Series s strepavidin sa chip

Antibody binding to SARS-CoV-2 S protein ectodomains was assessed on a Biacore T-200 (Cytiva, MA, formerly GE Healthcare) with HBS buffer supplemented with 3 mM EDTA and 0.05% surfactant P-20 (HBS-EP+, Cytiva, MA). Assays were performed at 25°C. S protein variants were captured on a Series S Strepavidin (SA) chip (Cytiva, MA) coated at 100 nM (60s at 10μL/min). Fabs were injected at concentrations ranging from 0.625 nM to 800 nM (prepared in a 2-fold serial dilution manner) over the S proteins using the single cycle kinetics mode with 5 concentrations per cycle. The surface was regenerated after the last injection with 3 pulses of a 50mM NaoH + 1M NaCl solution for 10 seconds at 100μL/min. Sensogram data were analyzed using the BiaEvaluation software (Cytiva, MA)

Binding experiments were performed using SPR on a Biacore T-200 (Cytiva, MA, formerly GE Healthcare) with HBS buffer supplemented with 3 mM EDTA and 0.05% surfactant P-20 (HBS-EP+, Cytiva, MA). All binding assays were performed at 25°C.
Spike variants were captured on a Series S Strepavidin (SA) chip (Cytiva, MA) coated at 200 nM (120 s at 5 μL/min). Fabs were injected at concentrations ranging from 0.5 nM to 8 nM (prepared in a 2-fold serial dilution manner) over the S proteins using the single cycle kinetics mode with 5 concentrations per cycle. The surface was regenerated after the last injection with 3 pulses of a 50 mM NaoH + 1M NaCl solution for 10 s at 100 μL/min.
RBD binding to IgG’s was assessed using a Series S CM5 chip (Cytiva, MA) which was labeled with anti-human IgG (fc) antibody using a Human Antibody Capture Kit (Cytiva, MA). IgGs were then coated at 200 nM (120 s at 5 μL/min). RBDs were injected at concentrations ranging from 0.5 nM to 40 nM (prepared in a 2-fold serial dilution manner) over the antibodies using the single cycle kinetics mode with 5 concentrations per cycle. The surface was regenerated after the last injection with 3 pulses of a 3 M MgCl₂ solution for 10 s at 100 μL/min.