Preparation of hybrid materials for controlled drug release

Authors obtained hybrid organic-inorganic materials applied in sustained drug delivery. The materials are ibuprofen as a model drug, hydroxyapatite and three different polymers as supports. Influence of the type of employed polymer, an inorganic carrier, on the properties and drug release profiles was estimated. Flory-Huggins interaction parameters, the dispersive component of surface free energy and acid-base characteristic of the surface were used to assess the behavior of the composites in terms of drug release. The experiments were carried out with the use of inverse gas chromatography (IGC), Fourier transform infrared (FTIR) and ultraviolet (UV) techniques. FTIR and ATR-FTIR spectra were collected. The values of gamma Ds parameter obtained for all investigated materials (excluding poly(L-lactide) (PLA2)) indicate low or medium activity. The strongest interactions (the lowest values of the Flory-Huggins chi'(23) parameter) are observed for PLA2 composition, while the weakest interactions for systems with polyethylene glycol (PEG). Finally, drug release profiles are shown. For materials prepared with Eudragit((R))(EUD) and PLA, the release of drug was much smaller, which corresponds to lower values of Flory-Huggins parameter. The executed experiments allowed the estimation of the properties of prepared composites. Prepared materials present properties required in sustained drug release and may be successfully applied as drug delivery systems.