Cellular uptake of folate-conjugated lipophilic superparamagnetic iron oxide nanoparticles

Abstract

We prepared five folate-conjugated lipophilic superparamagnetic iron oxide nanoparticles (F-5-LipoSPIONs, 5.5 and 11 nm) and investigated their cellular uptake with KB cells, which is one of the representative folate-receptor over-expressing human epidermoid carcinoma cells, using MRI. The cellular uptake tests with the respective 5.5 and 11 nm F-5-LipoSPIONs at a fixed particle concentration showed appreciable amount of receptor-mediated uptakes and the specificity was higher in 5.5 nm SPIONs, due to its higher folic acid (FA) density, without inhibition. However, the numbers of the particles taken up under FA inhibition were similar, irrespective of their sizes. (C) 2009 Elsevier B.V. All rights reserved.