Novel heteroleptic ruthenium caged compounds: synthesis, spectral properties and attachment to SiO2 nanoparticles

ROLANDO M. CARABALLO; YAMILI TOUM; PABLO ROSI; ALEJANDRO WOLOSIUK; LUIS M. BARALDO

Santiago de Chile

Congreso; I-APS meeting; 2016

I-APS

Ruthenium polypyridines have been extensively studied, and their photophysical properties are well known.1 Because of these properties, they have been widely used in different applications, like photocatalysis, sensing, energy conversion and photodynamic therapy. A group of these complexes, of general formula [Ru(bpy)2X2]n+ (bpy= 2,2?-bipyridine, X= a labile ligand) has proved to be very effective in the photoliberation of molecules of biological interest (caged compounds) due to the very well established photolabile nature of binding ligand X.2 On the other hand, silica nanoparticles are one of the preferred vehicles for different in vivo applications, like drug delivery.3 These nanoparticles are also well suited for surface functionalization. In this work we present the synthesis and characterization of the complexes [Ru(bpy)(dcbpy)(py)2]2+ and [Ru(dcbpy)2(py)2]2+ (dcbpy= 4,4?-dicarboxy-2,2?-bipyridine, py= pyridine) and the study of their photochemical properties. These compounds can be attached to the surface of silica nanoparticles through a covalent, amide bond, transferring their properties to the surface. In order to proof this, we synthesized and characterized [Ru(bpy)2(dcbpy)]2+@SiO2 fluorescent nanoparticles. Their photophysical and photochemical behaviour suggests these systems could be the basis of a family of caged compounds that are able to release molecules from surface.