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Park J, Jeong H, Noh N, Park JS, Ji S, Kang S, Huh Y, Hyun J, Yuk JM. Single-Molecule Graphene Liquid Cell Electron Microscopy for Instability of Intermediate Amyloid Fibrils. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2309936. [PMID: 38016113 DOI: 10.1002/adma.202309936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/27/2023] [Indexed: 11/30/2023]
Abstract
Single-molecule techniques are powerful microscopy methods that provide new insights into biological processes. Liquid-phase transmission electron microscopy (LP-TEM) is an ideal single-molecule technique for overcoming the poor spatiotemporal resolution of optical approaches. However, single-molecule LP-TEM is limited by several challenges such as electron-beam-induced molecular damage, difficulty in identifying biomolecular species, and a lack of analytical approaches for conformational dynamics. Herein, a single-molecule graphene liquid-cell TEM (GLC-TEM) technique that enables the investigation of real-time structural perturbations of intact amyloid fibrils is presented. It is demonstrated that graphene membranes significantly extend the observation period of native amyloid beta proteins without causing oxidative damage owing to electron beams, which is necessary for imaging. Stochastic and time-resolved investigations of single fibrils reveal that structural perturbations in the early fibrillar stage are responsible for the formation of various amyloid polymorphs. The advantage of observing structural behavior in real time with unprecedented resolution will potentially make GLC-TEM a complementary approach to other single-molecule techniques.
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Affiliation(s)
- Jungjae Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Hyeongseop Jeong
- Electron Microscopy Research Center, Korea Basic Science Institute (KBSI), Chungcheongbuk-do, Cheongju-si, 28119, Republic of Korea
| | - Namgyu Noh
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Ji Su Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Sanghyeon Ji
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Sung Kang
- Analysis and Assessment Research Center, Research Institute of Industrial Science and Technology (RIST), 67 Cheongam-ro, Nam-gu, Pohang, Gyeongsangbuk-do, 37673, Republic of Korea
| | - Yoon Huh
- Analysis and Assessment Research Center, Research Institute of Industrial Science and Technology (RIST), 67 Cheongam-ro, Nam-gu, Pohang, Gyeongsangbuk-do, 37673, Republic of Korea
| | - Jaekyung Hyun
- School of Pharmacy, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do, 16419, Republic of Korea
| | - Jong Min Yuk
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
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2
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DiCecco LA, Gao R, Gray JL, Kelly DF, Sone ED, Grandfield K. Liquid Transmission Electron Microscopy for Probing Collagen Biomineralization. NANO LETTERS 2023; 23:9760-9768. [PMID: 37669509 DOI: 10.1021/acs.nanolett.3c02344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
Collagen biomineralization is fundamental to hard tissue assembly. While studied extensively, collagen mineralization processes are not fully understood, with the majority of theories derived from electron microscopy (EM) under static, dehydrated, or frozen conditions, unlike the liquid phase environment where mineralization occurs. Herein, novel liquid transmission EM (TEM) strategies are presented, in which collagen mineralization was explored in liquid for the first time via TEM. Custom thin-film enclosures were employed to visualize the mineralization of reconstituted collagen fibrils in a calcium phosphate and polyaspartic acid solution to promote intrafibrillar mineralization. TEM highlighted that at early time points precursor mineral particles attached to collagen and progressed to crystalline mineral platelets aligned with fibrils at later time points. This aligns with observations from other techniques and validates the liquid TEM approach. This work provides a new liquid imaging approach for exploring collagen biomineralization, advancing toward understanding disease pathogenesis and remineralization strategies for hard tissues.
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Affiliation(s)
- Liza-Anastasia DiCecco
- Department of Materials Science and Engineering, McMaster University, Hamilton, ON L8S 4L8, Canada
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802-4400, United States
| | - Ruixin Gao
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Jennifer L Gray
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Deborah F Kelly
- Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802-4400, United States
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for Structural Oncology, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Eli D Sone
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
- Department of Materials Science and Engineering, University of Toronto, Toronto, ON M5S 3E4, Canada
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1X3, Canada
| | - Kathryn Grandfield
- Department of Materials Science and Engineering, McMaster University, Hamilton, ON L8S 4L8, Canada
- School of Biomedical Engineering, McMaster University, Hamilton, ON L8S 4L8, Canada
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3
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Ma H, Kang S, Lee S, Park G, Bae Y, Park G, Kim J, Li S, Baek H, Kim H, Yu JS, Lee H, Park J, Yang J. Moisture-Induced Degradation of Quantum-Sized Semiconductor Nanocrystals through Amorphous Intermediates. ACS NANO 2023. [PMID: 37399231 DOI: 10.1021/acsnano.3c03103] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/05/2023]
Abstract
Elucidating the water-induced degradation mechanism of quantum-sized semiconductor nanocrystals is an important prerequisite for their practical application because they are vulnerable to moisture compared to their bulk counterparts. In-situ liquid-phase transmission electron microscopy is a desired method for studying nanocrystal degradation, and it has recently gained technical advancement. Herein, the moisture-induced degradation of semiconductor nanocrystals is investigated using graphene double-liquid-layer cells that can control the initiation of reactions. Crystalline and noncrystalline domains of quantum-sized CdS nanorods are clearly distinguished during their decomposition with atomic-scale imaging capability of the developed liquid cells. The results reveal that the decomposition process is mediated by the involvement of the amorphous-phase formation, which is different from conventional nanocrystal etching. The reaction can proceed without the electron beam, suggesting that the amorphous-phase-mediated decomposition is induced by water. Our study discloses unexplored aspects of moisture-induced deformation pathways of semiconductor nanocrystals, involving amorphous intermediates.
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Affiliation(s)
- Hyeonjong Ma
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Sungsu Kang
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering, and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Seunghan Lee
- Department of Physics, Konkuk University, Seoul 05029, Korea
| | - Gisang Park
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Yuna Bae
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering, and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Gyuri Park
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Jihoon Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering, and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Shi Li
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Hayeon Baek
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering, and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyeongseung Kim
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Jong-Sung Yu
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
- Energy Science and Engineering Research Center, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
| | - Hoonkyung Lee
- Department of Physics, Konkuk University, Seoul 05029, Korea
| | - Jungwon Park
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering, and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
- Institute of Engineering Research, College of Engineering, Seoul National University, Seoul 08826, Republic of Korea
- Advanced Institute of Convergence Technology, Seoul National University, Suwon-si, Gyeonggi-do 16229, Republic of Korea
| | - Jiwoong Yang
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
- Energy Science and Engineering Research Center, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, Republic of Korea
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4
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Jabbari V, Sawczyk M, Amiri A, Král P, Shahbazian-Yassar R. Unveiling growth and dynamics of liposomes by graphene liquid cell-transmission electron microscopy. NANOSCALE 2023; 15:5011-5022. [PMID: 36790028 DOI: 10.1039/d2nr06147c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Liposome is a model system for biotechnological and biomedical purposes spanning from targeted drug delivery to modern vaccine research. Yet, the growth mechanism of liposomes is largely unknown. In this work, the formation and evolution of phosphatidylcholine-based liposomes are studied in real-time by graphene liquid cell-transmission electron microscopy (GLC-TEM). We reveal important steps in the growth, fusion and denaturation of phosphatidylcholine (PC) liposomes. We show that initially complex lipid aggregates resembling micelles start to form. These aggregates randomly merge while capturing water and forming small proto-liposomes. The nanoscopic containers continue sucking water until their membrane becomes convex and free of redundant phospholipids, giving stabilized PC liposomes of different sizes. In the initial stage, proto-liposomes grow at a rate of 10-15 nm s-1, which is followed by their growth rate of 2-5 nm s-1, limited by the lipid availability in the solution. Molecular dynamics (MD) simulations are used to understand the structure of micellar clusters, their evolution, and merging. The liposomes are also found to fuse through lipid bilayers docking followed by the formation of a hemifusion diaphragm and fusion pore opening. The liposomes denaturation can be described by initial structural destabilization and deformation of the membrane followed by the leakage of the encapsulated liquid. This study offers new insights on the formation and growth of lipid-based molecular assemblies which is applicable to a wide range of amphiphilic molecules.
