Evaluation of the Technicon Bound Uricase Method for the Determination of Uric Acid in Urine

Abstract

We have evaluated the Technicon bound uricase method for the determination of uric acid in urine with the AutoAnalyzer IL The general analytical characteristics of the method, and the effect of urine on the immobilized uricase nylon tube reactor were investigated.The method was found to be linear up to 7.0 mmol/1 with aqueous Standards and up to 5.0 mmol/1 with urine samples.Between-days imprecision had a coefficient of Variation (CV) of 1.6% for values of about l .2 mmol/1, and 0.8% for values above 3.5 mmol/1. Within-run imprecision gave a CV of 0.7% for values of 1.07 and 2.95 mmol/1 and a CV of 0.4% for a value of 4.77 mmol/1. The mean analytic recovery was 99.1% (ränge 93.8-103.0%). The sample interaction was 0.9%.The correlation with the phosphotungstate method and the manual Dutch Standard method was good, but the enzymatic values were 20% lower than the phosphotungstate values. Storing the immobilized uricase nylon tube reactor at 4 °C, when not in use, prolonged the lifetime by neafly 50%. Urine samples were not different from aqueous uric acid Standards in their effect on the stability of the uricase nylon tube reactor. Evaluation des Technicon^Verfahrens mit immobilisierter Uricase zur Harnsäurebestimmung im HarnZusammenfassung: Das Technicon-Verfahren mit immobilisierter Uricase zur Harnsäurebestimmung im Harn mit dem AutoAnalyzer II wurde geprüft. Die allgemeinen analytischen Charakteristika der Methode und die Wirkung von Harn auf die an Nylon-Schlauch inimobilisierte Uricase wurden untersucht.