Incorporation of Betulinic Acid into Silica-Based Nanoparticles for Controlled Phytochemical Release

Drug delivery systems are technologies that have been vastly studied and applied to enhance existing therapies. For example, they allow the use of new approaches to already established drugs to improve the application of compounds with biological interest, such as augmenting their bioavailability. Betulinic acid (BA) is a triterpene that possesses interesting biological properties but its low solubility and low bioavailability have limited its applications. This work shows the obtention of BA and its incorporation process into two types of mesoporous silica, SN1(spherical) and SN2 (rod-shaped). Characterization of these materials through infrared, thermal analysis, scanning electron microscopy, and specific surface areas confirmed the presence of this triterpene in this silica matrix. Characterization of the BA release profile demonstrated that the probable mechanism of SN1 nanoparticles is a zero-order release system, whereas SN2 nanoparticles presented a non-Fickian diffusion. These results show the potential use of these nanoparticles as another approach in drug delivery systems for these types of compounds.