The behavior of water confined in MCM-41 mesopores has been investigated by means of 1H NMR methods as a function of pore filling and temperature. The translational and rotational dynamics of water have been explored in the frame of molecular dynamics simulations providing a good understanding of the solid-state NMR results for three samples with different pore fillings: 10% (MCM-A), 45% (MCM-B), and completely filled (MCM-C). In MCM-B and MCM-C samples one can distinguish the presence of core and surface water, while all water molecules in MCM-A are attached to the surface and do not retain any translational degree of freedom. The activation energies for translational motion (MCM-B and MCM-C) obtained from NMR and MD simulations are in good agreement. For MCM-B and MCM-C samples we relate the decrease in the NMR intensity signal with decreasing temperature mainly with the loss of translational mobility of water molecules, while in the case of MCM-A the decrease is related to the freezing of rotational degrees of freedom.

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Two mesoporous silica materials: MCM-41 and SBA-15 were applied as potential nanocarriers for poorly soluble drug-nimodipine. Drug incorporation was performed using modified adsorption from the solution method and loaded samples before and after washing procedure were studied. The physical properties were verified by: differential scanning calorimetry, X-ray powder diffraction, electron microscopies (SEM/TEM) and Fourier-transform infrared spectroscopy (FT-IR). FT-IR results for bulk nimodipine were interpreted on the basis of first principles calculations (DFT). As a result of encapsulation process, in both matrices nimodipine appeared simultaneously in two forms: crystalline and amorphous, but the first one turned out to be easily removable during washing procedure. The in vitro dissolution and release tests were performed with ultra pure water under supersaturating conditions. The release rate of the amorphous nimodipine from mesoporous silica materials was at least 70 times higher than dissolution rate of bulk drug, thus revealed a potential usefulness of such carrier in future pharmaceutical applications in terms of delivery of poorly soluble drugs.

Computationally-supported NMR and neutron scattering experiments were combined to provide new insights into the structure–dynamics relationship in the most stable polymorph of felodipine.

The dynamics of the pyridinium cation in thiourea pyridinium nitrate inclusion compound has been studied using quasielastic neutron scattering in a wide temperature range (10-350 K). The elastic incoherent structure factor was determined from neutron backscattering and time-of-flight measurements and its analysis allows to describe in detail the geometry of the motions of the pyridinium cation. Our study reveals two types of motion having two different correlation times. The pyridinium cation reorients about the axis perpendicular to its molecular plane over inequivalent threefold potential energy barriers and also executes a faster out-of-plane motion about the axis passing through two opposite atoms of the ring.