JOINSTAR® COVID-19 Antigen Rapid Test (Saliva, Sputum and Stool Test)

1 Piece

SKU: M4328 Categories: ,


The Joinstar COVID-19 Antigen Rapid Test provides qualitative detection of SARS-CoV-2 in oropharyngeal saliva, sputum or stool. No invasive sample collection is required to perform the test and is therefore particularly suitable for children, the elderly and people with disabilities.

The sample collection tubes are already pre-filled with the correct amount of buffer solution. The user therefore saves the step of decanting the buffer solution. Since this step is eliminated, the test can also be performed with less potential for error. The Joinstar Antigen Saliva Test has no cross-reactivity and is sensitive to corona mutations. The test result is available after only 15 minutes.

The COVID-19 Rapid Antigen Test (Latex) is suitable for the qualitative detection of novel coronaviruses in saliva, sputum (each from the posterior oropharyngeal region) and stool specimens. It aids in the diagnosis of infection with new types of coronaviruses. The COVID-19 Antigen rapid test (Latex) is intended to be used in conjunction with clinical manifestations and other laboratory test results to aid in the diagnosis of patients with suspected SARS-CoV-2 infection. The test is to be used only by medical personnel. It provides only an initial screening test result and more specific, alternative diagnostic methods should be performed to obtain confirmation of SARS-CoV-2 infection.

The new coronavirus enters human cells through the specific binding of its spike glycoprotein (ligand) to the ACE2 receptor located on the human cell membrane. In this assay, the antibody was replaced by the ACE2 receptor to establish a new ligand-receptor chromatography test kit for rapid detection of the new coronavirus. In clinical practice, the test can be used for rapid detection of SARS-CoV-2 and all mutants. Testing is performed using posterior oropharyngeal saliva, sputum or stool samples from the subject. The test takes only 15 minutes and is much simpler and faster than nucleic acid testing (RT-PCR). The SARS-CoV-2 virus has been shown to evolve into contagious mutants through mutations in S1 proteins (such as D614G) that have stronger binding to ACE2 receptors. Given the current test format based on ACE-2 receptor binding, the test should also be able to detect such mutants.

The test kit contains a nitrocellulose membrane (NC membrane) onto which the rabbit anti-S1 protein of new coronavirus antibody is coated in the T-line region and the polyclonal goat anti-rabbit IgG antibody is coated in the control line region (C). Latex-labeled ACE2 protein and latex-labeled rabbit IgG are embedded in the reagent pad. To perform the assay, three drops of sample are added to the sample well, and the sample flows from the bottom to the top by capillary effect. After a 15-minute incubation, if the patient sample contains the virus, the latex-labeled ACE2 protein is bound by the S1 protein of the virus and then captured by anti-S1 protein antibodies coated on the TLine region. If the sample does not contain the virus, the latex-tagged ACE2 protein will not be captured by anti-S1 protein antibodies applied to the T-line region, therefore no T-line will appear. Regardless of whether the sample contains the virus or not, the latex-labeled rabbit IgG reacts with the polyclonal goat anti-rabbit IgG antibody coated on the control line region (C), and a colored line appears in the control region.

Once the assay is complete, the amount of latex ACE2 protein bound to the T-line is directly proportional to the

concentration of coronavirus in the sample, while the amount of latex bound to control line C does not correlate with the concentration of coronavirus bound to the T-line in the sample.

The limit of detection (LOD) of the COVID-19 antigen rapid test (latex) is 5 ng/ml SARS-COV-2 spike glycoprotein.

The COVID-19 Antigen Rapid Test (Latex) was compared with a leading commercial reagent (PCR). The results show that the COVID-19 Antigen Rapid Test (Latex) has high sensitivity and specificity.

Posterior oropharyngeal saliva specimen:

Method PCR Overall result
COVID-19 Antigen rapid test
Results Positive Negative
Positive 54 0 54
Negative 6 30 36
Overall result
60 30 90

Relative sensitivity: 90,00% (95% CI: 79,49% ~96,24%)
Relative specificity: 100,00% (95% CI: 88,43% ~100,00%)
Accuracy: 93,33% (95% CI: 86,05% ~97,51%)

Sputum sample:

Method PCR Overall result
COVID-19 Antigen rapid test
Results Positive Negative
Positive 37 0 57
Negative 3 30 33
Overall result 60 30 90

Relative sensitivity: 95,00% (95% CI: 86,08% ~98,96%)
Relative specificity: 100,00% (95% CI: 88,43% ~100,00%)
Accuracy: 96,67% (95% CI: 90,57% ~99,31%)

Stool test:

