CONICET | Buscador de Institutos y Recursos Humanos

Micelleplexes are currently one of the most promising drug carrier systems. They consist of amphiphilic copolymers composed by synthetic block of copolymers called poloxamers (PL) conjugated with synthetic polycations like polyethyleneimine (PEI).Actually, the interest to study those systems associated with cancer therapy has increased, due to its potential to deliver specifically drug and DNA/RNA simultaneously. However, the scientific literature lacks reports on the development of micelleplexes with hydrophobic PL, which could be a more convenient alternative to encapsulate hydrophobic drugs as Doxorubicin. The relevant advantages from the perspective of pharmaceutical technology are: simple manufacturing processes, maintenance of stable nanosystems, and a wide battery of routine techniques for physicochemical and in vitro characterization. In this study, the block copolymers used were PL 61 and L 121, known for their high hydrophobicity. They were conjugated with PEI. For this purpose, a two-step reaction was performed, the first one consisted in the activation of the terminal group OH of PL with Carbonyldiimidazole (CDI) and the second the assembled with the PEI in conditions of inert atmosphere, followed by the purification of the reactants that did not react. The physicochemical characterization of the prepared systems was performed by FT-IR and 1H-NMR spectroscopies. The hydrodynamic diameter and zeta potential were measured by Dynamic light scattering (DLS). The formation of the conjugated copolymer was checked through FT-IR and 1H-NMR, with the inclusion of the amino groups coming from the PEI. Systems presented a hydrodynamic diameter of 200-300 nm and a zeta potential of 12-15. The prepared copolymers proved to be promising to continue in vitro studies and to prepare micelleplexes with doxorubicin and genetic material.