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Affiliation(s)
- Vahid Jabbari
- Mechanical and Industrial Engineering Department, University of Illinois at Chicago, Chicago, IL 60607, USA. rsyassar@uic
| | - Michal Sawczyk
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Azadeh Amiri
- Mechanical and Industrial Engineering Department, University of Illinois at Chicago, Chicago, IL 60607, USA. rsyassar@uic
| | - Petr Král
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, USA
- Department of Physics, Pharmaceutical Sciences, and Chemical Engineering, University of Illinois at Chicago, Chicago, USA
| | - Reza Shahbazian-Yassar
- Mechanical and Industrial Engineering Department, University of Illinois at Chicago, Chicago, IL 60607, USA. rsyassar@uic
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5
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Wang H, Xu Z, Mao S, Granick S. Experimental Guidelines to Image Transient Single-Molecule Events Using Graphene Liquid Cell Electron Microscopy. ACS NANO 2022; 16:18526-18537. [PMID: 36256532 DOI: 10.1021/acsnano.2c06766] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In quest of the holy grail to "see" how individual molecules interact in liquid environments, single-molecule imaging methods now include liquid-phase electron microscopy, whose resolution can be nanometers in space and several frames per second in time using an ordinary electron microscope that is routinely available to many researchers. However, with the current state of the art, protocols that sound similar to those described in the literature lead to outcomes that can differ. The key challenge is to achieve sample contrast under a safe electron dose within a frame rate adequate to capture the molecular process. Here, we present such examples from different systems─synthetic polymer, lipid assembly, DNA-enzyme─in which we have done this using graphene liquid cells. We describe detailed experimental procedures and share empirical experience for conducting successful experiments, starting from fabrication of a graphene liquid cell, to identification of high-quality liquid pockets from desirable shapes and sizes, to effective searching for target sample pockets under electron microscopy, and to discrimination of sample molecules and molecular processes of interest. These experimental tips can assist others who wish to make use of this method.
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Affiliation(s)
- Huan Wang
- College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China
- Beijing National Laboratory for Molecular Sciences, Center for Spectroscopy, Beijing Key Laboratory of Polymer Chemistry & Physics of Ministry of Education, Center for Soft Matter Science and Engineering, National Biomedical Imaging Center, Peking University, Beijing 100871, People's Republic of China
| | - Zhun Xu
- College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Sheng Mao
- Department of Mechanics and Engineering Sciences, College of Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Steve Granick
- Center for Soft and Living Matter, Institute for Basic Science, Ulsan, Korea, 44919
- Department of Chemistry and Physics, Ulsan National Institute of Science and Technology, Ulsan, Korea 44919
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6
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Kim JY, Lim H, Moon DW. Mass Spectrometry Imaging of Small Molecules from Live Cells and Tissues using Nanomaterials. SURF INTERFACE ANAL 2022. [DOI: 10.1002/sia.7070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jae Young Kim
- School of Electronic and Electrical Engineering, College of IT Engineering Kyungpook National University Daegu Republic of Korea
| | - Heejin Lim
- Department of New Biology Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu Republic of Korea
| | - Dae Won Moon
- Department of New Biology Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu Republic of Korea
- Dschool of Undergraduate Studies, DGIST Daegu Republic of Korea
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7
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Supramolecular systems chemistry through advanced analytical techniques. Anal Bioanal Chem 2022; 414:5105-5119. [DOI: 10.1007/s00216-021-03824-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/26/2021] [Accepted: 12/01/2021] [Indexed: 11/01/2022]
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8
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Guide to controlling the electron dose to improve low-dose imaging of sensitive samples. Micron 2021; 145:103058. [DOI: 10.1016/j.micron.2021.103058] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 03/14/2021] [Accepted: 03/14/2021] [Indexed: 11/22/2022]
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9
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Park J, Koo K, Noh N, Chang JH, Cheong JY, Dae KS, Park JS, Ji S, Kim ID, Yuk JM. Graphene Liquid Cell Electron Microscopy: Progress, Applications, and Perspectives. ACS NANO 2021; 15:288-308. [PMID: 33395264 DOI: 10.1021/acsnano.0c10229] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Graphene liquid cell electron microscopy (GLC-EM), a cutting-edge liquid-phase EM technique, has become a powerful tool to directly visualize wet biological samples and the microstructural dynamics of nanomaterials in liquids. GLC uses graphene sheets with a one carbon atom thickness as a viewing window and a liquid container. As a result, GLC facilitates atomic-scale observation while sustaining intact liquids inside an ultra-high-vacuum transmission electron microscopy chamber. Using GLC-EM, diverse scientific results have been recently reported in the material, colloidal, environmental, and life science fields. Here, the developments of GLC fabrications, such as first-generation veil-type cells, second-generation well-type cells, and third-generation liquid-flowing cells, are summarized. Moreover, recent GLC-EM studies on colloidal nanoparticles, battery electrodes, mineralization, and wet biological samples are also highlighted. Finally, the considerations and future opportunities associated with GLC-EM are discussed to offer broad understanding and insight on atomic-resolution imaging in liquid-state dynamics.
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Affiliation(s)
- Jungjae Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Kunmo Koo
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Namgyu Noh
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Joon Ha Chang
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Jun Young Cheong
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Kyun Seong Dae
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Ji Su Park
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Sanghyeon Ji
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Il-Doo Kim
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Jong Min Yuk
- Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
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10
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Supra-Molecular Assemblies of ORAI1 at Rest Precede Local Accumulation into Puncta after Activation. Int J Mol Sci 2021; 22:ijms22020799. [PMID: 33466866 PMCID: PMC7831003 DOI: 10.3390/ijms22020799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/04/2021] [Accepted: 01/12/2021] [Indexed: 12/13/2022] Open
Abstract
The Ca2+ selective channel ORAI1 and endoplasmic reticulum (ER)-resident STIM proteins form the core of the channel complex mediating store operated Ca2+ entry (SOCE). Using liquid phase electron microscopy (LPEM), the distribution of ORAI1 proteins was examined at rest and after SOCE-activation at nanoscale resolution. The analysis of over seven hundred thousand ORAI1 positions revealed a number of ORAI1 channels had formed STIM-independent distinct supra-molecular clusters. Upon SOCE activation and in the presence of STIM proteins, a fraction of ORAI1 assembled in micron-sized two-dimensional structures, such as the known puncta at the ER plasma membrane contact zones, but also in divergent structures such as strands, and ring-like shapes. Our results thus question the hypothesis that stochastically migrating single ORAI1 channels are trapped at regions containing activated STIM, and we propose instead that supra-molecular ORAI1 clusters fulfill an amplifying function for creating dense ORAI1 accumulations upon SOCE-activation.
