Abstract
This paper describes the performance of suppressed ion chromatography coupled with a Nafion membrane tube-based on-line concentration technique for the determination of urinary orotic acid, which serves as a biochemical indicator for ornithine transcarbamylase deficiency. After the separation of the analyte by the chromatography, it is concentrated while the eluent flows through the Nafion membrane tube, meanwhile, a nitrogen gas flows outside the tube to remove the solvent. The peak of orotic acid was increased with increasing sample residence time, nitrogen gas flow rate, and concentration temperature. With the concentrator, the detection sensibility was improved, and the lower detection limit was obtained compared to that without the concentrator. The optimized system has successfully been applied to the determination of orotic acid in real urinary samples.
