Controlled release of metoprolol tartrate from nanoporous silica matrices

A series of nanoporous silica matrices (a silica gel matrix and two ordered mesoporous silica) have been investigated as potential carriers for the controlled release of metoprolol tartrate a selective b1 receptor blocker used in the treatment of several diseases of the cardiovascular system. Particular attention was devoted to the optimisation of a reproducible and fast synthetic procedure. The textural properties, structure and chemical nature of the porous surfaces were characterised by N2 physisorption, X-ray diffraction, HR-TEM and FTIR analyses. The delivery profiles were collected in vitro in physiological solution at pH 7.4. It has been possible to observe a close correlation between the drug release kinetic and the textural properties of the carriers.