Département de chimie moléculaire

There is a growing interest in isolating tumor cells from biol. samples. Considering that circulating tumor cells can be rare in blood, it appears challenging to capture these cells onto a surface with high selectivity and sensitivity. In the present paper, we describe the design of functionalized surfaces aimed at selectively capturing tumor cells by using an RGD peptide ligand with either a tetrameric or a monomeric presentation. $\beta$-Cyclodextrin-coated self-assembled monolayers were used as platforms for the binding of RGD ligands endowed with a redox ferrocene cluster. The dissocn. of the inclusion complex on the surface accounts for the release of the captured cells upon the electrochem. oxidn. of ferrocene. For this purpose, we detd. suitable RGD densities for both monovalent and tetravalent ligand presentations. The results indicate that the clustered RGD architecture efficiently improves selective cell capture at a very low RGD surface d. (∼10 RGD per $μ$m2) compared to the monovalent presentation (∼1000 RGD per $μ$m2). [on SciFinder(R)]