Nanometer Resolution Elemental Mapping in Graphene-Based TEM Liquid Cells.
Daniel J KellyMingwei ZhouNick ClarkMatthew J HamerEdward A LewisAlexander M RakowskiSarah J HaighRoman V GorbachevPublished in: Nano letters (2018)
We demonstrate a new design of graphene liquid cell consisting of a thin lithographically patterned hexagonal boron nitride crystal encapsulated on both sides with graphene windows. The ultrathin window liquid cells produced have precisely controlled volumes and thicknesses and are robust to repeated vacuum cycling. This technology enables exciting new opportunities for liquid cell studies, providing a reliable platform for high resolution transmission electron microscope imaging and spectral mapping. The presence of water was confirmed using electron energy loss spectroscopy (EELS) via the detection of the oxygen K-edge and measuring the thickness of full and empty cells. We demonstrate the imaging capabilities of these liquid cells by tracking the dynamic motion and interactions of small metal nanoparticles with diameters of 0.5-5 nm. We further present an order of magnitude improvement in the analytical capabilities compared to previous liquid cell data with 1 nm spatial resolution elemental mapping achievable for liquid encapsulated bimetallic nanoparticles using energy dispersive X-ray spectroscopy (EDXS).
Keyphrases
- high resolution
- induced apoptosis
- ionic liquid
- cell cycle arrest
- single cell
- single molecule
- photodynamic therapy
- mass spectrometry
- magnetic resonance imaging
- magnetic resonance
- cell therapy
- oxidative stress
- big data
- computed tomography
- gold nanoparticles
- electronic health record
- cell proliferation
- tandem mass spectrometry
- mesenchymal stem cells
- fluorescence imaging
- pi k akt
- liquid chromatography
- case control