Hybrid organic/inorganic materials for drug release systems as new generation of biomaterials: a molecular dynamics study

Biomaterial-based drug delivery systems for controlled drug release are drawing increasing attention due to their possible pharmaceutical and biomedical applications. It is important to control the local administration of drugs, especially when the drug exhibits problems to diffuse in a human body. Thus, in appropriate concentration, it would be released in situ reducing side effects due to interactions with the biological environment after implantation. In recent years, theoretical studies based on molecular mechanics (MM) and molecular dynamics (MD) methods have been performed to investigate the adhesion and surface intermolecular interactions between the amorphous SiO2 surface and the drug molecules ketoprofen and quercetin, anti-inflammatory drugs, considering the role of drug concentration. Interestingly, these theoretical results are in good agreement with experimental data obtained by analyzing, through Fourier Transform Infrared Spectroscopy (FT-IR), the intermolecular interaction between the amorphous silica surface obtained via sol-gel method and the dried SiO2 materials, considering two percentages of these drugs entrapped in silica matrix. Drugs loaded into these amorphous bioactive materials form hydrogen bonds with the silica surface, as found in this theoretical study. Surface interactions in these organic/inorganic materials are essential to have a new generation of biomaterials not only important for biocompatibility, with specific structural and functional properties, but also capable of incorporating anti-inflammatory agents to be released into the human body.