White paper 7 | Version 1.0 | Kris Ver Donck, Filip Delport, Laura Marin, Emma Buchet, Kim Stevens
FOx BIOSYSTEMS’ fiber-optic surface plasmon resonance technology (FO-SPR) is a robust tool that harnesses the power of SPR in an easy-to-use dip-in fiber-optic configuration. This document demonstrates the potential of FO-SPR to perform rapid, label-free determination of antibody concentration in complex samples using the WHITE FOx Protein A pre-functionalized sensor probe. Within a few minutes, you can get accurate information on target concentration, and a short second step of a few minutes also allows potency screening with IgG-specific antigens.
We discuss how the FO-SPR label-free assay can provide a performant alternative to conventional methods for characterizing antibodies in crude samples, with minimal processing. This allows for simple protocols and easy experimental setup, while avoiding sample clogging or contamination.
In the example described in this white paper, we use the Protein A sensor probe to quantify human IgG in cell culture supernatants. Concentrations from as low as 0.10 μg/ml up to 100 μg/ml of human IgG are easily detected and measured label-free by FO-SPR through direct binding of IgG to the sensor probe. These sensor probes have the added advantage that they can be regenerated and reused multiple times, with near-complete recovery of signal. Hence, reducing the equipment, time, and costs needed to perform powerful and functional quantification or potency screens.