Mesoporous Silica Materials in Drug Delivery System: pH/Glutathione- Responsive Release of Poorly Water-Soluble Pro-drug Quercetin from Two and Three-dimensional Pore-Structure Nanoparticles

Abstract

Quercetin (Quer) is one of natural products (pro-drugs), presenting pharmacological properties such as: anti-oxidant, anti-inflammatory and anti-cancer activities. However, poor solubility of the Quer causes its poor bioavailability, and consequently reduces its therapeutic efficiency. To manage this problem, different actions are undertaken, among other drug delivery systems (DDSs) are investigated. The objective of present work was to evaluate potential applications of silica nanoparticles as quercetin nanocarriers and to investigate the influence of pH conditions and glutathione (GSH, as non-redox process) concentrations on quercetin release. Two types of mesoporous silica nanoparticles: MCM-41 (2D arrangement of pores) and KCC-1 (3D arrangement of pores) were synthesized and then functionalized by amino-groups. Immersion-evaporation method was used to load the Quer in nanoparticles. Several analysis techniques were used (e.g. electron microscopy, X-Ray diffraction, Zeta potential, simultaneous thermal analysis-connected to FTIR and many more). Obtained results indicated that both types of silica nanoparticles were successfully loaded with quercetin, and that the Quer present in silica mesopores had a non-crystalline structure. Loading capacity of functionalized MCM-41 was slightly higher than functionalized KCC-1 (29.11 wt% and 26.49 wt%, respectively). This difference could be attributed to the differences in the morphology structures such as surface area and pore volume…