Abstract
The difference between the solubility of monosodium urate (Na-urate) and uric acid in urine was investigated using concentrated urine as a solvent.
The solubility of uric acid increased with increasing pH and resembled a logarithmic function. On the other hand, the solubility of Na-urate as a function of pH was maximal at pH 5.6 and gradually decreased with increasing pH.
These results imply that urate has a remarkable tendency to remain in a supersaturated state. However if this is disturbed, crystallization may occur and exert pathogenic effects on the body even in the case of alkaline urine. These results also provide valuable data concerning urinary management in the treatment of hyperuricosuria.
