In this work, we present results for loading of well-defined binary systems (cocrystal, solid solution) and untreated materials (physical mixtures) into the voids of MCM-41 mesoporous silica particles employing three different filling methods. The applied techniques belong to the group of "wet methods" (diffusion supported loading -DiSupLo) and "solvent-free methods" (mechanical ball-mill loading -MeLo, thermal solvent free -TSF). As probes for testing the guest1-guest2 interactions inside the MCM-41 pores we employed the benzoic acid (BA), perfluorobenzoic acid (PFBA), and 4-fluorobenzoic acid (4-FBA).The guests intermolecular contacts and phase changes were monitored employing magic angle spinning (MAS) NMR Spectroscopy techniques and powder X-ray diffraction (PXRD). Since mesoporous silica materials are commonly used in drug delivery system research, special attention has been paid to factors affecting guest release kinetics. It has been proven that not only the content and composition of binary systems, but also the loading technique have a strong impact on the rate of guests release. Innovative methods of visualizing differences in release kinetics are presented.

In this work a relationship between the crystal form and morphology and rheological properties of peptide-based hydrogels is examined. We show, that under favorable circumstances a correlation between a starting solid material and a self-assembly processes in solution can exist, leading to different properties of a resulting soft matter. This observation, together with an in-depth analysis of the influence of stereochemistry of self-assembled (ll) and (dl) Tyr-Tyr cyclic dipeptides (cYY) on the observed relationship between gelation and crystallization allowed us to gain a deeper understanding of the peptide hydrogelation processes at a molecular level, using liquid state NMR, rheological studies and scanning electron microscopy. In the course of our studies, several crystal forms of (ll)-cYY has been discovered and described in details using single crystal X-ray diffraction, as well as advanced solid state NMR, X-ray diffraction of powders, thermal analysis, FTIR, circular dichroism and crystal structure prediction (CSP) calculations. Subsequently, we found that while (ll)-cYY easily assembles into hydrogels with different properties depending on the starting solid form, (dl)-cYY always precipitated as one crystal form in the tested conditions. Molecular-level justification for this observation is given.