A colorimetric method for the direct determination of urea in urine

The Direct Colorimetric Determination of Urea in Blood and Urine

Methods for the determination of urea in biological fluids have passed through an interesting cycle (cf. Peters and Van Slyke (3) pp. 539-544). The earliest procedures were strictly chemical ones, involving precipitation of the urea as an insoluble mercury complex or decomposition of the urea by means of heat or hypobromite. The use of the highly specific enzyme urease occurring in the jack and...

A Direct Colorimetric Method for the Determination of Urea in Blood and Urine

A sensitive method for the colorimetric determination of urea.

A method is described for the direct colorimetric determination of urea in biological fluids. The method depends on the reaction (first described by Wheatley, 1948) between urea, diacetylmonoxime, and phenylanthranilic acid in the presence of controlled amounts of oxidant; chloride ions are included to sensitize the reaction; manganous ions stabilize the resultant colour; and phosphate enables ...

Direct fluorometric determination of urea in urine.

Urea in biological fluids has been determined by a variety of direct and indirect procedures. Some indirect methods depend on the hydrolysis of urea with the enzyme urease to form ammonia, with subsequent quantitation of the ammonia by nesslerization (1-4). Undesirable features of these indirect methods are the use of relatively unstable reagents and loss of ammonia during the procedure. Direct...

A colorimetric method for the determination of methylamine in urine.

In the course of feeding experiments in which mono-, di-, and trimethylamines were fed to dogs, it was desirable to determine the urinary excretion of methylamine (monomethylamine). The available methods were found to be cumbersome and not well adapted to the routine analysis of a large number of urines. Weber and Wilson (1) separated ammonia from the amines by the use of yellow mercuric oxide ...