Transferrin-bearing maghemite nano-constructs for biomedical applications

Superparamagnetic nanoparticles (NPs) are widely used in biomedicine for hyperthermia and magnetic resonance imagery. Targeting them to specific cancerous cells is, therefore, of a great value for therapy and diagnostic. Transferrin and its receptor constitute the major iron-acquisition system in human. The former crosses the plasma membrane within a few minutes by receptor-mediated endocytosis. Thus, transferrin can be a valuable vector for the delivery of NPs to specific cells and across the blood brain barrier. For such a purpose, three different sizes of maghemite NPs (5, 10, and 15 nm) were synthesized by the polyol method, coated with 3-aminopropyltriethoxysilane, and coupled to transferrin by amide bonds. The number of transferrins per nanoparticle was determined. Raw nanoparticles and the transferrin-nanoparticle constructs were characterized. The magnetic properties and the colloidal stability of raw NPs and transferrin-NP constructs were measured and analyzed in relation to their inorganic core size variation. They all proved to be good candidates for nanoparticle targeting for biomedical application. (C) 2015 AIP Publishing LLC.