UREA
UREA (NED METHOD):- The reagent set is intended for in vitro Quantitative determination of Urea in Serum and plasma. CLINICAL SIGNIFICANCE:Urea is the end product of the protein metabolism. It is synthesized in the liver from ammonia produced by the deamination of amino acids. It is transported by blood to the kidneys where it is excreted. Increased values are found in renal failure, urinary tract obstruction, shock, congestive heart failure and burns. Decreased levels are found in liver failure and pregnancy. PRINCIPLE:Urea forms with orthoβphthalaldehyde and Naphthylethylenediamine in the acidic medium a coloured complex. The value of colour formed is directly proportional to the urea concentration in the test sample and is measured by a fixed time method at 550 nm. REACTION:Urea + ODA β NHβ + HβONHβ + NED β Orange Color Complex. CONTENTS:Reagent 1 : ODA ReagentReagent 2 : NED ReagentReagent 3 : Urea Standard, 50 mg/dl MATERIALS REQUIRED BUT NOT PROVIDED: Clean Dry Glassware Laboratory Glass Pipettes or Micropipettes & Tips BioβChemistry Analyse SAMPLES: Serum, Heparinized/EDTA Plasma. Urea is reported to be stable in the serum for 5 days when stored at 2β8Β°C. PREPARATION OF REAGENT & STABILITY:All the reagents are ready for use and stable till the expiry date mentioned on the label when stored at 2β8Β°C. GENERAL SYSTEM PARAMETERS:Reaction type: End pointWavelength: 550 nm (520β550 nm) (Increasing)Temperature: 37Β°CReagent Volume: 1.0 mlSample Volume: 10 Β΅lZero setting: Against Reagent BlankLight path: 1 cm. PROCEDURE:Pipette into clean dry test tubes labeled as Standard (S) and Test (T) Addition sequence (S) (T) ODA Reagent 1.0 ml 1.0 ml Sample β 10 Β΅l Standard 10 Β΅l β Mix well and incubate at 37Β°C for 5 minutes NED Reagent 0.05 ml 0.05 ml Mix well and read the absorbance Aβ of the standard and test after exactly 5 minutes. Read Aβ after exactly 10 minutes. The absorbance reading to be recorded at 550 nm.Finally, take the difference AββAβ for both the standard and test. For Standard: ΞA = AβS β AβSFor Test: ΞA = AβT β AβT CALCULATION:Urea Concentration (mg/dl) =(ΞAT / ΞAS) Γ 50 NORMAL VALUE:Serum/plasma: 15β40 mg/dlEach laboratory should establish its own normal range depending on the population. LINEARITY:The method is linear upto 200 mg/dl. The value exceeding 200 mg/dl should be diluted appropriately with distilled water and the values obtained multiplied by dilution factor. QUALITY CONTROL:For accuracy it is necessary to run known controls with every assay. LIMITATION & PRECAUTIONS: Storage condition of the reagent and kit should be strictly followed. Avoid contamination of reagents. All glassware must be dry and free from detergent or debris. BIBLIOGRAPHY: Goodwin, J., Hart, T., Am. J. Chem., 26 (1977) 707 CODE NO. PACK SIZE Reagent 1 Reagent 2 Reagent 3 Z18 100 ml 1 x 100 ml 1 x 50 ml 1 x 3.0 ml BEACON DIAGNOSTICS PVT. LTD.424, NEW GIDC, KABILPORE, NAVSARI β 396 424, INDIA