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11
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EGFR Expression in HER2-Driven Breast Cancer Cells. Int J Mol Sci 2020; 21:ijms21239008. [PMID: 33260837 PMCID: PMC7729501 DOI: 10.3390/ijms21239008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/20/2020] [Accepted: 11/24/2020] [Indexed: 12/12/2022] Open
Abstract
The epidermal growth factor receptor HER2 is overexpressed in 20% of breast cancer cases. HER2 is an orphan receptor that is activated ligand-independently by homodimerization. In addition, HER2 is able to heterodimerize with EGFR, HER3, and HER4. Heterodimerization has been proposed as a mechanism of resistance to therapy for HER2 overexpressing breast cancer. Here, a method is presented for the simultaneous detection of individual EGFR and HER2 receptors in the plasma membrane of breast cancer cells via specific labeling with quantum dot nanoparticles (QDs). Correlative fluorescence microscopy and liquid phase electron microscopy were used to analyze the plasma membrane expression levels of both receptors in individual intact cells. Fluorescent single-cell analysis of SKBR3 breast cancer cells dual-labeled for EGFR and HER2 revealed a heterogeneous expression for receptors within both the cell population as well as within individual cells. Subsequent electron microscopy of individual cells allowed the determination of individual receptors label distributions. QD-labeled EGFR was observed with a surface density of (0.5–5) × 101 QDs/µm2, whereas labeled HER2 expression was higher ranging from (2–10) × 102 QDs/µm2. Although most SKBR3 cells expressed low levels of EGFR, an enrichment was observed at large plasma membrane protrusions, and amongst a newly discovered cellular subpopulation termed EGFR-enriched cells.
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12
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Noh N, Park J, Park JS, Koo K, Park JY, Yuk JM. Lithographically patterned well-type graphene liquid cells with rational designs. LAB ON A CHIP 2020; 20:2796-2803. [PMID: 32633750 DOI: 10.1039/d0lc00440e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Graphene liquid cell transmission electron microscopy allows in situ observation of nanomaterial dynamics in a liquid environment. However, this method suffers from both random formation and small size of liquid pockets. Here, we introduce facile and mass-producible graphene-sealed well-type liquid cells with rational designs. The developed liquid cell structure and its formation mechanism depending on hole diameter (d)/spacer thickness (h) ratio are systematically analyzed. Finally, we show its high-resolution imaging and chemical analysis capability for nanoparticles and biomaterial applications. This work will provide an enhanced liquid cell platform for diverse liquid environmental studies.
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Affiliation(s)
- Namgyu Noh
- Department of Materials Science & Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
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13
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Dahmke IN, Trampert P, Weinberg F, Mostajeran Z, Lautenschläger F, de Jonge N. Correlative Fluorescence- and Electron Microscopy of Whole Breast Cancer Cells Reveals Different Distribution of ErbB2 Dependent on Underlying Actin. Front Cell Dev Biol 2020; 8:521. [PMID: 32714928 PMCID: PMC7344305 DOI: 10.3389/fcell.2020.00521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 06/02/2020] [Indexed: 12/26/2022] Open
Abstract
Epidermal growth factor receptor 2 (ErbB2) is found overexpressed in several cancers, such as gastric, and breast cancer, and is, therefore, an important therapeutic target. ErbB2 plays a central role in cancer cell invasiveness, and is associated with cytoskeletal reorganization. In order to study the spatial correlation of single ErbB2 proteins and actin filaments, we applied correlative fluorescence microscopy (FM), and scanning transmission electron microscopy (STEM) to image specifically labeled SKBR3 breast cancer cells. The breast cancer cells were grown on microchips, transformed to express an actin-green fluorescent protein (GFP) fusion protein, and labeled with quantum dot (QD) nanoparticles attached to specific anti-ErbB2 Affibodies. FM was performed to identify cellular regions with spatially correlated actin and ErbB2 expression. For STEM of the intact plasma membrane of whole cells, the cells were fixed and covered with graphene. Spatial distribution patterns of ErbB2 in the actin rich ruffled membrane regions were examined, and compared to adjacent actin-low regions of the same cell, revealing an association of putative signaling active ErbB2 homodimers with actin-rich regions. ErbB2 homodimers were found absent from actin-low membrane regions, as well as after treatment of cells with Cytochalasin D, which breaks up larger actin filaments. In both latter data sets, a significant inter-label distance of 36 nm was identified, possibly indicating an indirect attachment to helical actin filaments via the formation of heterodimers of ErbB2 with epidermal growth factor receptor (EGFR). The possible attachment to actin filaments was further explored by identifying linear QD-chains in actin-rich regions, which also showed an inter-label distance of 36 nm.
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Affiliation(s)
| | - Patrick Trampert
- German Research Center for Artificial Intelligence, Saarbrücken, Germany
| | | | | | - Franziska Lautenschläger
- INM – Leibniz Institute for New Materials, Saarbrücken, Germany
- Department of Physics, Saarland University, Saarbrücken, Germany
| | - Niels de Jonge
- INM – Leibniz Institute for New Materials, Saarbrücken, Germany
- Department of Physics, Saarland University, Saarbrücken, Germany
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14
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Microscopic and nanoscopic protein imaging by SIMS and helium ion microscopy. Biointerphases 2020; 15:038501. [PMID: 32590901 DOI: 10.1116/6.0000220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Single protein imaging and understanding their interactions are of paramount importance to understand the life phenomena. Recently reported multiplex protein SIMS imaging methodology using metal-oxide nanoparticle conjugated antibodies can be extended to a single protein imaging methodology using He ion microscopy (HIM). It is proposed here that single protein can be imaged in the microscale and the nanoscale by the complementary use of SIMS and HIM.
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15
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Weinberg F, Han MKL, Dahmke IN, Del Campo A, de Jonge N. Anti-correlation of HER2 and focal adhesion complexes in the plasma membrane. PLoS One 2020; 15:e0234430. [PMID: 32511274 PMCID: PMC7279600 DOI: 10.1371/journal.pone.0234430] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 05/25/2020] [Indexed: 11/18/2022] Open
Abstract
Excess presence of the human epidermal growth factor receptor 2 (HER2) as well as of the focal adhesion protein complexes are associated with increased proliferation, migratory, and invasive behavior of cancer cells. A cross-regulation between HER2 and integrin signaling pathways has been found, but the exact mechanism remains elusive. Here, we investigated whether HER2 colocalizes with focal adhesion complexes on breast cancer cells overexpressing HER2. For this purpose, vinculin or talin green fluorescent protein (GFP) fusion proteins, both key constituents of focal adhesions, were expressed in breast cancer cells. HER2 was either extracellularly or intracellularly labeled with fluorescent quantum dots nanoparticles (QDs). The cell-substrate interface was analyzed at the location of the focal adhesions by means of total internal reflection fluorescent microscopy or correlative fluorescence- and scanning transmission electron microscopy. Expression of HER2 at the cell-substrate interface was only observed upon intracellular labeling, and was heterogeneous with both HER2-enriched and -low regions. In contrast to an expected enrichment of HER2 at focal adhesions, an anti-correlated expression pattern was observed for talin and HER2. Our findings suggest a spatial anti-correlation between HER2 and focal adhesion complexes for adherent cells.