Methode PCR Overall result
COVID-19 Antigen rapid test
Results Positive Negative
Positive 57 0 57
Negative 3 30 33
Overall result 60 30 90

Relative sensitivity: 95,00% (95% CI: 86,08% ~98,96%)
Relative specificity: 100,00% (95% CI: 88,43% ~100,00%)
Accuracy: 96,67% (95% CI: 90,57% ~99,31%)


The COVID-19 rapid antigen test (latex) was also tested against SARS-CoV S1 protein, HCoV-NL63 S1 protein, HCoV-229E S1 protein, HCoV-HKU1 S1 protein, MERS-CoV S1 protein, human RSV (B1) G protein, influenza A H1N1 HA protein, and influenza B HA protein. The results showed no cross-reactivity.

Interfering substances

The following compounds were tested with the COVID-19 rapid antigen test (latex), no interferences were observed.

Interfering substances
Concentration Interfering sub-substances
Triglycerid 50 mg / dl Ascoric acid 20 mg / dl
Hamoglobin 1000 mg / dl Bilirubin 60 mg / dl

Materials provided Quantity per box of 1 Quantity per box of 25
Test cassette
1 Test 25 Tests
Sampling tube 1 piece 25 pieces
Dropper 1 piece 25 pieces
Disposable paper cups 1 piece 25 pieces
Package deployment
1 piece 1 piece

The test is valid for 12 months if all components are packed in the sealed bag, protected from light and stored at 2℃ ~ 30℃ are stored correctly. After filling the reagent package, the test should be performed within one hour.
Please refer to the product package for the manufacturing and expiry date.

Sample collection and preparation

  1. The COVID-19 Antigen rapid test (Latex) can be applied to test oropharyngeal posterior saliva, sputum or stool.
  2. Posterior oropharyngeal saliva: Perform hand hygiene with soap or water/alcohol-based hand disinfection. Open the container. Make a "kruuua" sound from deep in throat to loosen saliva there Then spit saliva (about 2ml) into container. Avoid any saliva contamination of the outer surface of the container. Optimal time to collect the sample: After getting up and before brushing teeth, eating or drinking.
  3. The test should be performed immediately after sample collection. Leave the sample at room temperature for no longer than 2 hours. Samples can be stored at -20°C for up to 1 month prior to testing.
  4. If specimens are to be transported, they should be packaged according to local regulations for transport of etiologic agents.
  5. If samples are stored at -20℃, they must be thawed, brought completely to room temperature and mixed thoroughly before testing. Specimens can be frozen and thawed once. Repeated freezing and thawing should be avoided.

Test method

  1. Posterior oropharyngeal saliva or sputum specimen: loosen the specimen extraction tube and transfer approximately 200mg of fresh saliva or sputum from the container to the specimen extraction tube, mix completely.

  2. Stool sample: Loosen the sample extraction tube to obtain approximately 30 mg of fresh stool (about the size of a match head) with the collection stick. Place the sample stick in the sample extraction tube and shake it until all the stool has dissolved.

  3. Remove the test cassette from the packaging bag, place it on a table, cut off the protrusion of the collection tube and place 3 drops of sample vertically into the sample hole.
  4. Read the result after 15 minutes. If left unread for 20 minutes or longer, results are invalid. A retest is recommended.

Interpretation of the results

Positive (+): Two colored lines appear. One colored line should always be APPE Ar in the control region (C) and another line should be in the T-line region.

* Notice: The intensity of the color in the test line areas may vary depending on the concentration of SARS -CoV-2 in the sample. Therefore, any hue in the test line area should be considered positive and recorded as such.

Negative (-): A colored line appears in the control line area (C).
No line is displayed in the area of the T-line.

Invalid: Control line is not displayed. Insufficient sample volume or improper procedure technique could be reasons for an error. Check the procedure and repeat the test with a new kit. If the problem persists, stop using the test kits immediately and contact your local distributor.

Quality control procedures

Internal procedural controls are included in the test to confirm that sufficient sample volume has been added and that the correct procedural technique has been followed. A colored line in the control area (C) is an indication that the test result is valid. Control standards are not provided with this kit. However, it is recommended that positive and negative controls be tested as a test procedure for good laboratory practice and to verify the test performance

Rapid tests are excluded from return and exchange.

Title Type Size
Declaration-of-Conformity-COVID-19-Joinstar-Antigen-Rapid-Test.pdf application/pdf 610 KB
Gebrauchsanweisung-Joinstar-Antigen-Schnelltest-Latex.pdf application/pdf 452 KB
Technisches-Datenblatt-Speicheltest-4328-25.pdf application/pdf 408 KB
Produktdatenblatt-Speicheltest-4328-25.pdf application/pdf 206 KB