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Fabrication of graphene-isolated-Au-nanocrystal nanostructures for multimodal cell imaging and photothermal-enhanced chemotherapy.

Bian X, Song ZL, Qian Y, Gao W, Cheng ZQ, Chen L, Liang H, Ding D, Nie XK, Chen Z, Tan W - Sci Rep (2014)

Bottom Line: First, as surface-enhanced-Raman-scattering substrates, GIANs quench background fluorescence and reduce photocarbonization or photobleaching of analytes.Controlled release of DOX molecules from GIANs is achieved through NIR heating, significantly reducing the possibility of side effects in chemotherapy.The GIANs have high surface areas and stable thin shells, as well as unique optical and photothermal properties, making them promising nanostructures for biomedical applications.

View Article: PubMed Central - PubMed

Affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University, Changsha, 410082, China.

ABSTRACT
Using nanomaterials to develop multimodal systems has generated cutting-edge biomedical functions. Herein, we develop a simple chemical-vapor-deposition method to fabricate graphene-isolated-Au-nanocrystal (GIAN) nanostructures. A thin layer of graphene is precisely deposited on the surfaces of gold nanocrystals to enable unique capabilities. First, as surface-enhanced-Raman-scattering substrates, GIANs quench background fluorescence and reduce photocarbonization or photobleaching of analytes. Second, GIANs can be used for multimodal cell imaging by both Raman scattering and near-infrared (NIR) two-photon luminescence. Third, GIANs provide a platform for loading anticancer drugs such as doxorubicin (DOX) for therapy. Finally, their NIR absorption properties give GIANs photothermal therapeutic capability in combination with chemotherapy. Controlled release of DOX molecules from GIANs is achieved through NIR heating, significantly reducing the possibility of side effects in chemotherapy. The GIANs have high surface areas and stable thin shells, as well as unique optical and photothermal properties, making them promising nanostructures for biomedical applications.

Show MeSH
Raman properties of GIANs.(a) Raman spectrum (excitation at 632 nm) of GIANs showing the G and D bands of graphitic carbon. (b) Raman imaging of MCF-7 cells with and without GIAN staining. BF: bright field, scale bar: 10 μm. (c) Raman spectra of R6G molecules, with and without GIAN, and with Au nanoparticles, respectively.
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f2: Raman properties of GIANs.(a) Raman spectrum (excitation at 632 nm) of GIANs showing the G and D bands of graphitic carbon. (b) Raman imaging of MCF-7 cells with and without GIAN staining. BF: bright field, scale bar: 10 μm. (c) Raman spectra of R6G molecules, with and without GIAN, and with Au nanoparticles, respectively.

Mentions: GIANs have unique Raman scattering properties. Two prominent bands can be observed around 1325 and 1595 cm−1 (Fig. 2a), corresponding to the D and G Raman vibrational modes of graphitic carbon shells, respectively. The high intensity (relative to the G peak) Raman D peak reflects the high strain of the graphite shells as a result of the deformation of the flattened graphene encapsulating the Au nanocrystals. The GIAN has a strong and simple resonance Raman signature and can be utilized as a good Raman tag for cell imaging. Compared to organic Raman active molecules, GIANs, as graphitic nanomaterials, have enormous Raman scattering cross sections (~10−21 cm2 sr−1 molecule−1) and are much more stable based on their inorganic structure6.


Fabrication of graphene-isolated-Au-nanocrystal nanostructures for multimodal cell imaging and photothermal-enhanced chemotherapy.

Bian X, Song ZL, Qian Y, Gao W, Cheng ZQ, Chen L, Liang H, Ding D, Nie XK, Chen Z, Tan W - Sci Rep (2014)

Raman properties of GIANs.(a) Raman spectrum (excitation at 632 nm) of GIANs showing the G and D bands of graphitic carbon. (b) Raman imaging of MCF-7 cells with and without GIAN staining. BF: bright field, scale bar: 10 μm. (c) Raman spectra of R6G molecules, with and without GIAN, and with Au nanoparticles, respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4151100&req=5

f2: Raman properties of GIANs.(a) Raman spectrum (excitation at 632 nm) of GIANs showing the G and D bands of graphitic carbon. (b) Raman imaging of MCF-7 cells with and without GIAN staining. BF: bright field, scale bar: 10 μm. (c) Raman spectra of R6G molecules, with and without GIAN, and with Au nanoparticles, respectively.
Mentions: GIANs have unique Raman scattering properties. Two prominent bands can be observed around 1325 and 1595 cm−1 (Fig. 2a), corresponding to the D and G Raman vibrational modes of graphitic carbon shells, respectively. The high intensity (relative to the G peak) Raman D peak reflects the high strain of the graphite shells as a result of the deformation of the flattened graphene encapsulating the Au nanocrystals. The GIAN has a strong and simple resonance Raman signature and can be utilized as a good Raman tag for cell imaging. Compared to organic Raman active molecules, GIANs, as graphitic nanomaterials, have enormous Raman scattering cross sections (~10−21 cm2 sr−1 molecule−1) and are much more stable based on their inorganic structure6.

Bottom Line: First, as surface-enhanced-Raman-scattering substrates, GIANs quench background fluorescence and reduce photocarbonization or photobleaching of analytes.Controlled release of DOX molecules from GIANs is achieved through NIR heating, significantly reducing the possibility of side effects in chemotherapy.The GIANs have high surface areas and stable thin shells, as well as unique optical and photothermal properties, making them promising nanostructures for biomedical applications.

View Article: PubMed Central - PubMed

Affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University, Changsha, 410082, China.

ABSTRACT
Using nanomaterials to develop multimodal systems has generated cutting-edge biomedical functions. Herein, we develop a simple chemical-vapor-deposition method to fabricate graphene-isolated-Au-nanocrystal (GIAN) nanostructures. A thin layer of graphene is precisely deposited on the surfaces of gold nanocrystals to enable unique capabilities. First, as surface-enhanced-Raman-scattering substrates, GIANs quench background fluorescence and reduce photocarbonization or photobleaching of analytes. Second, GIANs can be used for multimodal cell imaging by both Raman scattering and near-infrared (NIR) two-photon luminescence. Third, GIANs provide a platform for loading anticancer drugs such as doxorubicin (DOX) for therapy. Finally, their NIR absorption properties give GIANs photothermal therapeutic capability in combination with chemotherapy. Controlled release of DOX molecules from GIANs is achieved through NIR heating, significantly reducing the possibility of side effects in chemotherapy. The GIANs have high surface areas and stable thin shells, as well as unique optical and photothermal properties, making them promising nanostructures for biomedical applications.

Show MeSH