(714b) Bioinspired Silica: A Novel, Green and Biocompatible Drug Delivery System

The development of a drug delivery system (DDS) is essential in many cases to remedy the limitations of free drug molecules. Silica has been of great interest as a DDS, however, their fabrication often involves harsh chemicals and energy intensive laborious methods. This work details the employment of a bioinspired “green” method¹ to develop a one step and one pot method for simultaneous silica synthesis and drug loading.²

Using various drugs, we investigated bio-inspired silica (BIS) as a new DDS and compared it to mesoporous silica; the latter have received much attention for drug delivery applications. The BIS synthesis enables controllable in situ loading of drugs by carefully designing the DDS formulation conditions. Here we systematically studied these conditions and it was found that the drug loading efficiency, loading and release could be enhanced significantly. By identifying ideal formulation conditions for BIS, we produced a DDS that was able to release fivefold more drug per weight of silica when compared with mesoporous silica. BIS was found to be considerably less cytotoxic^2,3 than their current counterparts. Further it was found that, although ∼20% of BIS was able to pass through the gut wall into the bloodstream, it was nonhemolytic (∼2% hemolysis at 500 μg mL^–1) when compared to mesoporous silica (10% hemolysis at the same concentration). Overall for DDS, it was clear that BIS has several advantages over mesoporous silica (ease of synthesis, controllability and lack of hazardous chemicals) as well as being less toxic, making BIS a real potentially viable green alternative to DDS.

References:

1. Patwardhan, S.V. Commun., 47, 7567, 2011.
2. Davidson et al. ACS Biomater. Sci. Eng., 2, 1493, 2016.
3. Steven et al. Mater. Chem. B, 2, 5028, 2014.