Modified mesoporous silica nanoparticles coated by polymer complex as novel curcumin delivery carriers

Abstract

The synthesis of mesoporous KIL-2 and KIT-6 nanoparticles (40 and 60 nm, respectively) was performed. Post synthesis procedure was applied for the modification of the initial mesoporous silicas with amino groups. Incipient wetness impregnation or solid state reaction were used for curcumin loading in the parent and amino-modified nanoporous supports. Polymer coating of alternating polymer layers with complementary functionality (k-carrageenan and chitosan) was formed. The parent and drug loaded formulations were characterized by XRD, N2 physisorption, thermal analysis, TEM, AFM, ATR-FT-IR and solid state NMR spectroscopy. Loading of curcumin in the nanocarriers followed by polymer coating made the sustained delivery of curcumin possible. A comparative study on anti-proliferative effect of curcumin loaded into NH2-modified KIT-6 and KIL-2 carriers vs. free drug was performed on a panel of three human cell lines. The most stable complexes of curcumin with protonated amino group ((CH2)3NH3+) are formed when the ammonia group interacts with an O center from the carbonyl group irrespectively of the form of curcumin, while curcumin (in both enol and keto forms) interacts most strongly with the neutral amino group ((CH2)3NH2) via phenolic OH group. On the basis of the obtained results it can be concluded that modified silica particles are promising carriers for controlled delivery of curcumin.