To study biological interactions of significant importance, we design biomimetic surfaces. For this purpose, we exploit sensitive surface techniques such as quartz crystal microbalance with dissipation monitoring (QCM-D), spectroscopic ellipsometry (SE) and surface plasmon resonance (SPR) and develop different strategies to functionalize gold surfaces providing efficient recognition to the biological partner. The surface functionalization is mainly carried out on self-assembled monolayer (SAM) of alkanethiolates bearing anchoring groups. Strategies include non-covalent attachment (i.e. biotin/streptavidin), host-guest interaction (beta-cyclodextrin/ferrocene or adamentane) and covalent coupling (NHS/EDC coupling, CuAAC). Our approach confers to the functional surfaces a highly specificity due to a background of oligoethyleneglycol (OEG) that suppresses undesired non-specific binding.

For instance, using beta-cyclodextrin/ferrocene system we developed surfaces bearing “RGD” ligand, which recognizes the alphaVbeta3 integrin (more info), for the selective isolation of tumor cells (ChemBioChem 2014 ; J. Mater. Chem. B 2017). This approach allows the design of switchable functionalized surfaces for broad applications in biological research and diagnosis. From a fundamental point of view, we are also interested in developing nanostructured surfaces to study the role of clustering in multivalent interactions, which are involved in different biological processes such as cell and bacteria adhesions and protein recognition.

In parallel, we developed antigenic surfaces for mAb recognition. The CD20 antigen which is a target for immunotherapy of leukemia and lymphoma using the monoclonal antibody (mAb) rituximab was grafted to surfaces via CuAAC. We were able to study the contribution of the statistical rebinding and the bivalent effect of RTX mAb (Anal. Chem. 2020).

Recent collaborations:
R. Richter (University of Leeds, Great Britain)
J.-L. Coll (Institute for Advanced Biosciences, Grenoble)