Influence of the polycation structure on the physicochemical and biological properties of polyplex of heparin and aptamers systems.

Polyplexes are colloidal systems used in medicine so far almost exclusively in gene therapy as non-viral vectors. Polycation-polyanion reactions responsible for their formation can also bind other biologically valuable polyanions (such as heparin). To realize this potential, it is necessary to describe the relationship of the chemical structure of polycations and the size of the resulting polyplex particles and the subsequent biological manifestations. In work presented here, we postulate that in the case of cationic beta-glucans, the presence of a hydroxypropyl group that can be easily added into the macromolecule structure affects the diameter of the resulting polyplex particles. This phenomenon was measured using dynamic light scattering for systems containing heparin and aptamers and cationic derivatives of grain-derived beta-glucans and modified cellulose. The size of polyplex particles and the type of polycation were also correlated to biological parameters: pro proliferative activity and toxicity towards mammalian cells and antifungal activity against selected pathogenic fungal species (e.g. Candida parapsilosis, Cryptococcus neoformans, Trichophyton tonsurans, Fusarium graeminarum, Lomentospora prolificans and Fusarium solani). The polyplex interaction with cells as a function of time has been characterized using fluorescence microscopy. The study included the calorimetry of the polycation-polyanion reactions described here, as well as the overall physicochemical characteristics of the newly synthesized compounds.