Neutralizing Antibody Test Instructions
Antigen Test Instructions
Please note that test kits can only be ordered by medical professionals or businesses and are required to be administered by a healthcare professional, a company nurse or by occupational health staff. We offer services to administer tests if required. Business orders require a Valid VAT number.
All instructions and data are for the aforementioned.
Test kits can be sold to the public if ordered with our GP visiting test service. Click here for details.
INTENDED USE
QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test is an immunochromatography based one step
in vitro test. The test is intended for professional and laboratory use as an aid in semi-quantitatively
monitoring human SARS-CoV-2 neutralizing antibodies in human fingerstick blood and serum
specimens after vaccination.
SUMMARY AND EXPLANATION
SARS-CoV-2 virus infects human cells through its binding to human ACE-2 receptor by its Receptor
Binding Domain (RBD) in Spike Protein (S Protein). Human antibodies against RBD either raised by
natural immunization through virus contact or by vaccination can block the binding of the virus to human
cell to prevent the infection. This type of antibodies is called SARS-CoV-2 Neutralizing Antibody. By
monitoring the level of SARS-CoV-2 Neutralizing Antibody, it provides the information of the efficacy of
vaccination.
QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test is a rapid immunochromatographic assay that
utilizes recombinant SARS-CoV-2 S1/RBD protein as the conjugate detector and mouse anti-human
IgG for membrane capture to detect SARS-CoV-2 neutralizing antibodies. When specimen is added to
sample port of the device, a colored band will be visible at the test line zone if SARS-CoV-2 neutralizing
antibodies are present. The color intensity is dependent on the concentration of SARS-CoV-2
neutralizing antibodies in the sample. On the other hand, a light color band will always appear at the
reference line zone. This reference band serves as a reference of set antibody titer in the sample. In
addition to the test line and reference line, there is a clear color band will always appear on the control
line zone to indicate that the test has been correctly performed and the test device functions properly.
PRECAUTIONS
Read the package insert carefully prior to testing the kit and follow the instructions to obtain accurate results.
1. For in vitro diagnostic use.
2. Do not use the kit contents beyond the expiration date printed on the outside of the box.
3. Do not interchange or mix different lots of components.
4. Disregard test results beyond the specified time (15 minutes).
5. Use appropriate precautions in the collection, handling, storage, and disposal of patient samples
and used kit contents.
6. Use of protective tools are recommended when handling patient samples.
7. Dispose of containers and used contents in accordance with Federal, State and Local requirements.
8. Do not reuse kit components.
9. The test device must remain sealed in the protective foil pouch until use.
10. Inadequate or inappropriate specimen collection, storage, and transport may yield inaccurate test
results.
11. Seek specific training or guidance if you are not experienced with specimen collection and handling
procedures.
12. If infection with a novel SARS-CoV-2 virus is suspected based on current clinical and
epidemiological screening criteria recommended by public health authorities, specimens should be
collected with appropriate infection control precautions for novel virulent SARS-CoV-2 viruses and
sent to state or local health departments for testing. Viral culture should not be attempted in these
cases unless a BSL 3+ facility is available to receive and culture specimens.
STORAGE AND STABILITY
1. Store the test device at 4 to 30ºC in the original sealed pouch. Do Not Freeze.
2. Kit contents are stable until the expiration date printed on the outer box based on the proper
storage condition.
3. The test device should remain in its original sealed pouch until use.
MATERIALS PROVIDED
- QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test Card (25 devices)
Each device houses a strip incorporated with mouse anti-human IgG antibody
monoclonal antibody and recombinant SARS-CoV-2 S1/RBD protein, and is
packed in an individual foil pouch. - Ampoule Sample buffer: Solution contains salt and detergent (25 Ampoules – if provided in Ampoule mode)
- Buffer Sample buffer: Solution contains salt and detergent (1 bottle if provided in bottle mode)
- 10 μL capillary sample pipet
- Instructions for Use (1 copy)
MATERIALS REQUIRED BUT NOT SUPPLIED
1. Safety lancet
2. Serum: Vacutainer tube, or other appropriate tube, without anticoagulant
3. Volumetric pipettor
4. Timer or clock
5. Personal Protective Equipment
QUALITY CONTROL
1. The control band is an internal reagent and procedural control. It will appear if the test has been
performed correctly and the reagents are reactive.
2. Good laboratory practice recommends the daily use of control materials to validate the reliability of
the device. Control materials, which are not provided with this test kit, may be commercially
available.
SPECIMEN COLLECTION AND PREPARATION
1. The serum or fingerstick blood should be collected under standard laboratory conditions.
2. Fingerstick sample should be tested immediately after collection. If the assay is not performed
immediately, serum sample can be frozen until the test can be performed. Frozen samples should
be thawed and brought to room temperature before proceeding. The sample performs best when
tested immediately after collection.
3. Sodium azide can be added as a preservative up to 0.1% without affecting the test results.
PROCEDURE

Ampoule Buffer Mode

Bottle Buffer Mode
2. Open the pouch and remove the test card. Once opened, the test card must be used immediately.
3. Label the test card.
4. (Choose one specimen collection method among A or B below)
A. For fingerstick blood: Wipe the complete fingertip of subject’s middle(3rd) or ring(4th) finger with the alcohol wipe or swab, wait until the fingertip has completely dried (minimum 30 seconds); Punch the fingertip with safety lancet and make sure a well-formed drop of blood is present: Use the capillary pipet to draw sample up to the pipet’s black line indicator.


