| 1. |
- Bandyopadhyay, Sulalit, et al.
(författare)
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Growing gold nanostructures for shape-selective cellular uptake
- 2018
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Ingår i: Nanoscale Research Letters. - : SpringerOpen. - 1931-7573 .- 1556-276X. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- With development in the synthesis of shape- and size-dependent gold (Au) nanostructures (NSs) and their applications in nanomedicine, one of the biggest challenges is to understand the interaction of these shapes with cancer cells. Herein, we study the interaction of Au NSs of five different shapes with glioblastoma-astrocytoma cells. Three different shapes (nanorods, tetrahexahedra, and bipyramids), possessing tunable optical properties, have been synthesized by a single-step seed-mediated growth approach employing binary surfactant mixtures of CTAB and a secondary surfactant By the use of two-step seed-mediated approach, we obtained new NSs, named nanomakura (Makura is a Japanese word used for pillow) which is reported for the first time here. Spherical Au nanoparticles were prepared by the Turkevich method. To study NS-cell interactions, we functionalized the NSs using thiolated PEG followed by 11-Mercaptoundecanoic acid. The influence of shape and concentration of NSs on the cytotoxicity were assessed with a LIVE/DEAD assay in glioblastoma-astrocytoma cells. Furthermore, the time-dependent uptake of nanomakura was studied with TEM. Our results indicate that unlike the other shapes studied here, the nanomakura were taken up both via receptor-mediated endocytosis and macropinocytosis. Thus, from our library of different NSs with similar surface functionality, the shape is found to be an important parameter for cellular uptake.
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| 2. |
- McDonagh, Birgitte H, et al.
(författare)
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Controlling the self-assembly and optical properties of gold nanoclusters and gold nanoparticles biomineralized with bovine serum albumin
- 2015
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Ingår i: RSC Advances. - : Royal Society of Chemistry. - 2046-2069. ; 5:122, s. 101101-101109
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Tidskriftsartikel (refereegranskat)abstract
- While the size-dependent optical properties of BSA-stabilized gold nanoclusters are well known, the timedependent growth mechanism remains to be described. Herein, we systematically compare two synthesis methods with and without ascorbic acid, and show that tuning of BSA-stabilized gold nanoclusters (AuNCs) of different sizes can be performed without the aid of an extrinsic reducing agent and with good reproducibility. We also show that adding ascorbic acid yields larger BSA-stabilized gold nanoparticles (AuNPs), and that AuNPs can only form above a threshold gold precursor concentration. Using computed tomography, we describe how these biomineralized AuNPs show size-dependent X-ray attenuation. Growth of BSA-stabilized AuNCs and AuNPs, over a range of gold precursor concentrations, was followed with steady-state fluorescence and UV-vis spectroscopy for one week, constituting the first study of its kind. Based on our results, we propose a mechanism for BSA-stabilization of AuNCs and AuNPs that can further aid in selective growth of discrete AuNCs and AuNPs.
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| 3. |
- McDonagh, Birgitte H., et al.
(författare)
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Self-assembly and characterization of transferrin-gold nanoconstructs and their interaction with bio-interfaces
- 2015
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Ingår i: Nanoscale. - : Royal Society of Chemistry (RSC). - 2040-3364 .- 2040-3372. ; 7:17, s. 8062-8070
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Tidskriftsartikel (refereegranskat)abstract
- Transferrin (Tf) conjugated to gold nanoparticles and clusters combine the protein's site-specific receptor targeting capabilities with the optical properties imparted by the nano-sized gold. We have described two different synthesis protocols, one yielding fluorescent Tf-stabilized gold nanoclusters (AuNCs) and one yielding Tf-stabilized gold nanoparticles that exhibit localized surface plasmon resonance. We demonstrate that the synthetic route employed has a large influence both on the gold nanostructure formed, and also on the structural integrity of the protein. A slight protein unfolding allows stronger interaction with lipids, and was found to significantly perturb lipid monolayers. Interactions between the protein-gold nanostructures and three different cell types were also assessed, indicating that the enhanced membrane affinity may be attributed to intercellular membrane differences.
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