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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 SEC-HPLC


Lyophilized from 0.22μm filtered solution in PBS (pH 7.4). Normally 5 % 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 0.5μg/ml (100μl/Well) on the plate. Dose response curve for Human ACE2,hFc Tag with the EC50 of 24.9ng/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 epidermal growth factor receptor (EGFR) is overexpressed in a variety of human epithelial tumors, often as a consequence of gene amplification. Tumors with EGFR gene amplification frequently contain EGFR gene rearrangements, with the most common extracellular domain mutation being EGFRvIII. This mutation leads to a deletion of exons 2-7 of the EGFR gene and renders the mutant receptor incapable of binding any known ligand.


S protein RBD,Spike glycoprotein Receptor-binding domain,S glycoprotein RBD,Spike protein RBD


(1) Karasu Ebru E, Nilsson Bo B, Köhl Jörg J, Lambris John D JD

(2)Front Immunol 2019-05-03 994 10

(3)Zelek Wioleta M WM, Taylor Philip R PR

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