Principle
Urea is hydrolyzed to ammonia and carbon dioxide by urease. Ammonia produced reacts with @-ketoglutarate to form glutamate in presence of glutamate dehydrogenase. NADH is oxidized to NAD* in this reaction, which Is measured as a decrease in absorbance at 340 nm. The rate of decrease in absorbance at 340 nm. is directly proportional to BUN concentration in the specimen. The BUN concentration in the specimen is determined by comparing the sample reaction rafe to that obtained with a BUN standard
Procedure
Reaction type ….. UV – Kinetic
Reaction direction ………………….. Down
Wavelength …………….. 340 nm.
Flow Cell temperature ………… 25°C/30°C
Zero setting with ……………. Distilled water
Delay time……………… 30 seconds
No. of readings ………….2
Interval ………….. 30 seconds
Blank absorbance limit … ………. 2 1.000 Abs.
Sample volume ……. 0.01 ml (10 ul)
Reagent volume ……………………………………………… 1.0 ml
Factor …… ..20 (4 Abs. of std.)
Linearity………… 250 mg%
Quality Control
To ensure adequate quality control, it is recommended that each batch should include a normal and an abnormal commercial reference control serum. It should be realized that the use of quality control material checks both instrument and reagent functions together. Factors which might affect include proper instrument function, temperature, the performance of this test control cleanliness of glassware and accuracy of pipetting.
Other Details
The reagent kit should be stored at 2- 8 C and is stable till the expiry date indicated on the label. The working solution is stable for 45 days at 2- 8°C.
Krishnakant Kulkarni –
I’m the Accurex customer last 4 year, using Reagent and Semi Automated machine, good quality