Core-Shell Mechanocomposites of Drugs with Inorganic Oxides and Hydroxides

The composites of piroxicam and meloxicam with gamma-alumina, aluminium hydroxides (gibbsite and boehmite), alpha and gamma polymorphs of iron(III) oxide having different surface area and morphology were prepared by planetary ball-milling. It has been shown that the initial state of the excipient (specific surface area, particle size and morphology) had a pronounced effect on the formation of the core-shell composites with the drugs and their properties. The X-ray diffraction patterns and IR spectra measured for co-milled samples as well as X-ray photoelectron spectroscopy studies gave evidence that the components of the mixtures interacted with each other and became amorphous, as composites were formed. The drug release from the composites was different as compared with pure drugs, meloxicam and piroxicam behaving differently that can be explained by formation of strong or weak bonds with the active sites of the carriers. In the case of mechanocomposites, the drugs dissolved quickly due to high surface of organic phase in the core-shell composites. The high-porous carriers can serve as the sorbents for the drugs in solution.