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Affiliation(s)
| | | | | | - Aránzazu Del Campo
- INM – Leibniz Institute for New Materials, Saarbrücken, Germany
- Department of Chemistry, University of Saarland, Saarbrücken, Germany
| | - Niels de Jonge
- INM – Leibniz Institute for New Materials, Saarbrücken, Germany
- Department of Physics, University of Saarland, Saarbrücken, Germany
- * E-mail:
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16
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Wu H, Friedrich H, Patterson JP, Sommerdijk NAJM, de Jonge N. Liquid-Phase Electron Microscopy for Soft Matter Science and Biology. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2001582. [PMID: 32419161 DOI: 10.1002/adma.202001582] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/05/2020] [Accepted: 04/06/2020] [Indexed: 05/20/2023]
Abstract
Innovations in liquid-phase electron microscopy (LP-EM) have made it possible to perform experiments at the optimized conditions needed to examine soft matter. The main obstacle is conducting experiments in such a way that electron beam radiation can be used to obtain answers for scientific questions without changing the structure and (bio)chemical processes in the sample due to the influence of the radiation. By overcoming these experimental difficulties at least partially, LP-EM has evolved into a new microscopy method with nanometer spatial resolution and sub-second temporal resolution for analysis of soft matter in materials science and biology. Both experimental design and applications of LP-EM for soft matter materials science and biological research are reviewed, and a perspective of possible future directions is given.
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Affiliation(s)
- Hanglong Wu
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
| | - Heiner Friedrich
- Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
| | - Joseph P Patterson
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
| | - Nico A J M Sommerdijk
- Department of Biochemistry, Radboud University Medical Center, Nijmegen, 6500 HB, The Netherlands
| | - Niels de Jonge
- INM - Leibniz Institute for New Materials, Saarbrücken, 66123, Germany
- Department of Physics, Saarland University, Saarbrücken, 66123, Germany
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17
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Alansary D, Peckys DB, Niemeyer BA, de Jonge N. Detecting single ORAI1 proteins within the plasma membrane reveals higher-order channel complexes. J Cell Sci 2020; 133:jcs.240358. [PMID: 31822631 DOI: 10.1242/jcs.240358] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/02/2019] [Indexed: 12/22/2022] Open
Abstract
ORAI1 proteins form highly selective Ca2+ channels in the plasma membrane. Crystallographic data point towards a hexameric stoichiometry of ORAI1 channels, whereas optical methods postulated ORAI1 channels to reside as dimers at rest, and other data suggests that they have a tetrameric configuration. Here, liquid-phase scanning transmission electron microscopy (STEM) and quantum dot (QD) labeling was utilized to study the conformation of ORAI1 proteins at rest. To address the question of whether ORAI1 was present as a dimer, experiments were designed using single ORAI1 monomers and covalently linked ORAI1 dimers with either one or two label-binding positions. The microscopic data was statistically analyzed via the pair correlation function. Label pairs were found in all cases, even for concatenated dimers with one label-binding position, which is only possible if a significant fraction of ORAI1 was assembled in larger order oligomers than dimers, binding at least two QDs. This interpretation of the data was consistent with Blue Native PAGE analysis showing that ORAI1 is mainly present as a complex of an apparent molecular mass larger than that calculated for a dimer.
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Affiliation(s)
- Dalia Alansary
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Diana B Peckys
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Niels de Jonge
- INM - Leibniz Institute for New Materials, 66123 Saarbrücken, Germany .,Department of Physics, University of Saarland, 66123 Saarbrücken, Germany
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18
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Smith JW, Chen Q. Liquid-phase electron microscopy imaging of cellular and biomolecular systems. J Mater Chem B 2020; 8:8490-8506. [DOI: 10.1039/d0tb01300e] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Liquid-phase electron microscopy, a new method for real-time nanoscopic imaging in liquid, makes it possible to study cells or biomolecules with a singular combination of spatial and temporal resolution. We review the state of the art in biological research in this growing and promising field.
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Affiliation(s)
- John W. Smith
- Department of Materials Science and Engineering, University of Illinois at Urbana–Champaign
- Urbana
- USA
| | - Qian Chen
- Department of Materials Science and Engineering, University of Illinois at Urbana–Champaign
- Urbana
- USA
- Department of Chemistry
- University of Illinois at Urbana–Champaign
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19
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Pu S, Gong C, Robertson AW. Liquid cell transmission electron microscopy and its applications. ROYAL SOCIETY OPEN SCIENCE 2020; 7:191204. [PMID: 32218950 PMCID: PMC7029903 DOI: 10.1098/rsos.191204] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/19/2019] [Indexed: 06/10/2023]
Abstract
Transmission electron microscopy (TEM) has long been an essential tool for understanding the structure of materials. Over the past couple of decades, this venerable technique has undergone a number of revolutions, such as the development of aberration correction for atomic level imaging, the realization of cryogenic TEM for imaging biological specimens, and new instrumentation permitting the observation of dynamic systems in situ. Research in the latter has rapidly accelerated in recent years, based on a silicon-chip architecture that permits a versatile array of experiments to be performed under the high vacuum of the TEM. Of particular interest is using these silicon chips to enclose fluids safely inside the TEM, allowing us to observe liquid dynamics at the nanoscale. In situ imaging of liquid phase reactions under TEM can greatly enhance our understanding of fundamental processes in fields from electrochemistry to cell biology. Here, we review how in situ TEM experiments of liquids can be performed, with a particular focus on microchip-encapsulated liquid cell TEM. We will cover the basics of the technique, and its strengths and weaknesses with respect to related in situ TEM methods for characterizing liquid systems. We will show how this technique has provided unique insights into nanomaterial synthesis and manipulation, battery science and biological cells. A discussion on the main challenges of the technique, and potential means to mitigate and overcome them, will also be presented.
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20
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Improved ion imaging of slowly dried neurons and skin cells by graphene cover in time-of-flight secondary ion mass spectrometry. Biointerphases 2019; 14:051001. [PMID: 31529971 DOI: 10.1116/1.5118259] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a powerful tool to obtain both chemical information and spatial distribution of specific molecules of interest on a specimen surface. However, since the focused ion beam requires ultrahigh vacuum conditions for desorption and ionization of analytes, proper specimen preparation, such as drying, freeze-drying, and frozen dehydration, is required for ToF-SIMS analysis. In particular, biological specimens with high moisture content generally have a problem of specimen deformation during the normal drying process for a vacuum environment. In this study, the authors propose a cellular specimen preparation method to improve the ion imaging of cells by reducing the deformation of specimens in ToF-SIMS analysis. When the cells on the slide substrate are completely covered with single-layer graphene, the ToF-SIMS imaging is improved by reduced cell deformation due to slow drying. In addition, the graphene encapsulation also induces a reduction in the yield of secondary ions, thereby suppressing the background ion spectra generated by the unwanted organic residues on the substrate, resulting in the improvement of ToF-SIMS imaging. The authors also found that adding plasma treatment to this sample preparation can further improve ion imaging of cells. After cell dehydration is completed, the covered graphene layer can be peeled off by air-plasma treatment and the unwanted organic residues on the substrate can be removed due to plasma cleaning, thereby much improving ion imaging of cells.
