[A method for determining urea by using immobilized urease]

An available method was developed for manual measurements of urea in biological fluids with the use of urease immobilized in sepharose gel. The suggested technique is more reagent-saving (the same reagent may be used for up to 500 times), 3-6-fold more rapid, and twice more sensitive than the routine phenolhypochlorite method with soluble urease. The method is characterized by a high analytical reliability, its results are in high correlation with the soluble urease procedure and with the diacetylmonoxime method (r = 07988 and 0.995, respectively). It is particularly fit for rapid analysis of the urea and convenient for small laboratories.