296 Antcncr, Vuataz, Bruschi and Kaeser: Determination of citric acid

A method is described for the determination of citric acid in the routine clinical investigation of urine and serum. It is based on a combination of the methods of GEY, LANE and CHEN. The method has been used for several years and has been completed by a statistical analysis. Es wird die Beschreibung einer Zitronensäurebestimmungsmethode im Harn und Serum, die sich gut zu Reihen-untersuchungen in der Klinik eignet, gegeben. Sie beruht auf der Kombination der Methoden vonGEY und LANE und CHEN. Während mehrerer Jahre wurde diese Methode angewendet und durch eine Statistik ergänzt. Recent progress in clinical chemical methods has shown the importance of citric acid in the different metabolic pathways. Its storage and release is influenced by vitamin D and parathormone, and it is a metabolite of the Krebs cycle. Citric acid is also a bone component. Moreover, the secretion and tubular reabsorption of renal citric acid are two problems which remain unsolved. Determina-tions of serum and urinary citric acid are thus not only of interest in the different bone diseases, but also in certai