1
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Su S, Zhao J, Ly TH. Scanning Probe Microscopies for Characterizations of 2D Materials. SMALL METHODS 2024:e2400211. [PMID: 38766949 DOI: 10.1002/smtd.202400211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/12/2024] [Indexed: 05/22/2024]
Abstract
2D materials are intriguing due to their remarkably thin and flat structure. This unique configuration allows the majority of their constituent atoms to be accessible on the surface, facilitating easier electron tunneling while generating weak surface forces. To decipher the subtle signals inherent in these materials, the application of techniques that offer atomic resolution (horizontal) and sub-Angstrom (z-height vertical) sensitivity is crucial. Scanning probe microscopy (SPM) emerges as the quintessential tool in this regard, owing to its atomic-level spatial precision, ability to detect unitary charges, responsiveness to pico-newton-scale forces, and capability to discern pico-ampere currents. Furthermore, the versatility of SPM to operate under varying environmental conditions, such as different temperatures and in the presence of various gases or liquids, opens up the possibility of studying the stability and reactivity of 2D materials in situ. The characteristic flatness, surface accessibility, ultra-thinness, and weak signal strengths of 2D materials align perfectly with the capabilities of SPM technologies, enabling researchers to uncover the nuanced behaviors and properties of these advanced materials at the nanoscale and even the atomic scale.
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Affiliation(s)
- Shaoqiang Su
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, 999077, China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, 999077, P. R. China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, 518057, China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, 999077, China
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, 518057, China
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2
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Tarábková H, Janda P. Effect of Graphite Aging on Its Wetting Properties and Surface Blocking by Gaseous Nanodomains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:14154-14161. [PMID: 37734043 PMCID: PMC10552534 DOI: 10.1021/acs.langmuir.3c02151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/11/2023] [Indexed: 09/23/2023]
Abstract
Early works considered basal planes of highly ordered pyrolytic graphite (HOPG) as hydrophobic, relatively inert materials with low electrocatalytic activity due to nonpolar sp2 carbon. On the contrary, a freshly prepared HOPG surface exhibits intrinsically mildly hydrophilic properties, with a low contact angle of water, which increases after exposure to an ambient atmosphere. This process, called aging, ascribed to adsorption of airborne hydrocarbons, is reportedly accompanied by strong decay of electron transfer kinetics, the mechanism of which is not yet fully understood. Examining both freshly prepared and aged basal plane HOPG immersed in water by PeakForce quantitative nanomechanical imaging, we have found that aged HOPG is occupied by ambient gaseous nanodomains, the existence of which is explained by incomplete wetting. They cover up to 60% of the immersed surface and their incidence is in direct relation with graphite aging time. In contrast with aged graphite, gaseous nanodomains were absent on the freshly stripped HOPG surface. It can be concluded that ambient gaseous nanodomains can prevent aged basal plane HOPG from contact with aqueous media and may thus affect processes at the solid-liquid interface.
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Affiliation(s)
- Hana Tarábková
- Department of Electrochemical
Materials, J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, CZ-182 23 Prague 8, Czech Republic
| | - Pavel Janda
- Department of Electrochemical
Materials, J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, CZ-182 23 Prague 8, Czech Republic
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3
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Burgo TL, Pereira GKR, Iglesias BA, Moreira KS, Valandro LF. AFM advanced modes for dental and biomedical applications. J Mech Behav Biomed Mater 2022; 136:105475. [PMID: 36195052 DOI: 10.1016/j.jmbbm.2022.105475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/15/2022] [Accepted: 09/18/2022] [Indexed: 11/18/2022]
Abstract
Several analytical methods have been employed to elucidate bonding mechanisms between dental hard tissues, luting agents and restorative materials. Atomic Force Microscopy (AFM) imaging that has been extensively used in materials science, but its full capabilities are poorly explored by dental research community. In fact, commonly used to obtain topographic images of different surfaces, it turns out that AFM is an underestimated technique considering that there are dozens of basic and advanced modes that are scarcely used to explain properties of biomaterials. Thus, this paper addresses the use of phase-contrast imaging, force-distance curves, nanomechanical and Kelvin probe force techniques during AFM analysis to explore topological, nanomechanical and electrical properties of Y-TZP samples modified by different surface treatments, which has been widely used to promote adhesive enhancements to such substrate. The AFM methods are capable of access erstwhile inaccessible properties of Y-TZP which allowed us to describe its adhesive properties correctly. Thus, AFM technique emerges as a key tool to investigate the complex nature of biomaterials and highlighting its inherent interdisciplinarity that can be successfully used for bridging fragmented disciplines such as solid-state physics, microbiology and dental sciences.
