sample is serum or plasma.

Procedure :
1.prepare two test tubes mark one as test tube and the other is standard tube .

2.in standard tube put : 1 ml buffer + one drop urease (R2) + 10 µ standard reagent (R1) leave for 5 min. in room temp.

3.in test tube put at same time : 1 ml buffer + one drop urease (R2) + 10 µ serum or plasma then leave for 5 min in room temp.

4.then put 200 µ of Reagent 4 (R4) and leave for 5 min. in water bath or 10 min. in room temp.

5.Measure at 580 wave length.

Calculation :
[ reading test / reading standard ] x 50 =.......mg / dl . OR [ reading test / reading standard ] x 8.33 =......mmol /l

Normal values:
15 - 45 mg / dl.
OR
2.5 - 7.5 mmol / l.