White paper 8 | Version 1.0 | Laura Marin, Sarah Parmentier, Kris Ver Donck, Filip Delport
Single domain antibodies (sdAbs) and adhirons are an alternative to conventional antibodies for diagnosis purposes, thanks to their improved capacity for penetrating into tissues. These molecules are currently selected using ELISA. However, this technique does not provide all the kinetic information that is crucial for choosing better binders. To overcome this, we propose the use of FOx BIOSYSTEMS’ fiber-optic surface plasmon resonance
technology (FO-SPR). It is a robust tool that harnesses the power of SPR in an easy-to-use dip-in fiber-optic configuration.
This document describes how to use WHITE FOx to determine the best binder for a specific biomarker. As an example, we used the monomeric form of C-reactive protein (CRP), a protein secreted by the liver that is widely used as a non–specific marker to monitor the development of infection and inflammation. The ability to bind this protein by different single domain antibodies and adhirons was evaluated and kinetics parameters such as association and dissociation constants were also calculated.
The method shown here demonstrates that FO-SPR technology can provide label-free, real-time, fast kinetic characterization, and is superior to traditional assays that can only give end point data.