B. For serum: Take up 5 μL of serum sample by volumetric pipettor.
5. Place the sample on the test card as shown in the diagrams below:

Release the sample to the “S1” area indicated by arrow mark.

Release the sample to the “S1” area indicated by arrow mark.
6. Add the buffer to the test card as shown in the diagrams below:

Twist open the provided extraction buffer ampoule at upright position, with notched neck side on top. Squeeze the ampoule to empty extraction buffer into well area marked as “S”.

Add 2 drops of sample buffer to sample well marked as “S”.
7. After 10 minutes read the results. Note: The results after 15 minutes may not be accurate.

1. The test is for in vitro diagnostic use only.
2. The target population for this test are persons who are fully vaccinated (i.e., 2 weeks after one
complete vaccination series) and want to monitor how their vaccine responses hold up over time.
3. The test is limited to the semi-quantitative detection of SARS-CoV-2 neutralizing antibody in
human blood or serum specimen.
4. According to CDC guidance, there is no definitive concentration cut-off level yet for “protective
level” of antibody.
5. Because COVID-19 vaccines are constructed to encode the spike protein, a positive test for the
spike protein IgG could indicate prior infection and/or vaccination.
6. Antibody testing does not evaluate the cellular immune response, which may also play a role in
vaccine mediated protection.
7. Failure to follow the Test Procedure and Interpretation of Results may adversely affect test
performance and/or invalidate the test results.
8. As with all diagnostic tests, a definitive clinical diagnosis should not be based on the result of a
single test but should only be made by the physician after all clinical and laboratory findings have
been evaluated.
INTERPRETATION OF RESULTS
High Level NAb

In addition to the control band, if the color of test band is equal or stronger than that of reference band, it indicates the neutralizing antibody level is at high level.
Low Level NAb

In addition to the control band, if the color intensity of the test band is less than that of reference band, it indicates the neutralizing antibody level is low.
Negative

In addition to the control band, if only a colored reference band appears, it indicates no neutralizing antibody.
Invalid

Invalid

Invalid

The test result is invalid if a colored band does not form in the control region. The sample must be re-tested, using a new test device.
CLINICAL EVALUATION
QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test Card has set the cut-off at 2 μg/mL of humanized anti-RBD IgG.

The analytical cut-off is set at 1.0 μg/mL of humanized anti-RBD IgG antibody. There is no hook effect up to 200 μg/mL.
ACCURACY
Seventy-five (75) samples collected from healthy people prior to December 2019, thirty (30) samples of convalescent serum from infected people and ninety-nine (99) samples from fully vaccinated individuals with various vaccines were tested. The results of convalescent samples were compared with an EUA approved surrogate virus neutralization test (sVNT) kit. The cut-off the sVNT test kit is set at 30% of inhibition of RBD protein binds to ACE-2. All twenty-four (24) samples that have virus inhibition rate 28% or higher showed high antibody level results on QuickProfileTM SARS-CoV-2 Neutralizing Antibody Test Card. The results are summarized in the following table.

Forty-eight (48) fully vaccinated samples were followed at 3 weeks after the first dosage and 2 weeks after the second dosage to monitor the level of antibodies. The results are summarized below.

INTERFERENCE
1. Other infectious diseases
QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test Card has tested the following serum samples with antibody to other viral infections/ diseases: Influenza A Virus IgM positive, Influenza B Virus IgM positive, Respiratory syncytial virus IgM and IgG positive, HBV, HCV, HIV, Respiratory adenovirus IgM and IgG positive, Parainfluenza virus type 1, 2, 3 IgM positive, Legionella pneumophila IgM positive, Chlamydia pneumoniae IgM and IgG positive, Mycoplasma pneumoniae IgG and IgM positive, and Anti-nuclear antibody positive. All the samples showed no effect on the specificity of the assay.
2. Blood compounds
QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test Card has tested samples with high Rheumatoid Factor (RF), Bilirubin, Triglyceride and Hemoglobin. The results showed that these compounds had no effect on the specificity of the assay up to the listed concentrations.
Rheumatoid Factor 80 IU/ml
Bilirubin 342 μmol/L
Triglyceride 37 mmol/L
Hemoglobin 10 mg/mL
3. Common drugs
QuickProfile™ SARS-CoV-2 Neutralizing Antibody Test Card has tested samples with common drugs. The results showed that these drugs had no effect on the specificity of the assay.
Histamine Hydrochloride, Interferon-, Zanamivir, Ribavirin, Oseltamivir, Peramivir, Lopinavir, Ritonavir, Arbidol, Levofloxacin, Azithromycin, Ceftriaxone, Meropenem, Tobramycin.
1. Ania Wajnberg, et al. Robust neutralizing antibodies to SARS-CoV-2 infection persist for months
http://science.sciencemag.org published online October 28, 2020
2. Q.X.Long, et al. Antibody responses to SARS-CoV-2 in patients with COVID-19, Nat.Med. Vol.26
845-848 (2020)
3. Chee Wah Tan, et al. A SARS-CoV-2 surrogate virus neutralization test based on antibodymediated
blockage of ACE2-spide protein-protein interaction, Nature Biotechnology
https://doi.org/10.1038/s41587-020-0631-z.
.
Order direct or ask for more information using the links below
© Coronavirus Diagnostics 2020 | Cookie notice | Privacy policy |