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Affiliation(s)
- ThiagoA L Burgo
- Department of Chemistry and Environmental Sciences, Ibilce, São Paulo State University (Unesp), São Jose do Rio Preto, São Paulo State, Brazil.
| | - Gabriel Kalil Rocha Pereira
- MSciD and Ph.D. Post-Graduate Program in Oral Science, Faculty of Dentistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
| | - Bernardo Almeida Iglesias
- Department of Chemistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
| | - Kelly S Moreira
- Department of Chemistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
| | - Luiz Felipe Valandro
- MSciD and Ph.D. Post-Graduate Program in Oral Science, Faculty of Dentistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
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4
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Puppulin L, Kanayama D, Terasaka N, Sakai K, Kodera N, Umeda K, Sumino A, Marchesi A, Weilin W, Tanaka H, Fukuma T, Suga H, Matsumoto K, Shibata M. Macrocyclic Peptide-Conjugated Tip for Fast and Selective Molecular Recognition Imaging by High-Speed Atomic Force Microscopy. ACS APPLIED MATERIALS & INTERFACES 2021; 13:54817-54829. [PMID: 34766499 DOI: 10.1021/acsami.1c17708] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Fast and selective recognition of molecules at the nanometer scale without labeling is a much desired but still challenging goal to achieve. Here, we show the use of high-speed atomic force microscopy (HS-AFM) for real-time and real-space recognition of unlabeled membrane receptors using tips conjugated with small synthetic macrocyclic peptides. The single-molecule recognition method is validated by experiments on the human hepatocyte growth factor receptor (hMET), which selectively binds to the macrocyclic peptide aMD4. By testing and comparing aMD4 synthesized with linkers of different lengths and rigidities, we maximize the interaction between the functionalized tip and hMET added to both a mica surface and supported lipid bilayers. Phase contrast imaging by HS-AFM enables us to discriminate nonlabeled hMET against the murine MET homologue, which does not bind to aMD4. Moreover, using ligands and linkers of small size, we achieve minimal deterioration of the spatial resolution in simultaneous topographic imaging. The versatility of macrocyclic peptides in detecting unlimited types of membrane receptors with high selectivity and the fast imaging by HS-AFM broaden the range of future applications of this method for molecular recognition without labeling.
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Affiliation(s)
- Leonardo Puppulin
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
- Department of Pathology and Cell Regulation, Graduate School of Medical Sciences, Kyoto Prefectural University of Medicine, Kajii-cho, Kawaramachi-Hirokoji, Kyoto 602-8566, Japan
| | - Daiki Kanayama
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Naohiro Terasaka
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Katsuya Sakai
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
- Division of Tumor Dynamics and Regulation, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Noriyuki Kodera
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Kenichi Umeda
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Ayumi Sumino
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Arin Marchesi
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Wei Weilin
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Hideo Tanaka
- Department of Pathology and Cell Regulation, Graduate School of Medical Sciences, Kyoto Prefectural University of Medicine, Kajii-cho, Kawaramachi-Hirokoji, Kyoto 602-8566, Japan
| | - Takeshi Fukuma
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Kunio Matsumoto
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
- Division of Tumor Dynamics and Regulation, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Mikihiro Shibata
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
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5
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Zajki-Zechmeister K, Kaira GS, Eibinger M, Seelich K, Nidetzky B. Processive Enzymes Kept on a Leash: How Cellulase Activity in Multienzyme Complexes Directs Nanoscale Deconstruction of Cellulose. ACS Catal 2021; 11:13530-13542. [PMID: 34777910 PMCID: PMC8576811 DOI: 10.1021/acscatal.1c03465] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/11/2021] [Indexed: 12/15/2022]
Abstract
Biological deconstruction of polymer materials gains efficiency from the spatiotemporally coordinated action of enzymes with synergetic function in polymer chain depolymerization. To perpetuate enzyme synergy on a solid substrate undergoing deconstruction, the overall attack must alternate between focusing the individual enzymes locally and dissipating them again to other surface sites. Natural cellulases working as multienzyme complexes assembled on a scaffold protein (the cellulosome) maximize the effect of local concentration yet restrain the dispersion of individual enzymes. Here, with evidence from real-time atomic force microscopy to track nanoscale deconstruction of single cellulose fibers, we show that the cellulosome forces the fiber degradation into the transversal direction, to produce smaller fragments from multiple local attacks ("cuts"). Noncomplexed enzymes, as in fungal cellulases or obtained by dissociating the cellulosome, release the confining force so that fiber degradation proceeds laterally, observed as directed ablation of surface fibrils and leading to whole fiber "thinning". Processive cellulases that are enabled to freely disperse evoke the lateral degradation and determine its efficiency. Our results suggest that among natural cellulases, the dispersed enzymes are more generally and globally effective in depolymerization, while the cellulosome represents a specialized, fiber-fragmenting machinery.
