The Wondfo Test Cassette is a rapid chromatographic immunoassay for the qualitative detection of hepatitis B surface antigen (HBsAg) in human whole blood, serum or plasma.
Use for in vitro diagnostic use only and by healthcare professionals only.
Hepatitis caused by virus B (HBV) is one of the main infectious diseases that can be transmitted by blood transfusion, and the majority of the human population is now a carrier of this virus.
HBV, a member of the hepadnavirus family, belongs to the DNA viruses. Its core contains double-stranded circular DNA and DNA polymerase. The superapse contains lipoprotein. The main serological sign of HBV infection is the presence of five signaling proteins. These proteins are: HBV surface antigen (HBsAg), HBsAg antibodies (HBsAb), HBV envelope antigen (HBeAg), HBeAg antibodies (HBeAb), and HBV core antigen antibodies (HBcAb). In the test system under consideration, the HBV surface antigen (HBsAg) was used.
PRINCIPLE OF OPERATION
When a sample is added to the cassette, it is absorbed by capillary action, mixes with the antibody conjugate, and passes through a membrane previously coated with a thin film of such conjugate.
When antigen levels equal or exceed the detection threshold of the test, the sample's HBsAg is combined with the antibody conjugate in the "cushion" and then fixed with the antibody immobilized in the test zone (T) of the device. This results in a visible colored band in the T-zone, indicating a positive result.
If antigen levels are zero or below the detection threshold of the test, no color band appears in the test T zone, indicating a negative result.
If the testing procedure is carried out correctly, a colored line will appear in the control zone (C).
PRECAUTIONARY MEASURES
1. This test kit is for in vitro use only. Do not swallow.
2. All specimens should be considered as potential vector-borne disease agents.
3. Blood samples taken from patients with jaundice, with lipemia; hemolyzed, heat-treated, or contaminated blood samples may give erroneous results.
4. After the first use, the test system is discarded. It can only be used once.
5. Do not use the test kit after the expiration date.
6. Do not use the test kit if the soft pack is damaged or poorly sealed.
7. Keep out of the reach of children.
8. DISPOSAL OF THE DIAGNOSTIC TEST: The used device is infectious. The disposal process of the used test system should be carried out in accordance with local laws or laboratory regulations.
STORAGE AND STABILITY
1. Store at 2°C ~ 30°C in sealed soft packaging until the expiration date.
2. Keep away from direct sunlight, moisture and heat.
3. DO NOT FREEZE.
SPECIMEN COLLECTION AND PREPARATION
1. Collect whole blood with an appropriate anticoagulant. Use all blood immediately or separate serum or plasma from blood cells as soon as possible to avoid hemolysis. Only clear, non-hemolyzed specimens may be used for testing.
2. Testing should be done immediately after sample collection. Do not leave samples at room temperature for long periods of time. Samples can be stored at 2○C ~ 8○C for 3 days. For longer storage, specimens should be stored below -20°C.
Whole blood samples that have been stored at 2°C -8°C for more than 7 days should not be tested.
3. Before testing, samples should take room temperature (10°C ~30°C). Frozen specimens should be completely thawed and mixed thoroughly before the procedure. Samples should not be repeatedly frozen and thawed.
TEST PROCEDURE
The test kit and sample must be at room temperature (10°C ~30°C) before testing.
1. Remove the test cassette from the soft packaging by tearing it at the notch and place it on a flat surface.
2. To test whole blood: a) Holding the sample pipette upright, add two drops of whole blood (approximately 50 µl) to the sample well (up to the mark line). b) Add two drops (approximately 50 µl) of diluent buffer directly from the bottle to the sample well.
For serum/plasma testing: Holding the sample pipette upright, add four drops (approximately 50 µl) of serum or plasma to the sample well.
3. Leave for 15 minutes, then fix the results. Do not read results after 30 minutes.
INTERPRETATION OF THE RESULTS
Positive (+)
Pale pink streaks are visible in both the control zone and the sample application zone. A positive result indicates that the HBsAg concentration is equal to or greater than the detection threshold of the test system.
Negative (-)
A pale pink band is visible in the control zone. No color band appears in the sample application area. A negative result indicates a zero HBsAg level, or that the HBsAg concentration is less than the sensitivity threshold of the test system.
Invalid
There are no visible bands, or there is such a band only in the sample application zone, but not in the control zone. Repeat the procedure with a new test kit. If the test fails, please contact the distributor or store where you purchased the product with the serial number.
Note: Color intensity or line width does not matter.
LIMITATIONS OF THE TEST PROCEDURE
1. This test is only designed to test whole blood, serum or plasma samples. There is no evidence that this test system will work with other samples.
2. This test is a qualitative immunological screening procedure. It is not designed to quantify HBsAg concentration.
