Fluorinated dendritic silicon (IV) phthalocyanines nanoparticles: Synthesis, photoinduced intramolecular energy transfer and DNA interaction

Abstract

Two series of fluorinated and non-fluorinated dendritic silicon (IV) phthalocyanines with cyano/nitro/ester terminal functionalities have been synthesized. Their structures were characterized by elemental analysis, FT-IR, 1H NMR and ESI-MS. The effects of fluorinated groups and terminal functionalities properties on the photophysical properties, photoinduced intermolecular electron transfer and intramolecular energy transfer of silicon phthalocyanines were compared. In order to endow water soluble and biocompatibility to these silicon phthalocyanines, an amphiphilic diblock copolymer polyethylene glycol monomethyl ether–polycaprolactone was used to encapsulate these silicon phthalocyanines to form fluorinated and non-fluorinated dendritic silicon phthalocyanines nanoparticles. The binding model between the fluorinated dendritic silicon phthalocyanines nanoparticles and calf thymus DNA was studied by UV–Vis and fluorescence spectroscopic method. The photocleavage DNA activities of three fluorinated dendritic silicon phthalocyanines nanoparticles were compared and the possible cleavage mechanism was proposed.