Urea/BUN

Catalog Number: 04460715190

SYSTEM INFORMATION

For cobas c 311 analyzer:

INTENDED USE

In vitro test for the quantitative determination of urea/urea nitrogen in human serum, plasma and urine on Roche/Hitachi cobas c systems.

STORAGE AND STABILITY

UREAL
Shelf life at 2-8 °C: See expiration date on cobas c pack label.
On-board in use and refrigerated on the analyzer: 8 weeks
Diluent NaCl 9 %
Shelf life at 2-8 °C: See expiration date on cobas c pack label.
On-board in use and refrigerated on the analyzer: 12 weeks

Specimen collection and preparation

APPLICATION FOR SERUM AND PLASMA

cobas c 311 test definition
Assay type Rate A
Reaction time / Assay points 10 / 10-19 (STAT 4 / 10-19)
Wavelength (sub/main) 700/340 nm
Reaction direction Decrease
Units mmol/L (mg/dL, g/L)
Reagent pipetting Diluent (H2O)
R1 10 µL 90 µL
R2 38 µL 110 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 6 µL 15 µL 120 µL
Increased 2 µL

 

CALIBRATION

Traceability: This method has been standardized against SRMa) 912.

Calibrators S1: H2OS2: C.f.a.s.
Calibration mode Linear
Calibration frequency 2-point calibration
• after 4 weeks on board
• after reagent lot change
• as required following quality control procedures

CALIBRATION MODE

CALIBRATION FREQUENCY

2-POINT CALIBRATION

LIMITS AND RANGES

Measuring range

MEASURING RANGE

Serum/plasma

LOWER LIMITS OF MEASUREMENT

Lower detection limit of the test

SPECIFIC PERFORMANCE DATA

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

PRECISION

Precision was determined using human samples and controls in an internal protocol with repeatability (n = 21) and intermediate precision (serum/plasma: 3 aliquots per run, 1 run per day, 21 days;

INTERMEDIATE PRECISION

INTERMEDIATE PRECISION

METHOD COMPARISON

Urea values for human serum, plasma and urine samples obtained on a Roche/Hitachi cobas c 501 analyzer (y) were compared with those determined using the corresponding reagent on a Roche/Hitachi 917/MODULAR P analyzer (x).

BABLOK W, PASSING H, BENDER R, ET AL. A GENERAL REGRESSION PROCEDURE FOR METHOD TRANSFORMATION. APPLICATION OF LINEAR REGRESSION PROCEDURES FOR METHOD COMPARISON STUDIES IN CLINICAL CHEMISTRY, PART III. J CLIN CHEM CLIN BIOCHEM 1988 NOV;26(11):783-790.