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Lim H, Lee SY, Moon DW, Kim JY. Preparation of cellular samples using graphene cover and air-plasma treatment for time-of-flight secondary ion mass spectrometry imaging. RSC Adv 2019; 9:28432-28438. [PMID: 35529615 PMCID: PMC9071169 DOI: 10.1039/c9ra05205d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 09/06/2019] [Indexed: 11/21/2022] Open
Abstract
We report on sample preparation methods based on plasma treatment for an improvement of multiple molecular ion images of cellular membranes in the ToF-SIMS method. The air-plasma treatment of fixed cellular samples efficiently removed the organic residues of any solutions used during sample preparation and improved the quality of ToF-SIMS images due to the resulting clean surface. We also studied cell preparation methods that combine single-layer graphene covering with air-plasma treatment to achieve a synergistic effect that eliminates background spectra by organic impurities while minimizing morphological cell deformation in a vacuum environmental analysis. When the cellular sample on the glass substrate is completely covered with the single-layer graphene, the cells trapped between the graphene and the substrate can effectively reduce morphological deformation by slow-dehydration. After slow-dehydration of cells is completed inside the graphene-cover, the covered graphene layer can be peeled off by air-plasma treatment, and the unwanted organic residues on the surface of cells and substrate can also be removed by plasma cleaning, thereby much improving ion imaging of cells with the ToF-SIMS method. It is confirmed that the cell samples in which the graphene-cover was removed by air-plasma treatment maintained their morphology well in comparison with the rapid air-dried cells in atomic force microscopy (AFM) and ToF-SIMS images. Cell preparation methods that combine a single-layer graphene cover with air-plasma treatment for improvement of ToF-SIMS imaging.![]()
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Affiliation(s)
- Heejin Lim
- Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST) 333 Techno Jungang Daero, Hyeonpung-Eup, Dalseong-Gun Daegu 42988 Republic of Korea
| | - Sun Young Lee
- Division of Technology Business, National Institute for Nanomaterials Technology (NINT), Pohang University of Science and Technology (POSTECH) 77 Cheongam-Ro, Nam-Gu Pohang Gyeongbuk 37673 Republic of Korea
| | - Dae Won Moon
- Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST) 333 Techno Jungang Daero, Hyeonpung-Eup, Dalseong-Gun Daegu 42988 Republic of Korea
| | - Jae Young Kim
- Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST) 333 Techno Jungang Daero, Hyeonpung-Eup, Dalseong-Gun Daegu 42988 Republic of Korea .,Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST) 333 Techno Jungang Daero, Hyeonpung-Eup, Dalseong-Gun Daegu 42988 Republic of Korea
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22
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Peckys DB, Hirsch D, Gaiser T, de Jonge N. Visualisation of HER2 homodimers in single cells from HER2 overexpressing primary formalin fixed paraffin embedded tumour tissue. Mol Med 2019; 25:42. [PMID: 31455202 PMCID: PMC6712713 DOI: 10.1186/s10020-019-0108-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 07/31/2019] [Indexed: 12/11/2022] Open
Abstract
Background HER2 is considered as one of the most important, predictive biomarkers in oncology. The diagnosis of HER2 positive cancer types such as breast- and gastric cancer is usually based on immunohistochemical HER2 staining of tumour tissue. However, the current immunohistochemical methods do not provide localized information about HER2’s functional state. In order to generate signals leading to cell growth and proliferation, the receptor spontaneously forms homodimers, a process that can differ between individual cancer cells. Materials and methods HER2 overexpressing tumour cells were dissociated from formalin-fixed paraffin-embedded (FFPE) patient’s biopsy sections, subjected to a heat-induced antigen retrieval procedure, and immobilized on microchips. HER2 was specifically labelled via a two-step protocol involving the incubation with an Affibody-biotin compound followed by the binding of a streptavidin coated quantum dot (QD) nanoparticle. Cells with membrane bound HER2 were identified using fluorescence microscopy, coated with graphene to preserve their hydrated state, and subsequently examined by scanning transmission electron microscopy (STEM) to obtain the locations at the single molecule level. Label position data was statistically analysed via the pair correlation function, yielding information about the presence of HER2 homodimers. Results Tumour cells from two biopsies, scored HER2 3+, and a HER2 negative control sample were examined. The specific labelling protocol was first tested for a sectioned tissue sample of HER2-overexpressing tumour. Subsequently, a protocol was optimized to study HER2 homodimerization in single cells dissociated from the tissue section. Electron microscopy data showed membrane bound HER2 in average densities of 201–689 proteins/μm2. An automated, statistical analysis of well over 200,000 of measured protein positions revealed the presence of HER2 homodimers in 33 and 55% of the analysed images for patient 1 and 2, respectively. Conclusions We introduced an electron microscopy method capable of measuring the positions of individually labelled HER2 proteins in patient tumour cells from which information about the functional status of the receptor was derived. This method could take HER2 testing a step further by examining HER2 homodimerization directly out of tumour tissue and may become important for adjusting a personalized antibody-based drug therapy. Electronic supplementary material The online version of this article (10.1186/s10020-019-0108-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Diana B Peckys
- Department of Biophysics, Saarland University, Homburg, Germany
| | - Daniela Hirsch
- Institute for Pathology, University Medical Center Mannheim, Ruprecht-Karls University of Heidelberg, Mannheim, Germany
| | - Timo Gaiser
- Institute for Pathology, University Medical Center Mannheim, Ruprecht-Karls University of Heidelberg, Mannheim, Germany
| | - Niels de Jonge
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany. .,Department of Physics, Saarland University, Saarbrücken, Germany.
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23
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Chen S, Wang J, Xin B, Yang Y, Ma Y, Zhou Y, Yuan L, Huang Z, Yuan Q. Direct Observation of Nanoparticles within Cells at Subcellular Levels by Super-Resolution Fluorescence Imaging. Anal Chem 2019; 91:5747-5752. [PMID: 30938156 DOI: 10.1021/acs.analchem.8b05919] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Direct observation of nanoparticles with high spatial resolution at subcellular levels is of great importance to understand the nanotoxicology and promote the biomedical applications of nanoparticles. Super-resolution fluorescence microscopy can break the diffraction resolution limit to achieve spatial resolution of tens of nanometers, making it ideal for highly accurate observation of nanoparticles in the cellular world. In this study, we introduced the employment of super-resolution fluorescence imaging for monitoring nanoparticles within cells. Carbocyanine dyes Alexa Flour 647 labeled mesoporous silica nanoparticles (designated as MSNs-AF647) were constructed as the super-resolution imaging nanoplatform in this work as proof of concept. The MSNs-AF647 were incubated with Hela cells, and the nanoparticles within cells were further monitored by super-resolution fluorescence microscopy. The fluorescence images of MSNs-AF647 within cells captured with the super-resolution fluorescence microscopy showed a much higher spatial resolution than that obtained using conventional fluorescence microscopy, showing that super-resolution fluorescence images can provide more accurate information to locate the nanoparticles at the subcellular levels. Moreover, other functional molecules can be easily loaded into the MSNs-AF647 super-resolution imaging nanoplatform, which suggested that super-resolution fluorescence imaging can further be applied to various bioimaging-related areas, such as imaging-guided therapy, with the aid of the MSNs-AF647 nanoplatform. This study demonstrates that super-resolution fluorescence microscopy offers a highly accurate method to study nanoparticles in the cellular world. We anticipate this strategy may further be applied to research areas such as studying the nanotoxicology and optimization of nanoparticle-based bioprobes or drugs by designing new nanostructured materials with multifunctional properties based on MSNs-AF647.
