Folic acid decorated magnetic nanosponge: An efficient nanosystem for targeted curcumin delivery and magnetic resonance imaging.

Magnetic drug delivery system is one of the most important strategies for cancer diagnosis and treatment. In this study, a novel theranostic system was fabricated based on cyclodextrin nanosponge (CDNS) polymer anchored on the surface of Magnetite nanoparticles (Fe₃O₄/CDNS NPs) which was then decorated with folic acid (FA) as a targeting agent (Fe₃O₄/CDNS-FA). Curcumin (CUR), a hydrophobic model drug, was next loaded into the cyclodextrin cavity and polymeric matrix of CDNS (Fe₃O₄/CDNS-FA@CUR). The system was fully characterized. The in vitro release study revealed pH-sensitive behavior. Cytotoxicity assays indicated a negligible toxicity for CUR free Fe₃O₄/CDNS-FA NPs against both of M109 cancerous cells and MCF 10A normal cells. CUR-loaded Fe₃O₄/CDNS-FA NPs exhibited higher toxicity against M109 cancerous cells than MCF 10A normal cells (p < 0.05). Fe₃O₄/CDNS-FA@CUR NPs resulted in much more cell viability on normal cells than pure CUR (p < 0.05). Moreover, blood compatibility study showed minor hemolytic activity. In vitro MRI studies illustrated negative signal increase in cells affirming acceptable diagnostic ability of the nanocarrier. The T₂ MR signal intensity for Fe₃O₄/CDNS-FA@CUR NPs in M109 cells was around 2-fold higher than that of MCF 10A cells. This implies two times higher selective cellular uptake of the Fe₃O₄/CDNS-FA@CUR NPs into M109 cell compared to MCF 10A. The multifunctional nanocarrier could be considered as promising candidate for cancer theranostics because of the smart drug release, selective cytotoxicity, suitable hemocompatibility, and proper T₂ MRI contrast efficiency.