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SARS-COV-2 Spike RBD Protein

Product Info

Recombinant SARS-COV-2 Spike RBD Protein is expressed from Expi293 with His tag and Avi tag at the C-terminal. It contains Arg319-Asn532.[Accession | QHD43416.1]

Molecular Weight

The protein has a predicted MW of 27 kDa. Due to glycosylation, the protein migrates to 36-40 kDa based on Tris-Bis PAGE result.


Less than 1EU per μg by the LAL method.


> 95% as determined by Tris-Bis PAGE
> 95% as determined by HPLC


Lyophilized from 0.22μm filtered solution in PBS (pH 7.4). Normally 8% trehalose is added as protectant before lyophilization.


Centrifuge tubes before opening. Reconstituting to a concentration more than 100 μg/ml is recommended. Dissolve the lyophilized protein in distilled water.


The product should be stored at -70℃ or -20℃.

Assay Data
Tris-Bis PAGE

SARS-COV-2 Spike RBD on Tris-Bis PAGE under reduced condition. The purity is greater than 95%.


The purity of SARS-COV-2 Spike RBD is greater than 95% as determined by SEC-HPLC.


Immobilized SARS-COV-2 Spike RBD, His Tag at 1μg/ml (100μl/Well) on the plate. Dose response curve for Human ACE2, hFc Tag with the EC50 of 14.5ng/ml determined by ELISA.

SPR Data

Human ACE2, hFc Tag captured on Protein A chip, can bind SARS-COV-2 Spike RBD, His Tag with an affinity constant of 13.8nM as determined in a SPR assay (Biacore T200).


The spike protein (S) of coronavirus (CoV) attaches the virus to its cellular receptor, angiotensin-converting enzyme 2 (ACE2). A defined receptor-binding domain (RBD) on S mediates this interaction.The S protein plays key parts in the induction of neutralizing-antibody and T-cell responses, as well as protective immunity.


S protein RBD; S glycoprotein RBD; Spike protein RBD


(1)Larry J Anderson, Ralph S Baric. Emerging Human Coronaviruses - Disease Potential and Preparedness[J]. N Engl J Med, 2012, 367(19):1850-1852.

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