CLINICAL SIGNIFICANCE
Decreased levels are associated with malnutrition and hypoalbumlnaemla. Increased levels are observed in dehydration and hyper-globulinaemia.
PRINCIPLE
In the presence of alkaline cupric sulphate, the proteins produce a VIOLET colour. Intensity of the colour is proportional to protein concentration.
REAGENTS SUPPLIED
| Cat.No.A190 |
Composition |
| 1. Biuret Reagent |
100mL |
| Cupric sulphate |
6mMols/L |
| Sodium and Potassium tartarate |
21mMols/L |
| Sodium Hydroxide |
750mMols/L |
| Potassium lodide |
6 mMols/L |
| 3.Standard (Albumin) |
2.5 mL |
| Value of Albumin Standard |
8.0Gms/dL |
Preparation of Working Reagent
All reagents are ready to use.
STABILITY
Biuret (Reagent No. 1)
18 months at 18-25°C away from light. Protein Standard (Reagent No.3) 18 months at 2-8°C. Do not freeze the Standard.
SAMPLE
Serum or plasma which has no sign of haemolysis. Common anticoagulants have no interference on this assay. Avoid haemolysed serum or plasma. (All samples should be handled as potential infective agents as no laboratory methods make conclusive findings for its safety. Therefore, adequate protective laboratory measures should be taken while handling such materials).
SYSTEM PARAMETERS
| Reaction |
End Point |
| Temperature |
30° + 5°C |
| Wavelength |
550 + 20nM |
| Standard Concentration |
4.0 Gms/dL |
| Absorbance Range |
0-2°A |
| Cuvette Path Length |
1 cM |
| Reagnet Volume |
1000µL |
500µL |
| Sample Volume |
50µL |
20µL |
| Reaction Time 10 Mins at RT/5 Mins at37 C |
| Protein Standard Value |
8.0Gms/dL |
| Linearity |
15.0Gms/dL |
| Max. limit of blank rgt. |
0.4°A |
| Final Colour Stability |
30 Minutes |
|
MANUAL METHOD
1
| Pipette into 3 Test Tubes |
B
(ml) |
S
(ml) |
T
(ml) |
| Reagent No. 1 |
3.0 |
3.0 |
3.0 |
| Standard Reagent No 3 |
- |
0.1 |
- |
| Sample |
- |
- |
0.1 |
2.Mix well Incubate for 10 minutes at RT or 5 minutes at 37°C.
3.Read at 550 nM (550+20 nM) or GREEN filter against Blank.
4.The final colour is stable for approximately 30 minutes.
MICRO METHOD FOR DISCRETE ANALYSERS
Pipette into clean dry test tubes labeled as Blank (B), Standard (S), and Test (T)
| For Cuvette Volume |
1.0mL |
0.5mL |
| Reagent 1 |
1000µl |
500µl |
| Sample or Standard |
50µl |
20µl |
Mix well. Incubate at 37°C for 5 minutes or at RT for 10 minutes. Read at 550 nM (550+20 nM) against blank. The final colour is stable for apx. 30 mins.
NOTE : Progrmame the analyser using system parameters. A specific programme data sheet may be provided for each analyser upon request.
RESULTS
Compute O.D.Test
Total Proteins in Gms/dL= O.D.STD xC
*C = Concentration of Standard as printed on
label.
This kit contains two different standards for
Albumin and Proteins assays.
Reagent No. 3 Standard for Total Proteins only.
Reagent No. 4 Standard for Albumin only.
MAKE SURE THE STANDARD USED IS
APPROPRIATE BEFORE REPORTING THE
RESULTS.
EXPECTED VALUES
6.5to7.5Gms/dL
As with all diagnostic methods, the final diagnosis should not be made on the result of a single test as well as laboratory diagnosis must be confirmed with clinical manifestations
LINEARITY
Colour development gradually increases on prolongation of time more than 30 minutes specified in the procedure. This assay is linear up to 15. 0Gms/dL proteins. For values higher than 15.0 Gms/dL repeat the test with serum diluted in 0.9% sodium chloride solution. Multiply the results by the dilution factor applied i.e. multiply by 2 for a 1:1 dilution.
NOTE: This method is not useful for Microprotein/
C.S.F.Protein assay.
(For Microprotein assay, BIOLAB offers
C.S.F.ProteinKit-Turbidometry method).
QUALITY CONTROL
To ensure adequate quality control, each kit should be tested against a standard control sera. It should be realised that the use of quality control material checks both instrument and reagent function together. Factors which might affect the performance of this test include proper instrument function, temperature control, cleanliness of glasswares and accuracy of pippetting. It is appropriate to establish each laboratory's accuracy constant and interpretvalues accordingly.
WARNING
This reagent system is for in vitro use only. This reagent system is contains preservatives and components that have not established for safety if contacted on broken skin or eye or taken orally. In case of such incidents wash off with plenty of water, or consulta physician.
BIBLIOGRAPHY
GORNALL A.C., BARDAWILL C.J., DAVID M.M. -J.Biol.Chem., 1949,177,751. N. TIETZ, Fundamentals of Clin. Chem., W.B. Saunders Company, Philadelphia P.A.
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