title: Self-assembled Targeting of Cancer Cells by Iron(III)-doped, Silica Nanoparticles.
abstract: Iron(III)-doped silica nanoshells are shown to possess anin vitrocell-receptor mediated targeting functionality for endocytosis. Compared to plain silica nanoparticles, iron enriched ones are shown to be target-specific, a property that makes them potentially better vehicles for applications, such as drug delivery and tumor imaging, by making them more selective and thereby reducing the nanoparticle dose. Iron(III) in the nanoshells can interact with endogenous transferrin, a serum protein found in mammalian cell culture media, which subsequently promotes transport of the nanoshells into cells by the transferrin receptor-mediated endocytosis pathway. The enhanced uptake of the iron(III)-doped nanoshells relative to undoped silica nanoshells by a transferrin receptor-mediated pathway was established using fluorescence and confocal microscopy in an epithelial breast cancer cell line. This process was also confirmed using fluorescence activated cell sorting (FACS) measurements that show competitive blocking of nanoparticle uptake by added holo-transferrin.
authors.affiliation: University of California San Diego; Dept. of Chemistry and Biochemistry Mail Code 0358, La Jolla, CA 92093.
authors.forename: K K Pohaku
authors.initials: KK
authors.lastname: Mitchell
authors.affiliation: University of California San Diego; Dept. of Bioengineering, La Jolla, CA 92093.
authors.forename: S
authors.initials: S
authors.lastname: Sandoval
authors.affiliation: University of California San Diego; Moores Cancer Center, La Jolla, CA 92093.
authors.forename: M J
authors.initials: MJ
authors.lastname: Cortes-Mateos
authors.affiliation: University of California San Diego; Dept. of Chemical Engineering, La Jolla, CA 92093.
authors.forename: J G
authors.initials: JG
authors.lastname: Alfaro
authors.affiliation: University of California San Diego; Dept. of Chemistry and Biochemistry Mail Code 0358, La Jolla, CA 92093.
authors.forename: A C
authors.initials: AC
authors.lastname: Kummel
authors.affiliation: University of California San Diego; Dept. of Chemistry and Biochemistry Mail Code 0358, La Jolla, CA 92093.
authors.forename: W C
authors.initials: WC
authors.lastname: Trogler
keywords: Silica; nanoparticles; nanoshells; self-targeting; transferrin