Coronavirus SARS-CoV caused an outbreak of severe acute respiratory syndrome (SARS) emerged in Guangdong Province, People’s Republic of China in November 2002. Diagnostic Hybrids Inc. (USA) have subsequently filed a patent application for the use of Sulfobutylether Beta Cyclodextrin (SBECD) in compositions and methods for detecting the presence of SARS-CoV, and for screening anti-SARS coronavirus agents and vaccines. By the invention reducing infection with plus-strand RNA viruses such as SARS-coronavirus could be achieved. The disclosed method was found suitable for increasing the safety of cell cultures that are used in screening clinical samples for respiratory pathogens other than SARS-coronavirus.
SBECD was used to enhance the solubilization, stabilization and lyophilizability of a protease inhibitor (E64d) which was used in the applied bio-assay to inhibit the replication of the human coronavirus. A 20% w/v working SBECD solution was prepared in sterile water. The protease inhibitor E64d was dissolved in the 20% SBECD solution as a 1 mg/ml stock. The stock solution was then serially diluted in the 20% aqueous SBECD solution until the target concentration of E64D was obtained. The resulting culture media contained a constant 3.2% SBECD concentration.
This example is an eminent demonstration how SBECD may be applied in biotechnology to solubilize and stabilize bioactive proteins keeping their functionality. Nevertheless, the patent application was abandoned before being granted and the assignee company (Diagnostic Hybrids Inc.) was later acquired by Quidel Corporation.
As for the relevance of the above application in contemporary context, here is an actual news:
The acquirer company, Quidel has just received a Coronavirus Disease 2019 (COVID-19) Emergency Use Authorization for Medical Devices (In Vitro Diagnostics) from FDA for their Lyra SARS-CoV-2 Assay on 17 March 2020. The product composition is not public, however, according to the related “Instructions for Use document” the kit contains stabilizers of undisclosed type. Should that be SBECD or not, it is a fact that cyclodextrins are always available to meet new challenges in the field of biotechnology.
Compositions And Methods For Detecting Severe Acute Respiratory Syndrome Coronavirus, US patent application US20110223659
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