Development of iron(II) sulfate nanoparticles produced by hot-melt extrusion and their therapeutic potentials for colon cancer

Abstract Particle size reduction of FeSO 4 (iron(II) sulfate, IS) from micron to nano size was achieved by a combination of hot-melt extrusion (HME) processing and the input of Span 80, Tween 80, and poly(ethylene glycol) (PEG) 6000. Conveying, kneading, and extruding steps of the HME process and a decrease in the surface tension by surfactants were introduced to produce FeSO 4 nanoparticles (NPs) in an aqueous environment. The FeSO 4 -based NPs (ISNPs) in the dispersion were composed of FeSO 4 , Span 80, Tween 80, and PEG 6000 and displayed a hydrodynamic size of 350–400 nm (5–50 mg/mL ISNPs concentration range) and a spherical shape. Considering the feeding ratio of FeSO 4 (20%, w/w) used for preparing the ISNPs, FeSO 4 appears to be wrapped by Span 80, Tween 80, and PEG 6000 according to the results of X-ray photoelectron spectroscopy (XPS) analysis. ISNPs exhibited different thermodynamic properties from those of FeSO 4 itself. In colon adenocarcinoma (Caco-2) cells, the ISNPs group exhibited enhanced antiproliferation and apoptosis potentials compared to the FeSO 4 group ( p