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Affiliation(s)
- Shasha Chen
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
| | - Jie Wang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
| | - Bo Xin
- Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430074 , PR China
| | - Yanbing Yang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
| | - Yurou Ma
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
| | - Yu Zhou
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
| | - Liangjie Yuan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
| | - Zhenli Huang
- Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430074 , PR China
| | - Quan Yuan
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , PR China
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24
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Yang J, Choi MK, Sheng Y, Jung J, Bustillo K, Chen T, Lee SW, Ercius P, Kim JH, Warner JH, Chan EM, Zheng H. MoS 2 Liquid Cell Electron Microscopy Through Clean and Fast Polymer-Free MoS 2 Transfer. NANO LETTERS 2019; 19:1788-1795. [PMID: 30741548 DOI: 10.1021/acs.nanolett.8b04821] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Two dimensional (2D) materials have found various applications because of their unique physical properties. For example, graphene has been used as the electron transparent membrane for liquid cell transmission electron microscopy (TEM) due to its high mechanical strength and flexibility, single-atom thickness, chemical inertness, etc. Here, we report using 2D MoS2 as a functional substrate as well as the membrane window for liquid cell TEM, which is enabled by our facile and polymer-free MoS2 transfer process. This provides the opportunity to investigate the growth of Pt nanocrystals on MoS2 substrates, which elucidates the formation mechanisms of such heterostructured 2D materials. We find that Pt nanocrystals formed in MoS2 liquid cells have a strong tendency to align their crystal lattice with that of MoS2, suggesting a van der Waals epitaxial relationship. Importantly, we can study its impact on the kinetics of the nanocrystal formation. The development of MoS2 liquid cells will allow further study of various liquid phenomena on MoS2, and the polymer-free MoS2 transfer process will be implemented in a wide range of applications.
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Affiliation(s)
- Jiwoong Yang
- Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Moon Kee Choi
- Department of Bioengineering and Tsinghua Berkeley Shenzhen Institute , University of California , Berkeley , California 94720 , United States
- Biological Systems and Engineering Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Yuewen Sheng
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Jaebong Jung
- School of Mechanical Engineering , Pusan National University , Busan 46241 , South Korea
| | - Karen Bustillo
- The Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Tongxin Chen
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Seung-Wuk Lee
- Department of Bioengineering and Tsinghua Berkeley Shenzhen Institute , University of California , Berkeley , California 94720 , United States
- Biological Systems and Engineering Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Peter Ercius
- The Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Ji Hoon Kim
- School of Mechanical Engineering , Pusan National University , Busan 46241 , South Korea
| | - Jamie H Warner
- Department of Materials , University of Oxford , 16 Parks Road , Oxford OX1 3PH , United Kingdom
| | - Emory M Chan
- The Molecular Foundry , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Haimei Zheng
- Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
- Department of Materials Science and Engineering , University of California , Berkeley , California 94720 , United States
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25
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He K, Shokuhfar T, Shahbazian-Yassar R. Imaging of soft materials using in situ liquid-cell transmission electron microscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:103001. [PMID: 30524096 DOI: 10.1088/1361-648x/aaf616] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This review summarizes the breakthroughs in the field of soft material characterization by in situ liquid-cell transmission electron microscopy (TEM). The focus of this review is mostly on soft biological species such as cells, bacteria, viruses, proteins and polymers. The comparison between the two main liquid-cell systems (silicon nitride membranes liquid cell and graphene liquid cell) is also discussed in terms of their spatial resolution and imaging/analytical capabilities. We have showcased how liquid-cell TEM can reveal the structural details of whole cells, enable the chemical probing of proteins, detect the structural conformation of viruses, and monitor the dynamics of polymerization. In addition, the challenges faced by decoupling electron beam effect on beam-sensitive soft materials are discussed. At the end, future perspectives of in situ liquid-cell TEM studies of soft materials are outlined.
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Affiliation(s)
- Kun He
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL 60607, United States of America
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26
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Keskin S, de Jonge N. Reduced Radiation Damage in Transmission Electron Microscopy of Proteins in Graphene Liquid Cells. NANO LETTERS 2018; 18:7435-7440. [PMID: 30431282 DOI: 10.1021/acs.nanolett.8b02490] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Liquid-phase electron microscopy (LPEM) is capable of imaging native (unstained) protein structure in liquid, but the achievable spatial resolution is limited by radiation damage. This damaging effect is more pronounced when targeting small molecular features than for larger structures. The matter is even more complicated because the critical dose that a sample can endure before radiation damage not only varies between proteins but also critically depends on the experimental conditions. Here, we examined the effect of the electron beam on the observed protein structure for optimized conditions using a liquid sample enclosure assembled from graphene sheets. It has been shown that graphene can reduce the damaging effect of electrons on biological materials. We used radiation sensitive microtubule proteins and investigated the radiation damage on these structures as a function of the spatial frequencies of the observed features with transmission electron microscopy (TEM). Microtubule samples were also examined using cryo-electron microscopy (cryo-TEM) for comparison. We used an electron flux of 11 ± 1-16 ± 1 e-/Å2s and obtained a series of images from the same sample region. Our results show that graphene-encapsulated microtubules can maintain their structural features of spatial frequencies of up to 0.20 nm-1 (5 nm), reflecting protofilaments for electron densities of up to 7.2 ± 1.4 × 102 e-/Å2, an order of magnitude higher than measured for frozen microtubules in amorphous ice.
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Affiliation(s)
- Sercan Keskin
- Leibniz Institute for New Materials (INM) , Saarbrücken D-66123 , Germany
| | - Niels de Jonge
- Leibniz Institute for New Materials (INM) , Saarbrücken D-66123 , Germany
- Department of Physics , Saarland University , Saarbrücken D-66123 , Germany
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27
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Hutzler A, Schmutzler T, Jank MPM, Branscheid R, Unruh T, Spiecker E, Frey L. Unravelling the Mechanisms of Gold-Silver Core-Shell Nanostructure Formation by in Situ TEM Using an Advanced Liquid Cell Design. NANO LETTERS 2018; 18:7222-7229. [PMID: 30346790 DOI: 10.1021/acs.nanolett.8b03388] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The growth of silver shells on gold nanorods is investigated by in situ liquid cell transmission electron microscopy using an advanced liquid cell architecture. The design is based on microwells in which the liquid is confined between a thin Si3N4 membrane on one side and a few-layer graphene cap on the other side. A well-defined specimen thickness and an ultraflat cell top allow for the application of high-resolution TEM and the application of analytical TEM techniques on the same sample. The combination of high-resolution data with chemical information is validated by radically new insights into the growth of silver shells on cetrimonium bromide stabilized gold nanorods. It is shown that silver bromide particles already formed in the stock solution play an important role in the exchange of silver ions. The Ag shell growth can be directly correlated with the layer-by-layer dissolution of AgBr nanocrystals, which can be controlled by the electron flux density via distinctly generated chemical species in the solvent. The derived model framework is confirmed by in situ UV-vis absorption spectroscopy evaluating the blue shift in the longitudinal surface plasmon resonance of anisotropic NRs in a complementary batch experiment.
