Instructions for use

 

Intended use:

          This device is based on the antibody capture immunochromatography technique for the simultaneous detection of IgM and IgG directed against the new virus SARS-CoV-2 (COVID-19 ) in serum, plasma or whole blood. In order to meet the growing demand for rapid and reliable detection solutions for SARS-CoV-2 coronavirus infection, Spartacus-Biomed presents its IgM/IgG antibody test kit as a diagnostic aid. This lateral flow device can reliably detect antibodies to the new SARS-CoV-2 virus in 10 minutes.

 

Principle:

          The 2019 coronavirus epidemic (SARS-CoV-2) has been declared a public health emergency by the World Health Organization and is evolving into a pandemic associated with significant morbidity and mortality. SARS-CoV-2 is genetically linked to SARS-CoV. The SARS-CoV-2 coronavirus belongs to the genus Nestovirus, Coronaviridae. Three genera have been studied: α, β and γ. The genera α and β are pathogenic for humans. This virus is transmitted by direct contact with secretions, by aerosols or droplets.

The principle of LFA COVID-19 IgG & IgM Rapid Test Device is an antibody capture immunochromatography for the simultaneous detection of IgM and IgG antibodies against the SARS-CoV-2 virus in serum, plasma or blood samples. When the sample is deposited in the well of the cassette (see the diagram below), it moves by capillarity along the membrane. If the sample contains an anti-SARS-CoV-2 antibody (IgG and/or IgM), the antibody will bind to the new gold-labeled virus antigen.

Specific antigens (recombinant envelope proteins) to the SARS-CoV-2 virus are conjugated to colloidal gold. Anti- IgM and anti-IgG antibodies are immobilized on two test lines (see diagram), forming two visible pink lines and then indicating positive results. If anti-SARS-CoV-2 antibodies are absent in the sample, these pink lines will not appear indicating a negative result.

After the test is completed, the control line should always appear in the control area (C). The absence of the pink control line C indicates an invalid result (see the diagram below).

The LFA COVID-19 IgG & IgM Rapid Test Device test was compared to a standard commercial RT-PCR test using 100 clinical samples. The results show that the device has a specificity of 100% for IgG and for IgM and a sensitivity of 96% for IgG, 92% for IgM and 94% for combined IgG and IgM.

Performances, sensitivity and spécificity:

The LFA COVID-19 IgG & IgM Rapid Test Device test was compared to a standard commercial RT-PCR test using 100 clinical samples. The results show that the device has a specificity of 100% for IgG and for IgM and a sensitivity of 96% for IgG, 92% for IgM and 94% for combined IgG and IgM.

 

Reactivity and cross-reactions: 

No cross-reactivity was detected for human blood samples positive for Syphilis or for infectious viruses such as influenza A or B, RSV, adenovirus, hepatitis B and C or HIV). The following molecules have been tested and have no interference: Triglycerides (100mg / dL), Ascorbic acid (20mg / dL), Hemoglobin (1000mg / dL), Bilirubin (100mg / dL) or Cholesterol (6mmol / L).

 

Storage and stability:

1. The Kit must be stored between 4 ℃ and 30 ℃, dry and protected from light. The cassette should be used immediately after opening the pouch which is a protection from moisture.

2. The test is stable until the expiration date printed on the package. The cassette must remain in the sealed and closed pouch until use.

3. Only clear, non-hemolyzed samples are recommended for this test. Icteric or lipemic sera may also cause erroneous results.

3. Whole blood collected at the fingertip should be tested immediately to avoid clotting.

4. Tubes containing anticoagulants such as EDTA, citrate or heparin should be used for the storage of whole blood.

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Manual

Procedure and Interprétation of results::

- Whole blood samples can be taken by finger prick or venipuncture, following the establishment's routine procedures.

Whole blood on fingers:

1- Clean the finger area to be pricked with an alcohol swab. Let it dry.

2- Without touching the puncture site, rub your hand towards the middle or ring finger.

3- Pierce the skin with a sterile pricking pen and wipe the first drop of blood.

4- Gently rub the hand of the wrist with the pricked finger to form the drops of blood on the puncture site.

5- Collect 2 drops (avoid air bubbles) of blood using the pipette provided (20 µL), then place in the well of the cassette, immediately add 1 drop of buffer and start the timer for 10 min.

6- Whole finger blood should be tested immediately after collection.

Venous whole blood:

1- Collect whole venous blood in a tube containing an anticoagulant.

2- For serum samples, take blood in a tube without anticoagulant and allow it to clot.

3- For plasma samples, draw blood from a tube containing an anticoagulant. Separate the plasma from the blood as soon as possible to avoid hemolysis. Use only clear, non-hemolyzed samples.

4- The blood can be stored between 2 and 8 ° C for up to three days if the tests cannot be carried out immediately. Allow the sample to reach room temperature before use.

5- Remove the test cassette from its sealed pouch and immediately use it on a level surface. Using the disposable pipette provided, take 10 µl of serum / plasma (one drop) or 2 drops of whole blood (20 µL) then place in the well of the cassette, immediately add 1 drop of buffer and start the Timer for 10 min.

 

Results and recommendations:

1- Wait until the colored line(s) appear. Read the results at 10 minutes. Do not interpret the result after 20 minutes.

2- For professional use in in vitro diagnostics.

3- Do not use the test if the pouch containing the cassette is damaged.

4- Do not use after the expiry date indicated on the packaging. Do not reuse.

5- Do not mix different samples.

6- This test must be carried out between 15 and 30 ° C. If the blood, plasma or serum samples are kept in the refrigerator, make sure that all the test components are brought to room temperature before performing the tests .

7- Wear protective clothing such as lab coats, disposable gloves and eye protection. Handle all samples as if they contain infectious agents. Observe the precautions established against microbiological risks throughout the test procedures.

8- Throw away any material used in a bin suitable for biological risks. Handling and disposal of hazardous materials must comply with local regulations.

9- Wash your hands thoroughly after completing the tests.

10- Do not eat, drink or smoke in the area where the samples or kits are handled.

11- Keep out of reach of children.

 

Important notes:

The color intensity of the IgG and / or IgM test lines will vary depending on the concentration of anti SARS-CoV-2 antibodies in the sample. Therefore, any shade of color in the region (s) of the IgG and / or IgM test line should be considered positive.

An internal control is included in the test. Line C represents the internal positive control. It confirms that the volume of sample deposited in the well of the cassette is sufficient and that the technical procedure has been carried out correctly. The absence of the pink control line (C) indicates an invalid result. Good laboratory practice, however, recommends the daily use of an appropriate external positive control.