Dr Banushan Balansethupathy and his team
High Throughput Octet System: Octet RED384
The need was to identify and characterise high affinity ligands for use in simple point-of-care diagnostic devices, to support the global effort to combat the current COVID-19 (SARS-CoV-2) pandemic. In order to rise to this challenge, Aptamer Group Ltd have identified several aptamer affinity ligands against the SARS-CoV-2 spike protein S1. Aptamers are nucleic acid-based affinity molecules, isolated and engineered to bind with high affinity and selectivity to a variety of targets, including small molecules, proteins, cells, whole tissues, and in this case, viruses. Once individual ‘monoclonal’ aptamers have been isolated against a specific target (in this case the SARS-CoV-2 spike S1 protein), their binding affinity, specificity and matrix compatibility must be characterised.
The characterisation of aptamers here at Aptamer Group Ltd is carried out by our Molecular Interactions Team (lead by Dr Banushan Balansethupathy) using our Octet RED384 BioLayer Interferometry systems. The Octet RED384 system proved to be a quick and reliable method to test the aptamers against the SARS-CoV-2 spike protein and assess their cross-reactivity with spike proteins from related coronavirus including SARS-CoV and MERS-CoV. We were also able to test and demonstrate that our aptamers function in a buffered saliva sample, using the Octet RED384 system. This is hugely beneficial as knowing that our aptamers can be used in real life samples is essential for the end goal of a point-of-care platform. The Octet system was also invaluable in the identification of pairs of aptamers that can bind to the S1 spike protein at different sites. This ‘scanning’ will enable us to identify aptamers which may be used in a variety of commonly used diagnostic test formats.
The Octet RED384 System offers label-free molecular interaction analysis with state-of-the-art high throughput that facilitates the rapid characterization and development of biologics such as off-rate ranking, binding studies, glycosylation screening or analyte titer.
Aptamer Group is utilizing BLI technology to characterize their aptamers efficiently and in a timely manner. The flexibility and throughput allows characterization of many samples and conditions in parallel. Recently they have used BLI successfully in characterizing a population of aptamer binding protein (S1) from SARS-CoV-2. The experimental setup was also used with saliva samples to develop a new self-testing system for COVID-19. Read more.
Learn more about Aptamer Group