Controlled drug release on amine functionalized spherical MCM-41

MCM-41 silica with spherical morphology and small particle sizes (100 nm) was synthesized and modified by post-synthesis method with different amounts of 3-aminopropyltriethoxysilane (APTES). A comparative study of the adsorption and release of a model drug, ibuprofen, was carried out. The modified and drug loaded mesoporous materials were characterized by XRD, TEM, N2 physisorption, elemental analysis, thermal analysis and FT-IR spectroscopy. A new method was developed for the quantitative determination of amino groups in surface modified mesoporous materials by the ninhydrin reaction. Good correlation was found between the amino content of the MCM-41 materials determined by the ninhydrin method and their ibuprofen adsorption capacity. Amino modification resulted in high degree of ibuprofen loading and slow release rate in comparison to the parent non-modified MCM-41.

Determination of surface amino groups by ninhidrin methodFigure optionsDownload as PowerPoint slideHighlights
► Spherical MCM-41 modified by different amounts of APTES was studied.
► Ibuprofen (IBU) adsorption and release characteristics was tested.
► The ninhydrin reaction was used for the quantitative determination of amino groups.
► Stoichiometric amount of APTES is enough for totally covering the surface with amino groups.
► Good correlation was found between the amino content and IBU adsorption capacity.