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Starting from simplex drug delivery system, the graphene oxide (GO) and reduced GO (rGO) materials have been developed to be "combo" nanoplatforms containing multiple therapeutic modalities, such as the targeted drug delivery, imaging, as well as photothermal therapy (PTT) due to their distinctive physical/chemical and optical properties including excellent biocompatibility, modifiable active groups, ultra-large surface area, and intense photothermal effect. The graphene-based nanoplatforms were used for the stimuli-responsive nanocarriers, showing excellent therapeutic effects activated by endogenous stimuli including low pH, overexpressed enzymes, biomolecules, elevated glutathione, and exogenous stimuli including light, magnetic/electric field, and ultrasound. More importantly, for multimodal synergistic therapy originated from the enhanced collaborative interactions among several monotherapy types, the obtained remarkable super-additive effects were not the results just through single therapy or their theoretical combination. In this review, the recent progresses of smart graphene-based nanoplatforms for integrated cancer therapy and bio-imaging are presented. Current challenges and future perspectives of graphene-based nanoplatforms in the biomedical field are also discussed. In this review, the recent progresses of smart graphene-based nanoplatforms for integrated tumor therapy and bio-imaging are presented. Current challenges and future perspectives of graphene-based nanoplatforms in the biomedical field are also discussed. [ABSTRACT FROM AUTHOR]

We investigate the optical response of a gold nanocube antenna supported by a high-permittivity dielectric nanocuboid substrate and propose schemes for broadband tailoring of its plasmonic resonances via alteration in image-charge screening. Based on finite-element-method (FEM) simulations-in agreement with filtered-coupled-dipole-approximations (FCDA)-we explore the tunability and spectral evolution of the substrate-supported nanocube's hybridized plasmon modes as functions of the relative permittivity and dimensions of the dielectric substrate. Besides numerical calculations, we also derive simple analytical expressions using image-charge theory to readily estimate the resonance spectral shift-gauging the intense particle-substrate interaction-for a substrate-supported nanocube. Strong localized electric field, around the nanocube's vertices and edges near the substrate, is observed due to the image charges induced in the substrate by the coupled bonding mode arising from hybridization of the primitive dipolar and quadrupolar modes of the nanocube. By introducing slots on the dielectric substrate in the areas around the nanocube's edges where electric field is highly concentrated, we achieve substrate's surface-mediated wideband tunability of plasmonic resonance as functions of the geometric parameters of the slots while maintaining the overall dimensions and material of the nanocuboid substrate. These slots enable dynamic tunability of plasmon resonance by placing graphene flakes on them, which facilitates electrical tailoring of nanocube's plasmon resonance over visible and near-infrared regions. Thus, these proposed schemes would allow one to widely tune the optical responses of any plasmonic nanoantennas using a slotted finite high-permittivity-dielectric substrate for numerous applications in nanophotonic integrated circuits and plasmonic devices. [ABSTRACT FROM AUTHOR]

• Heat conduction enhanced flexible phase change material (FPCM) film is developed. • FPCM film thermally manages the compact electronics almost without occupying space. • FPCM film lowers the chip's temperature with a maximum drop of 14.3 ℃. • Graphene film enhances heat transfer of FPCM film along the inplane direction. • Latent heat capacity utilization rate of the FPCM film is significantly increased. Strict internal space limit of compact electronics makes it hard to use cooling tubes for the forced convection or phase change materials (PCMs) block to thermal control. In this paper, two types of high thermal conductive flexible phase change material (FPCM) with latent heat of 160.2 J/g and 153.1 J/g were developed into film morphology with the thickness of 0.4 mm, and were used to manage heat dissipation of the compact electronics. The experimental results show that temperature of the analog chip controlled by FPCM film is indeed lowered with a maximum drop of 14.3 ℃. The promotion of FPCM's thermal conductivity increases the effective thermal control time but still is insufficient to the heat dissipation along the inplane direction inside electronics. Therefore, the graphene film with plane thermal conductivity of 1500 W/m·K is employed to fabricate the composite heat-diffusion FPCM film to enhance transverse heat transfer. The result shows the latent heat capacity utilization rate of the FPCM film and heat diffusion area along the inplane direction are significantly increased with the extension of thermal control time by 32.4% at 3.2 W. These results are expected to provide a strong basis for the implementation and optimization of phase change thermal management technique in compact electronic device. [ABSTRACT FROM AUTHOR]

Abstract: The direct imaging of individual atoms within the cellular context holds great potential for understanding the fundamental physical and chemical processes in organisms. Here, a novel approach for imaging of electrically insulated biological cells by introducing a graphene encapsulation approach to “disguise” the low‐conductivity barrier is reported. Upon successful coating using a water‐membrane‐based protocol, the electrical properties of the graphene enable voltage pulsing field evaporation for atom probe tomography (APT). Low conductive specimens prepared from both Au nanoparticles and antibiotic‐resistant bacterial cells have been tested. For the first time, a significant graphene‐enhanced APT mass resolving power is also observed confirming the improved compositional accuracy of the 3D data. The introduction of 2D materials encapsulation lays the foundation for a breakthrough direction in specimen preparation from nanomembrane and nanoscale biological architectures for subsequent 3D near‐atomic characterization. [ABSTRACT FROM AUTHOR]