pH-responsive carboxymethyl cellulose conjugated superparamagnetic iron oxide nanocarriers

Abstract

In the present study, polyethyleneimine (PEI) coated superparamagnetic iron oxide nanoparticles (SPIONs) having the size of 15 nm in diameter with high magnetic saturation (60 emu/g) have been prepared by co-precipitation method. The synthesized PEI-Fe3O4 nanoparticles have been fully characterized by transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) techniques. The free amine groups on the PEI-Fe3O4 surface has been covalently functionalized with carboxymethyl cellulose (CMC) by the catalysis of N,N'-Dicyclohexylcarbodiimide (DCC) and N, N'-Dimethylpyridin-4-amine (DMAP) coupling to produce CMC-Fe3O4 nanocarriers. The prepared CMC-Fe3O4 nanocarriers have been loaded with a well-known anti-tumor drug doxorubicin (Dox) and investigated its loading and releasing profiles from the nanocarrier. The CMC acted as an excellent nanocarrier for Dox with a loading efficiency ≈ 86%. The drug releasing profile has been studied at different pH values (3.5; 5.5; and 7.4). When the pH of the release medium (phosphate buffer solution) was changed from 7.4 to 5.5 or 3.6, the drug release has been increased which indicates that the drug releasing is pH dependent.