Biotecnologia e Biomateriais

Abstrato

Obtaining of SiO₂ Nanostructured Materials for Local Drug Delivery of Methotrexate.

López T, Alvarez M, Arroyo S, Sánchez A, Rembao D and López R

Local delivery of drugs has become an alternative to overcome several side effects of conventional drug administration methods. Because of their novel properties, nanomaterials for controlled drug release have shown enormous potential in the treatment of cancer. In the present work a chemotherapeutic agent, methotrexate (MTX) was encapsulated into a sol-gel SiO2 matrix, as a reservoir for local controlled release in the treatment of a solid brain tumor like Glioblastoma Multiforme (GBM) in an animal model. In order to study interactions between the drug and the SiO2, several physicochemical characterization techniques were carried out. FTIR spectroscopy showed evidence drug incorporation into the silica matrix as the presence of bands at 1504 cm-1, 1604 cm-1 and 1637 cm-1 reveals. This is supported by UV-Vis results, since silica spectrum acquired new features. The materials are mesoporous with a mean pore diameter about 78 Å. In vitro drug release was performed by UV-Vis spectroscopy following the main absorption band of MTX at 348 nm. Drug release was followed and monitored by 16 days. For in vivo evaluation GBM model was performed in Wistar rats once the tumor was developed a reservoir was placed by stereotactic surgery. After three months of tumor inoculation animals treated with MTX-SiO2 survived while in those untreated survival did not exceed 30 days.