Rapid CRP Serum/Whole Blood Cassette Test
INTRODUCTION
The Rapid CRP Serum/Whole Blood Cassette Test is a colloidal gold/antibody complex
based immunoassay designed for the semi-quantitative detection of human CRP in serum
or whole blood. It is intended for professional use as indicator of inflammatory processes.
Elevated levels of CRP are not specific to any one disease, but have been linked to a
number of diseases, including: bacterial infections, rheumatoid arthritis, myocardial
infarctions, and malignant tumors. Elevated levels of CRP are also a good indicator of
future cardiac problems.
During an inflammatory process the level of CRP rises dramatically. CRP concentration
can rise from a basal level of 1 to 5 g/ml to 500 g/ml within hours of inflammation
onset. Due to the large range over which CRP levels can vary, few semi-quantitative
rapid CRP tests are currently available.
PRINCIPLES OF THE PROCEDURE
The Rapid CRP Serum/Whole Blood Cassette Test consists of a chromatographic
absorbent device and a combination of polyclonal antibodies that selectively detect CRP
in serum or whole blood samples and give semi-quantitative results. In ten minutes,
levels of CRP in samples can be detected within the following ranges: <0.1 g/ml, 0.11.0 g/ml, 1.0-10 g/ml, and >10 g/ml.
Serum or whole blood migrates through the absorbent area and along the test membrane.
CRP present in the specimen is bound by antibody-dye conjugate forming antibodyantigen complex. The complex is captured by anti-CRP antibody immobilized in the
three test zones (test line 1, test line 2, and test line 3) of the membrane forming pink-rose
bands. The use of three test lines to yield semi-quantitative results is described further in
the Result Interpretation section below. In the absence of CRP no lines will form in the
three test zones. Dye conjugate is captured by the antibody immobilized in the control
zone (control line) of the membrane, again producing a pink-rose band. A band at the
control line shows that the test has worked correctly and results from the test lines should
be considered valid.
TEST STORAGE
Store the test below 28C, do not freeze. Prior to use bring test and components to room
temperature.
WARNINGS AND PRECAUTIONS FOR USERS
1. Handling should preclude any pipetting by mouth.
2. Do not allow smoking or eating where specimens and reagents are being handled.
3. Wear disposable gloves while handling kit reagents or specimens. Wash hands
thoroughly afterwards.
4. Avoid splashing or aerosol formation.
5. Clean up spills thoroughly using an appropriate intermediate-to-high level
disinfectant.
6. Decontaminate and dispose of all specimens and potentially contaminated materials as
if they were infectious.
7. Do not use reagents after the expiration date.
8 For in vitro diagnostic use only.
Specimen Collection and Preparation
Either whole blood, plasma or serum may be used as samples for this procedure. For the
whole blood or plasma procedure, collect blood in a tube containing 5mM EDTA or
10mM citrate as the anticoagulant. If serum samples are to be used, collect blood in a
tube without anticoagulant and allow to clot. Heat inactivation of samples may lead to
hemolysis or protein denaturation and therefore should be avoided.
MATERIALS PROVIDED
1. CRP Serum/Whole Blood cassettes
MATERIALS REQUIRED BUT NOT SUPPLIED
1. Disposable droppers
2. Automatic pipettors
3. Microfuge tubes (or other similar tubes).
ASSAY PROCEDURE
1. Bring all reagents and specimens to room temperature.
2. Dispense three drops of each standard and serum/whole blood samples into specimen
wells of cassettes (run at least two duplicates of each standard and sample).
3. Incubate 10 minutes for serum, or 15 minutes for whole blood samples
4. At the end of the test, read the test results by comparing samples to standards to
determine bracketed concentration of CRP in the sample.
RESULT INTERPRETATION
Sample Results for CRP test:
0g/mL
0.1g/mL
1g/mL
10g/mL
100g/mL
1. At 0.1 g/ml or less, a weak signal should appear at test line 1 (T1).
2. At 1.0 g/ml, a strong signal should appear at test line 1 (T1).
3. At 10 g/ml, strong lines should appear at both T1, accompanied by a medium
strength signal at test line 2 (T2).
4. At 100 g/ml, strong lines should appear at T1, accompanied by a medium
strength signal at test line 2 (T2) and a weak signal at test line 3 (T3).
5. If no control (C ) signal is observed, the test result should be considered invalid
and be run again.
APPENDIX 1
Diagramatic Presentation of CRP 3 Test Line Whole Blood Cassette Test To Reveal
Relative Signal Intensity As A Function of CRP Concentration (ug/ml) in Log Scale.
CRP- 3Test Line Whole Blood Cassette Test
Relative Intensity
3.5
3
2.5
2
Test Line 1
1.5
Test Line 2
1
Test Line 3
0.5
0
-2
-1
0
1
2
Log [CRP ug/ml]
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