Silica Reservoirs for their Use in the Treatment of Demyelization

Interferon ® and Copaxone ® , two commercial drugs used to treat the demyelization diseases like multiple sclerosis, were adsorbed on nanostructured SBA-15 reservoir. SBA-15 is ordered mesoporous silica normally used as catalytic adsorbent powder, but in this work we occluded the drug in the solid from separate solutions of each drug and then released them in a controlled way. The resultant SBA15-Copaxone and SBA15-Interferone were characterized by means of Infrared spectroscopy, Electron Microscopy, N2 adsorptiondesorption, Thermal-gravimetric analysis and X-ray diffraction techniques. Also, an “in vitro” drug release test was performed using an aqueous medium, the released drug was monitored by Ultraviolet-Visible spectroscopy. The resultant X-ray diffraction patterns and electron micrographs showed the characteristic ordered structures of mesoporous silica nanomaterials. The calculated surface area, pore diameter and pore volume values for the silica containing the drugs decreased approximately a 50% compared to SBA-15 reference values. These observations suggest that the drug molecules occupied the empty spaces inside and on the surface of the samples. The drug release profiles showed two stages, beginning with fast medicament liberation during the first hours, followed by a slow drug release until the end of the test.