title: RGDS- and TAT-Conjugated Upconversion of NaYF4:Yb(3+)/Er(3+)&SiO2 Nanoparticles: In Vitro Human Epithelioid Cervix Carcinoma Cellular Uptake, Imaging, and Targeting.
abstract: Starting NaYF4:Yb(3+)/Er(3+) nanoparticles with size tuned from 24 to 33 nm were prepared by high-temperature coprecipitation of lanthanide chlorides in high-boiling organic solvents. To enhance colloidal stability in aqueous medium, an aminosilica shell was introduced on the surface by hydrolysis and condensation of tetramethyl orthosilicate and (3-aminopropyl)trimethoxysilane using a reverse microemulsion technique; to form alkyne groups, reaction with 4-pentynoic acid followed. Finally, the cell adhesive and cell penetrating azidopentanoyl-GGGRGDSGGGY-NH2 (RGDS) and azidopentanoyl-GGGRKKRRQRRR-NH2 (TAT) peptides were conjugated to the upconversion particles via Cu(I)-catalyzed alkyne-azide cycloaddition. The concentrations of the peptides bound to the nanoparticle surfaces and amount of adsorbed residual Cu(I) catalyst were determined using an (125)I-radiolabeled RGDS peptide and a (64)Cu(I)-doped catalyst, respectively. Targeting and uptake of the RGDS- and TAT-conjugated NaYF4:Yb(3+)/Er(3+)&SiO2 nanoparticles by human cervix carcinoma HeLa cells were monitored by confocal microscopy. RGDS-conjugated nanoparticle probes were mainly localized on the cell plasma membrane due to specific binding of the peptide to the corresponding integrins. In contrast, the TAT-conjugated nanoparticles were able to cross the cell membrane and accumulate in the cell cytoplasm. Thus, this new peptide bioconjugation approach supported both extra- and intracellular nanoparticle uptake, enabling targeting and imaging of the specific tumor phenotypes.
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovského nám. 2, 162 06 Prague 6, Czech Republic.
authors.forename: Uliana
authors.initials: U
authors.lastname: Kostiv
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovského nám. 2, 162 06 Prague 6, Czech Republic.
authors.forename: Ilya
authors.initials: I
authors.lastname: Kotelnikov
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovského nám. 2, 162 06 Prague 6, Czech Republic.
authors.forename: Vladimír
authors.initials: V
authors.lastname: Proks
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovského nám. 2, 162 06 Prague 6, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Šlouf
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovského nám. 2, 162 06 Prague 6, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Kučka
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic , Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Engstová
authors.affiliation: Institute of Physiology, Academy of Sciences of the Czech Republic , Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Ježek
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovského nám. 2, 162 06 Prague 6, Czech Republic.
authors.forename: Daniel
authors.initials: D
authors.lastname: Horák
keywords: HeLa cells; RGDS peptide; TAT peptide; nanoparticles; upconversion