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SARS-CoV-2 Receptor Binding Domain

Spike protein RBD recombinant, expressed in HEK 293 cells

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COVID-19, SARS-CoV-2, Spike Protein RBD, Spike-ACE2, coronavirus


expressed in HEK 293 cells

Quality Level


≥95% (SDS-PAGE)


lyophilized powder

mol wt

~35 kDa


ELISA: 2 μg/mL (({Functional} RBD binds 50% of the optimal binding RBD-ACE2 ))

shipped in


storage temp.


Related Categories

General description

SARS-CoV-2 belongs to Coronaviridae (CoVs) - a large family of viruses that usually cause mild to moderate upper-respiratory tract diseases.1 CoVs are single-stranded RNA viruses. They have a high mutation rate and are therefore highly diverse.1 Their hosts include human and non-human mammals, as well as birds.1


This product is expressed in human HEK 293 cells as a glycoprotein with a calculated molecular mass of 25 kDa (amino acids 319- 541) and includes a C-terminal polyhistidine tag.


The activity of this product is tested by a functional ELISA. Immobilization of Spike protein Receptor Binding Domain at 2 μg/mL (100 μL/well), allows binding of ACE2, biotin tagged (Cat. No. SAE0171). The half maximal binding (binding which produces 50% of the optimal binding response) is ≤2 μg/mL.

Biochem/physiol Actions

SARS-CoV-2 infects cells which express angiotensin converting enzyme 2 (ACE2).2 ACE2 binds to the viral envelope-associated spike (S) protein as a cellular receptor, following proteolytic cleavage of both S and ACE2 by serine proteases.3 The receptor binding domain (RBD) of S protein is the domain that specifically binds to ACE2.

Physical form

This product is supplied as a lyophilized powder in phosphate buffered saline (PBS), pH 7.4, with no carrier proteins.

Storage and Stability

Store the product at –20 °C. The product retains its activity for at least 2 years as supplied. After initial thawing, it is recommended to store the protein in working aliquots at –20 °C.


Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.

Data presented is the available current product information and provided as-is. This product has not been tested or verified in any additional applications, sample types, including any clinical use. Experimental conditions must be empirically derived by the user. Our Antibody Guarantee only covers tested applications stated herein and conditions presented in our product information and is not extended to publications.

Storage Class

11 - Combustible Solids



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