gradient elution at a flow rate of 1.0 mL·min^-1. The mobile phase A was 20 mmol·L^-1 methanesulfonic acid, the mobile phase B was 100 mmol·L^-1 methanesulfonic acid. The detector was conductivity detector with a suppressor(CERS 300, 4 mm) and the injection volume was 25 μl. RESULTS The linear range of the ammonium was 0.149 9-5.997 9 μg·mL^-1(r=0.998 4). The average recovery of it was 96.8% and the RSD was 2.82%. CONCLUSION The method was specific, accurate and suitable for the assay of ammonium for quantitative control of pediatric compound aminoacid injection.