Coarse-grained simulations of nanometer-sized devices for drug delivery

Resumen

In the present thesis, different aspects of micro- and nanogels are studied with help of coarse-grained simulations, that will allow us to understand their behavior in order to be used as drug transporters. For this purpose, the equilibrium absorption of nanometric cosolutes (which could represent drugs, reactants, small globular proteins and other kind of biomacromolecules) inside neutral hydrogels has been studied. We have explored, for different swelling states, the competition between the steric exclusion induced by the crosslinked polymer network constituting the hydrogel, and the solvent-induced short-range hydrophobic attraction between the polymer chains and the cosolute particle. For this purpose, the cosolute partition coefficient is calculated by means of coarse-grained grand canonical simulations, and the results are compared to theoretical predictions based on the calculation of the excluded and binding volume around the polymer chains. The interplay between hydrophobic adhesion and the steric exclusion leads to different behaviors depending on the hydrophobic attraction or the size of the cosolutes.