NANOPARTICLES BASED ON MALTOHEPTAOSE-b-POLY (METHYL METHACRYLATE): NOVEL NANOCARRIER FOR DELIVERY OF CHLORINE-ALUMINUM PHTHALOCYANINE IN PHOTODYNAMIC THERAPY

The development of third-generation photosensitizers for use in photodynamic therapy (PDT) is one of the most promising directions in current cancer therapy.1 The nanoparticles based on the block copolymer maltoheptaose-b-poly (methyl methacrylate) (MH-b-PMMA), containing the photosensitizer chlorine-aluminum phthalocyanine (ClAlPc), were obtained through self-assembly in a specific solvent, forming polymeric micelles with a core-shell structure. The MH-b-PMMA@ClAlPc nanoparticles showed a hydrodynamic radius of 41 nm, low polydispersity index, negative zeta potential, high encapsulation efficiency, and optimal stability. Furthermore, MH-b-PMMA@ClAlPc nanoparticles were able to generate cytotoxic singlet oxygen (1O2), showing high singlet oxygen quantum yields (ΦΔ). The drug release profile from MH-b-PMMA@ClAlPc was described by a biphasic model. The assays of cell viability against C. elegans, showed that MH-b-PMMA@ClAlPc nanoparticles did not induce worms lethality at low concentrations, and in tracking analyses it was shown that they were located in intestinal surrounding cells and in minor quantity in the pharyngeal bulb and intestinal lumen. Our findings highlight that MH-b-PMMA@ClAlPc nanoparticles have potential to be employed as novel nanocarriers for hydrophobic photosensitizers in PDT.