title: Cellular uptake of gold nanoparticles passivated with BSA-SV40 large T antigen conjugates.
abstract: Internalization and subcellular localization in HeLa cells of gold nanoparticles modified with the SV40 large T antigen were quantified using inductively coupled plasma optical emission spectroscopy (ICP-OES). Internalization was monitored as a function of incubation time, temperature, nanoparticle diameter, and large T surface coverage. Increasing the amount of large T peptides per gold nanoparticle complex, by either increasing the coverage at constant nanoparticle diameter or by increasing the nanoparticle diameter at constant large T coverage, resulted in more cellular internalization. In addition, nuclear fractionation was performed to quantify nuclear localization of these complexes as a function of large T coverage. In contrast to our prior qualitative investigations of nuclear localization by video-enhanced color differential interference contrast microscopy (VEC-DIC), ICP-OES was able to detect nanoparticles inside fractionated cell nuclei. Although increasing the large T coverage was found to afford higher cell internalization and nuclear targeting, quantitative evaluation of cytotoxicity revealed that higher large T coverages also resulted in greater cytotoxicity. The ICP-OES and nuclear fractionation techniques reported here are valuable tools that can add important quantitative information to optical and electron imaging methods such as VEC-DIC and transmission electron microscopy regarding the fate of nanoparticles in cells.
authors.affiliation: Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Ryan
authors.forename: K Wesley
authors.initials: KW
authors.lastname: Overton
authors.forename: Molly E
authors.initials: ME
authors.lastname: Speight
authors.forename: Christine N
authors.initials: CN
authors.lastname: Oldenburg
authors.forename: LiNa
authors.initials: L
authors.lastname: Loo
authors.forename: Wayne
authors.initials: W
authors.lastname: Robarge
authors.forename: Stefan
authors.initials: S
authors.lastname: Franzen
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Feldheim
mesh_terms: D000952:Antigens, Polyomavirus Transforming / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D053768:Metal Nanoparticles; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D000952:Antigens, Polyomavirus Transforming; D012710:Serum Albumin, Bovine; D006046:Gold