Simple and sensitive determination of urea in serum and urine.

Abstract:

:In this method for serum and urinary urea determination, the same reagent is used without predilution of urine samples. The method is based on the pH increase resulting from the ammonia released by urease hydrolysis of urea. o-Cresolphthalein complexone is used to monitor the pH change colorimetrically. Urea concentration and absorbance at 570 nm are linearly related for concentrations as great as 600 mmol/L for urine samples and 100 mmol/L for serum. There are no clinically significant interferences from physiological substances or drugs, and precision and accuracy are excellent (CV approximately 2%, except at very low concentrations in serum; analytical recovery was 99% in urine, 100% in serum). Results by this method (y) and by the Astra method (x) for urine correlated well (y = 0.991x - 2.87, Sy/x = 9.21, r = 0.994), as did the results by this method and by the total enzymatic method (x') for serum (y = 1.002x' + 0.192, Sy/x' = 0.598, r = 0.997). This method is applicable to automated as well as manual instruments, and one-reagent or two-reagent formats can be used.

journal_name

Clin Chem

journal_title

Clinical chemistry

authors

Orsonneau JL,Massoubre C,Cabanes M,Lustenberger P

subject

Has Abstract

pub_date

1992-05-01 00:00:00

pages

619-23

issue

5

eissn

0009-9147

issn

1530-8561

journal_volume

38

pub_type

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