We prepared MIL-101 mesoporous metal-organic framework materials with Al, Cr, or Fe as metal centres and with terephthalic or amino-terephthalic acid as organic linker. Into these mesoporous matrices we incorporated large amounts of model drug indomethacin, between 0.9 and 1.1 g of indomethacin per 1 g of MIL-101. We studied the obtained drug-delivery systems by solid-state nuclear magnetic resonance spectroscopy. We employed homonuclear and heteronuclear correlation techniques to yield information about the location of the embedded drug and solvent molecules and about interactions among these molecules. We showed that solvent molecules cannot be efficiently removed from MIL-101. The reasons are the bridging hydoxyl groups, which bind solvent molecules by hydrogen bonds, and the porous system, which comprises spherical cavities with small windows that obstruct diffusion of molecules out of the porous matrix.
COBISS.SI-ID: 5447706