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Affiliation(s)
- Andreas Hutzler
- Electron Devices (LEB), Department of Electrical, Electronic and Communication Engineering , Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Cauerstraße 6 , 91058 Erlangen , Germany
| | - Tilo Schmutzler
- Institute for Crystallography and Structural Physics (ICSP), Department of Physics , Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Staudtstraße 3 , 91058 Erlangen , Germany
| | - Michael P M Jank
- Fraunhofer Institute for Integrated Systems and Device Technology IISB , Schottkystraße 10 , 91058 Erlangen , Germany
| | - Robert Branscheid
- Institute of Micro- and Nanostructure Research (IMN) and Center for Nanoanalysis and Electron Microscopy (CENEM), Department of Materials Science and Engineering , Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Cauerstraße 6 , 91058 Erlangen , Germany
| | - Tobias Unruh
- Institute for Crystallography and Structural Physics (ICSP), Department of Physics , Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Staudtstraße 3 , 91058 Erlangen , Germany
| | - Erdmann Spiecker
- Institute of Micro- and Nanostructure Research (IMN) and Center for Nanoanalysis and Electron Microscopy (CENEM), Department of Materials Science and Engineering , Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Cauerstraße 6 , 91058 Erlangen , Germany
| | - Lothar Frey
- Electron Devices (LEB), Department of Electrical, Electronic and Communication Engineering , Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Cauerstraße 6 , 91058 Erlangen , Germany
- Fraunhofer Institute for Integrated Systems and Device Technology IISB , Schottkystraße 10 , 91058 Erlangen , Germany
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28
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Ando T, Bhamidimarri SP, Brending N, Colin-York H, Collinson L, De Jonge N, de Pablo PJ, Debroye E, Eggeling C, Franck C, Fritzsche M, Gerritsen H, Giepmans BNG, Grunewald K, Hofkens J, Hoogenboom JP, Janssen KPF, Kaufman R, Klumpermann J, Kurniawan N, Kusch J, Liv N, Parekh V, Peckys DB, Rehfeldt F, Reutens DC, Roeffaers MBJ, Salditt T, Schaap IAT, Schwarz US, Verkade P, Vogel MW, Wagner R, Winterhalter M, Yuan H, Zifarelli G. The 2018 correlative microscopy techniques roadmap. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2018; 51:443001. [PMID: 30799880 PMCID: PMC6372154 DOI: 10.1088/1361-6463/aad055] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 06/14/2018] [Accepted: 07/01/2018] [Indexed: 05/19/2023]
Abstract
Developments in microscopy have been instrumental to progress in the life sciences, and many new techniques have been introduced and led to new discoveries throughout the last century. A wide and diverse range of methodologies is now available, including electron microscopy, atomic force microscopy, magnetic resonance imaging, small-angle x-ray scattering and multiple super-resolution fluorescence techniques, and each of these methods provides valuable read-outs to meet the demands set by the samples under study. Yet, the investigation of cell development requires a multi-parametric approach to address both the structure and spatio-temporal organization of organelles, and also the transduction of chemical signals and forces involved in cell-cell interactions. Although the microscopy technologies for observing each of these characteristics are well developed, none of them can offer read-out of all characteristics simultaneously, which limits the information content of a measurement. For example, while electron microscopy is able to disclose the structural layout of cells and the macromolecular arrangement of proteins, it cannot directly follow dynamics in living cells. The latter can be achieved with fluorescence microscopy which, however, requires labelling and lacks spatial resolution. A remedy is to combine and correlate different readouts from the same specimen, which opens new avenues to understand structure-function relations in biomedical research. At the same time, such correlative approaches pose new challenges concerning sample preparation, instrument stability, region of interest retrieval, and data analysis. Because the field of correlative microscopy is relatively young, the capabilities of the various approaches have yet to be fully explored, and uncertainties remain when considering the best choice of strategy and workflow for the correlative experiment. With this in mind, the Journal of Physics D: Applied Physics presents a special roadmap on the correlative microscopy techniques, giving a comprehensive overview from various leading scientists in this field, via a collection of multiple short viewpoints.
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Affiliation(s)
- Toshio Ando
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Japan
| | | | | | - H Colin-York
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom
| | | | - Niels De Jonge
- INM-Leibniz Institute for New Materials, 66123 Saarbrücken, Germany
- Saarland University, 66123 Saarbrücken, Germany
| | - P J de Pablo
- Dpto. Física de la Materia Condensada Universidad Autónoma de Madrid 28049, Madrid, Spain
- Instituto de Física de la Materia Condensada IFIMAC, Universidad Autónoma de Madrid 28049, Madrid, Spain
| | - Elke Debroye
- KU Leuven, Department of Chemistry, B-3001 Heverlee, Belgium
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom
- Institute of Applied Optics, Friedrich-Schiller University, Jena, Germany
- Leibniz Institute of Photonic Technology (IPHT), Jena, Germany
| | - Christian Franck
- Department of Mechanical Engineering, University of Wisconsin-Madison, 1513 University Ave, Madison, WI 53706, United States of America
| | - Marco Fritzsche
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom
- Kennedy Institute for Rheumatology, University of Oxford, Oxford, United Kingdom
| | - Hans Gerritsen
- Debye Institute, Utrecht University, Utrecht, Netherlands
| | - Ben N G Giepmans
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Kay Grunewald
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Centre of Structural Systems Biology Hamburg and University of Hamburg, Hamburg, Germany
- Heinrich-Pette-Institute, Leibniz Institute of Virology, Hamburg, Germany
| | - Johan Hofkens
- KU Leuven, Department of Chemistry, B-3001 Heverlee, Belgium
| | | | | | - Rainer Kaufman
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Centre of Structural Systems Biology Hamburg and University of Hamburg, Hamburg, Germany
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Judith Klumpermann
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584CX Utrecht, Netherlands
| | - Nyoman Kurniawan
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - Nalan Liv
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Heidelberglaan 100, 3584CX Utrecht, Netherlands
| | - Viha Parekh
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Diana B Peckys
- Faculty of Medicine, Saarland University, 66421 Homburg, Germany
| | - Florian Rehfeldt
- University of Göttingen, Third Institute of Physics-Biophysics, 37077 Göttingen, Germany
| | - David C Reutens
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | - Tim Salditt
- University of Göttingen, Institute for X-Ray Physics, 37077 Göttingen, Germany
| | - Iwan A T Schaap
- SmarAct GmbH, Schütte-Lanz-Str. 9, D-26135 Oldenburg, Germany
| | - Ulrich S Schwarz
- Institute for Theoretical Physics and BioQuant, Heidelberg University, Heidelberg, Germany
| | - Paul Verkade
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Michael W Vogel
- Centre for Advanced Imaging, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Richard Wagner
- Department of Life Sciences & Chemistry, Jacobs University, Bremen, Germany
| | | | - Haifeng Yuan
- KU Leuven, Department of Chemistry, B-3001 Heverlee, Belgium
| | - Giovanni Zifarelli
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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Yang J, Alam SB, Yu L, Chan E, Zheng H. Dynamic behavior of nanoscale liquids in graphene liquid cells revealed by in situ transmission electron microscopy. Micron 2018; 116:22-29. [PMID: 30265880 DOI: 10.1016/j.micron.2018.09.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/10/2018] [Accepted: 09/14/2018] [Indexed: 12/24/2022]
Abstract
Recent advances in graphene liquid cells for in situ transmission electron microscopy (TEM) have opened many opportunities for the study of materials transformations and chemical reactions in liquids with high spatial resolution. However, the behavior of thin liquids encapsulated in a graphene liquid cell has not been fully understood. Here, we report real time TEM imaging of the nanoscale dynamic behavior of liquids in graphene nanocapillaries. Our observations reveal that the interfaces between liquid and gas bubble can fluctuate, leading to the generation of liquid nanodroplets near the interfaces. Liquid nanodroplets often show irregular shape with dynamic changes of their configuration under the electron beam. We consider that the dynamic motion of liquid-gas interfaces might be introduced by the electrostatic energy from transiently charged interfaces. We find that improving the wettability of graphene liquid cells by ultraviolet-ozone treatment can significantly modify the dynamic motion of the encapsulated liquids. Our study provides valuable information of the interactions between liquid and graphene under the electron beam, and it also offers key insights on the nanoscale fluid dynamics in confined spaces.
