New Hybrid Multicomponent Selenium-Containing Nanosystems for Photodynamic Therapy

Comparative studies of new double and triple selenium-containing nanosystems based on a Photoditazine photosensitizer and amphiphilic molecular brushes (graft copolymers) with a polyimide or cellulose backbone and polymethacrylic acid side chains have been performed by atomic force microscopy and UV–visible spectroscopy. The influence of the structure and topology of the graft copolymers on the morphological and spectral characteristics of amphiphilic molecular brushes loaded with selenium nanoparticles and Photoditazine has been established. It is found that amphiphilic molecular brushes prevent the association of the selenium nanoparticles in solution, forming predominantly discrete spherical nanostructures. It is shown that for a double selenium-containing nanodispersion obtained on the brush with a polyimide main chain with a polymerization degree of the side chains of polymethacrylic acid m = 180, in addition to spherical discrete nanostructures, “capsules” of 200–400 nm in size are also observed. It is suggested that formation of the hybrid multicomponent selenium-containing nanostructures occurs mainly due to the steric stabilization of selenium nanoparticles by brush macromolecules and their incorporation according to the type of metal-porphyrin complexes. Based on UV–visible spectroscopy data, the band gap energy and the diameter of the selenium nanoparticles for hybrid multicomponent selenium-containing nanostructures have been calculated.