SARS-CoV-2 Neutralization Antibody Screening ELISA Kit

Principle of the Assay

This assay employs a competitive ELISA format and is uniquely suitable for rapid high-throughput screening of the Anti-SARS-CoV-2 neutralizing antibody in serum or cell culture supernatants. The ACE2 receptor protein has been pre-coated onto a microplate. Controls or samples are pipetted into the wells, and then a horseradish peroxidase-conjugated recombinant SARS-CoV-2 RBD fragment (RBD-HRP) is added to the wells together. The protein-protein interaction between RBD-HRP and ACE2 can be blocked by neutralizing antibodies against SARS-CoV-2 RBD. Following incubation and wash steps, a substrate is added. A colored product is formed in proportion to the amount of SARS-CoV-2 Neutralization Antibody present in the sample. The reaction is terminated by the addition of acid and absorbance is measured at 450nm. The positive control is prepared from SARS-CoV-2 Neutralization Antibody (Mouse IgG) to assure the validity of the results.

Target Information

Coronaviruses are enveloped viruses with a positive-sense RNA genome and with a nucleocapsid of helical symmetry. SARS-CoV-2 has several structural proteins including spike (S), envelope (E), membrane (M), and nucleocapsid (N). The spike protein (S) contains a receptor-binding domain (RBD), which is responsible for recognizing the cell surface receptor, angiotensin-converting enzyme-2 (ACE2). It is found that the RBD of the SARS-CoV-2 S protein strongly interacts with the human ACE2 receptor leading to endocytosis into the host cells of the deep lung and viral replication. The subpopulation of the binding antibodies that can block cellular infiltration and replication of the virus are named neutralizing antibodies. This kit applies to the screening of the SARS-CoV-2 neutralization antibody.

Materials Supplied

Kit Components 96 Wells Quantity/Size
Aluminum pouches with a Microwell Plate coated with Ace2 receptor protein (8×12)
1 plate
Positive Control 2 vials
Negative Control 2 vials
Recombinant SARS-CoV-2 RBD fragment conjugated to horseradish peroxidase (HRP)
2 vials
Diluent Buffer
1 bottle
Wash Buffer Concentrate 20x (PBS with 1% Tween-20) 1 bottle
Substrate Solution 1 bottle
Stop Solution 1 bottle
Adhesive Films 4 pieces
Product insert 1 copy


Storage Store at 2 - 8°C

Performance Characteristics

REPEATABILITY The coefficient of variation of both intra-assay and inter-assay was less than 10%.
SPECIFICITY This assay is specific to SARS-CoV-2 neutralizing antibodies.