5 Pack Novel Coronavirus 15 Min Antigen Detection Kit (Colloidal Gold) 5 Per Box

Principle

The novel coronavirus invades human cells by specifically binding of its spike glycoprotein (ligand) to ACE2 receptor on human cellular membrane with a high affinity (KD measured as 15 nM for the binding of the S protein to the ACE2 receptor), which is 10-20 times stronger than SARS-CoV. Accordingly, we substituted ACE2 receptor for antibody to establish a novel ligand-receptor chromatography test kit for rapid novel coronavirus detection. The sensitivity of the strip to S protein reached 30 nM. In clinical practice, this test strip can be used for rapid detection of sputum and stool samples of patients, which only takes 10-15 minutes, much easier and faster than nucleic acid testing (RT-PCR). Therefore, this strip is suitable for detection of SARS-CoV-2 and all of its mutants. It has been found that this virus evolved into more contagious mutants through mutations in S1 proteins (such as D614G) that are stronger binding to ACE2 receptors. This means that our detection kit based on ACE2 receptor will be more sensitive to such mutants.

The test kit contains a test strip, in which, on the nitrocellulose (NC) membrane, the rabbit anti-S1 protein of novel coronavirus antibodies is coated at the test area (T), and the goat anti-rabbit IgG polyclonal antibody is coated at the control area (C). Latex-labeled ACE2 protein and Latex-labeled rabbit IgG are embedded in the reagent pad.

During the test, add three drops of the sample, and the sample laterally flows from the bottom to the top under the capillary effect. If the sample contains the virus, the latex-labeled ACE2 protein will be bound by the S1 protein of virus, and then captured by anti-S1 protein antibodies coated on the test area (T), the T line is appeared. If the sample does not contain the virus, the latex-labeled ACE2 protein cannot be captured by anti-S1 protein antibodies coated on the test area (T), therefore, no T line appear. No matter whether there is a novel coronavirus in the sample, the latex-labeled rabbit IgG will be combined with the goat anti-rabbit IgG polyclonal antibody coated on the control area (C). A red latex line will appear in the control area.

At the end of the test, the amount of latex-ACE2 protein bound on the T line is proportional to the concentration of novel coronavirus in the sample, while the amount of latex on the control line C bound is irrelevant to the amount of coronavirus in the sample.