Solvent effects in the development of a drug delivery system for 5-fluorouracil using magnetic mesoporous silica nanoparticles

5-Fluorouracil (5-FU), an anticancer drug, was loaded into magnetic iron oxide/mesoporous silica nanocomposites (m-MCM-41) with and without aminopropyl functionalization using three different solvents (water, water/acetone, dimethyl sulfoxide). The parent and the drug-loaded samples were characterized using physicochemical techniques, such as powder X-Ray diffraction (pXRD), nitrogen adsorption-desorption isotherms and thermogravimetric analysis (TGA). Fourier Transform Infrared spectroscopy (FT-IR) and solid state Nuclear Magnetic Resonance (ssNMR) spectroscopy techniques were used to obtain molecular level insights into the loading of 5-FU into m-MCM-41 with different solvents and surface functionalization. The loading and release characteristics of 5-FU from m-MCM-41 depended on the solvent polarity and the surface functionalization of the host. The chemical insights provided by this study can be used in the future design and development of magnetic mesoporous silica nano composites for theranostic applications. (C) 2016 Elsevier Inc. All rights reserved.