Design of new heterobifunctional linkers for the covalent binding of biomolecules onto superparamagnetic iron oxide nanoparticles (spions)

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are attractive because of some peculiar properties such as selective separation of biomolecules and cells, automated DNA extraction, targeted gene delivery, use as magnetic resonance contrast agent (MRI), and magnetic field induced hyperthermia for cancer therapy.1a-e For application in biomedicine, SPIONs must be coated with appropriate biomolecules by a stable and easily tunable adsorption. Hence, the need to develop efficient synthetic strategies for the synthesis of novel bio-nanoconjugates is an important and appealing target.2 The strategies used to anchor molecules onto these nanoparticles can involve passive noncovalent adsorption on the outer particle surface or the formation of a more stable covalent bond by using appropriate heterobifunctional linkers between SPION and the biomolecule, in which one functional group of the linker binds specifically the nanoparticle, while the other reacts with the biomolecule in order to form the new nanoconjugate (Figure 1). In this poster, the discovery of a new functional group able to bind specifically the SPIONs is shown, leading to a new class of heterobifunctional linkers for SPIONs functionalization.