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Affiliation(s)
- Jiwoong Yang
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Sardar B Alam
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Lei Yu
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States; Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, United States
| | - Emory Chan
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Haimei Zheng
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States; Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, United States.
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30
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Linear Chains of HER2 Receptors Found in the Plasma Membrane Using Liquid-Phase Electron Microscopy. Biophys J 2018; 115:503-513. [PMID: 30099989 DOI: 10.1016/j.bpj.2018.06.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/27/2018] [Accepted: 06/12/2018] [Indexed: 02/06/2023] Open
Abstract
The spatial distribution of the human epidermal growth factor 2 (HER2) receptor in the plasma membrane of SKBR3 and HCC1954 breast cancer cells was studied. The receptor was labeled with quantum dot nanoparticles, and fixed whole cells were imaged in their native liquid state with environmental scanning electron microscopy using scanning transmission electron microscopy detection. The locations of individual HER2 positions were determined in a total plasma membrane area of 991 μm2 for several SKBR3 cells and 1062 μm2 for HCC1954 cells. Some of the HER2 receptors were arranged in a linear chain with interlabel distances of 40 ± 7 and 32 ± 10 nm in SKBR3 and HCC1954 cells, respectively. The finding was tested against randomly occurring linear chains of six or more positions, from which it was concluded that the experimental finding is significant and did not arise from random label distributions. Because the measured interlabel distance in the HER2 chains is similar to the 36-nm helix-repetition distance of actin filaments, it is proposed that a linking mechanism between HER2 and actin filaments leads to linearly aligned oligomers.
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31
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Textor M, de Jonge N. Strategies for Preparing Graphene Liquid Cells for Transmission Electron Microscopy. NANO LETTERS 2018; 18:3313-3321. [PMID: 29799208 DOI: 10.1021/acs.nanolett.8b01366] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A graphene liquid cell for transmission electron microscopy (TEM) uses one or two graphene sheets to separate the liquid from the vacuum in the microscope. In principle, graphene is an excellent material for such an application because it allows the highest possible spatial resolution, provides a flexible covering foil, and effectively protects the liquid from evaporating. Examples in open literature have demonstrated atomic-resolution TEM using small liquid pockets and the coverage of whole biological cells with graphene sheets. A total of three different basic types of liquid cells are discerned: (i) one graphene sheet is used to cover a liquid sample supported by a thin membrane of another material (for example, silicon nitride, SiN), (ii) two graphene sheets pressed together leaving liquid pockets with graphene at both sides, and (iii) a spacer material with liquid pockets covered at both sides by graphene. A total of four different process flows are available for liquid cell assembly, but there is not yet a consensus on the best routes, and a number of variations exist. The key step is the transfer of graphene to a liquid sample, which is complicated by practical issues that arise from imperfections in the graphene sheets, such as cracks. This review provides an overview of these different approaches to assembling graphene liquid cells and discusses the main obstacles and ideas to overcome them with the prospect of developing the nanoscale technology needed for graphene liquid cells so that they become available on a routine basis for electron microscopy in liquid. It also provides guidance in selecting the appropriate type of graphene liquid cell and the best assembly method for a specific experiment.
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Affiliation(s)
- Martin Textor
- INM, Leibniz Institute for New Materials , D-66123 Saarbrücken , Germany
| | - Niels de Jonge
- INM, Leibniz Institute for New Materials , D-66123 Saarbrücken , Germany
- Department of Physics , Saarland University , D-66123 Saarbrücken , Germany
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32
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Hauwiller MR, Ondry JC, Alivisatos AP. Using Graphene Liquid Cell Transmission Electron Microscopy to Study in Situ Nanocrystal Etching. J Vis Exp 2018:57665. [PMID: 29863683 PMCID: PMC6101270 DOI: 10.3791/57665] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Graphene liquid cell electron microscopy provides the ability to observe nanoscale chemical transformations and dynamics as the reactions are occurring in liquid environments. This manuscript describes the process for making graphene liquid cells through the example of graphene liquid cell transmission electron microscopy (TEM) experiments of gold nanocrystal etching. The protocol for making graphene liquid cells involves coating gold, holey-carbon TEM grids with chemical vapor deposition graphene and then using those graphene-coated grids to encapsulate liquid between two graphene surfaces. These pockets of liquid, with the nanomaterial of interest, are imaged in the electron microscope to see the dynamics of the nanoscale process, in this case the oxidative etching of gold nanorods. By controlling the electron beam dose rate, which modulates the etching species in the liquid cell, the underlying mechanisms of how atoms are removed from nanocrystals to form different facets and shapes can be better understood. Graphene liquid cell TEM has the advantages of high spatial resolution, compatibility with traditional TEM holders, and low start-up costs for research groups. Current limitations include delicate sample preparation, lack of flow capability, and reliance on electron beam-generated radiolysis products to induce reactions. With further development and control, graphene liquid cell may become a ubiquitous technique in nanomaterials and biology, and is already being used to study mechanisms governing growth, etching, and self-assembly processes of nanomaterials in liquid on the single particle level.
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Affiliation(s)
| | - Justin C Ondry
- Department of Chemistry, University of California-Berkeley
| | - A Paul Alivisatos
- Department of Chemistry, University of California-Berkeley; Department of Material Science and Engineering, University of California-Berkeley; Kavli Energy NanoScience Institute; Materials Sciences Division, Lawrence Berkeley National Laboratory;
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