The Determination of Urea in Urine
نویسنده
چکیده
The method outlined in the foregoing. paper for the estimation of urea in blood is perfectly reliable for larger quantities of urea (up to 25 mgms. or perhaps more). Its adaptation to the determination of urea in urine using only a small amount of the urine is shown in this paper. The method to be described is slightly more accurate than the rapid clinical method proposed earlier.’ The reason for this is twofold; the rapid titration method gives results slightly lower than the theoretical on account of the presence of carbon dioxide during the titration, and titrations pcrformed in a mixture such as urine are not as accurate as in the case of the neutralization of a pure solution of an acid by an alkali. Two l-cc. portions of the urine are measured into test tubes by means of an Ostwald pipette.2 The urine is now diluted to about 10 cc., 1 cc. of the soy bean extract added to one tube and from 0.5-l cc. of toluene to each. The tubes are allowed to remain at room temperature over night. With the following exceptions, the remainder of the procedure is exactly similar to that described in the foregoing article on the determination of the urea in blood. No alcohol need be added to the contents of the cylinders, for oil alone suffices to prevent excessive frothing. The first absorption flask attached to the cylinder containing the urine and the ferment extract is charged with 50 cc. of & hydrochloric acid instead of 25 cc. In the case of pathological urines
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تاریخ انتشار 2003