Biomedical applications of graphene

Abstract

Graphene exhibits unique 2-D structure and exceptional phyiscal and chemical properties that lead to many potential applications. Among various applications, biomedical applications of graphene have attracted ever-increasing interests over the last three years. In this review, we present an overview of current advances in applications of graphene in biomedicine with focus on drug delivery, cancer therapy and biological imaging, together with a brief discussion on the challenges and perspectives for future research in this field.

Keywords: bioimaging.; biomedical application; biosensing; drug delivery; graphene.

Figure 1

A. Schematic illustration of DOX loading onto NGO-PEG conjugated with anti-CD20 antibody; B. In vitro cytotoxicity at different DOX concentration showing targeted delivery of DOX into specific cells. C. NIR fluorescence image of targeted cells treated with the NGO-PEG of Rituxan. © 2008. Reproduced with kind permission from Springer Science+Business Media and Tsinghua Press.

Figure 2

A. Schematic illustration of synthesizing GO-PEI-DNA complexes via electrostatic interactions. B. Confocal fluorescence images of EGFP transfected HeLa cells using PEI-1.2k (a), GO-PEI-1.2k (b), PEI-10k (c), and GO-PEI-10k (d) at different N/P ratios from 10 to 80. Reproduced by permission of The Royal Society of Chemistry.

Figure 3

A. Scheme showing sequential delivery of siRNA and anticancer drugs by PEI-GO. B. Relative viability of HeLa cells treated with (1) PEI-GO/Bcl-2 targeted siRNA, and (2) PEI-GO/scrambled siRNA, followed by incubation with PEI-GO/DOX. C. IC₅₀ of DOX for the HeLa cells sequentially incubated with (1) PEI-GO/Bcl-2 targeted siRNA and PEI-GO/DOX, and (2) PEI-GO/scrambled siRNA and PEI-GO/DOX. The result indicates that PEI-GO/Bcl-2-targeted siRNA complexes significantly enhanced the cytotoxicity of the PEI-GO/DOX. Copyright Wiley-VCH Verlag GmbH & Co. KGaA. Reproduced with permission.

Figure 4

A. Schematic illustration of PEG functionalized NGS and labeled by Cy7. B. Photos of tumors on mice after various treatments indicated. The laser irradiated tumor on NGS injected mouse was completely destructed. Reprinted with permission from ref.55. Copyright 2010 American Chemical Society.

Figure 5

A. AFM image of the GQDs; B. Fluorescence spectra of aqueous solution of GQDs excited at 375 nm. Inset: aqueous solution of GQDs under UV light; C. cellular imaging of GQDs imaged under 405 nm; D. Cytoxicity of GQDs. Reproduced by permission of The Royal Society of Chemistry.

Figure 6

Schematic illustration of preparation of the Fe₃O₄-GO composites and T₂ weighted cellurlar MR images: (a) HeLa cells (2×10⁵ cells mL^-1) incubated with the Fe₃O₄-GO composites at different concentrations. (b) Fe₃O₄-GO composites (20 μg Fe mL^-1) incubated with HeLa cells at different cell density which Fe₃O₄ NPs formed aggregations on the GO sheets, resulting in a considerable enhanced T₂ relaxivity. Reprinted with permission from ref.33. Copyright 2011 American Chemical Society.

Figure 7

Graphene substrate for osteogenic differentiation. A. Optical image of graphene-coated Si/SiO2 chip, showing the graphene boundary. B. Osteocalcin (OCN) marker showing bone cell formation on the same chip only on the graphene-coated area; C-D. Alizarin red quantification deriving from hMSCs grown for 15 days on substrates with/without graphene as well as with/ without BMP-2. E-H. PET substrate stained with alizarin red showing calcium deposits due to osteogenesis. Reprinted with permission from ref.93. Copyright 2011 American Chemical Society.