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Affiliation(s)
- Krisztina Zajki-Zechmeister
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, 8010 Graz, Austria
| | - Gaurav Singh Kaira
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, 8010 Graz, Austria
- Austrian
Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria
| | - Manuel Eibinger
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, 8010 Graz, Austria
| | - Klara Seelich
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, 8010 Graz, Austria
| | - Bernd Nidetzky
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 10-12/1, 8010 Graz, Austria
- Austrian
Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria
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6
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Rajabifar B, Bajaj A, Reifenberger R, Proksch R, Raman A. Discrimination of adhesion and viscoelasticity from nanoscale maps of polymer surfaces using bimodal atomic force microscopy. NANOSCALE 2021; 13:17428-17441. [PMID: 34647552 DOI: 10.1039/d1nr03437e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The simultaneous excitation and measurement of two eigenmodes in bimodal atomic force microscopy (AFM) during sub-micron scale surface imaging augments the number of observables at each pixel of the image compared to the normal tapping mode. However, a comprehensive connection between the bimodal AFM observables and the surface adhesive and viscoelastic properties of polymer samples remains elusive. To address this gap, we first propose an algorithm that systematically accommodates surface forces and linearly viscoelastic three-dimensional deformation computed via Attard's model into the bimodal AFM framework. The proposed algorithm simultaneously satisfies the amplitude reduction formulas for both resonant eigenmodes and enables the rigorous prediction and interpretation of bimodal AFM observables with a first-principles approach. We used the proposed algorithm to predict the dependence of bimodal AFM observables on local adhesion and standard linear solid (SLS) constitutive parameters as well as operating conditions. Secondly, we present an inverse method to quantitatively predict the local adhesion and SLS viscoelastic parameters from bimodal AFM data acquired on a heterogeneous sample. We demonstrate the method experimentally using bimodal AFM on polystyrene-low density polyethylene (PS-LDPE) polymer blend. This inverse method enables the quantitative discrimination of adhesion and viscoelastic properties from bimodal AFM maps of such samples and opens the door for advanced computational interaction models to be used to quantify local nanomechanical properties of adhesive, viscoelastic materials using bimodal AFM.
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Affiliation(s)
- Bahram Rajabifar
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907, USA.
- Birck Nanotechnology Center, 1205 W State Street, West Lafayette, IN 47907, USA
| | - Anil Bajaj
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907, USA.
| | - Ronald Reifenberger
- Birck Nanotechnology Center, 1205 W State Street, West Lafayette, IN 47907, USA
| | - Roger Proksch
- Asylum Research, an Oxford Instruments company, Santa Barbara, CA, 93117, USA
| | - Arvind Raman
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907, USA.
- Birck Nanotechnology Center, 1205 W State Street, West Lafayette, IN 47907, USA
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7
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Nam S, Khim D, Martinez GT, Varambhia A, Nellist PD, Kim Y, Anthopoulos TD, Bradley DDC. Significant Performance Improvement in n-Channel Organic Field-Effect Transistors with C 60 :C 70 Co-Crystals Induced by Poly(2-ethyl-2-oxazoline) Nanodots. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2100421. [PMID: 34165833 DOI: 10.1002/adma.202100421] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 04/20/2021] [Indexed: 06/13/2023]
Abstract
Solution-processed organic field-effect transistors (OFETs) have attracted great interest due to their potential as logic devices for bendable and flexible electronics. In relation to n-channel structures, soluble fullerene semiconductors have been widely studied. However, they have not yet met the essential requirements for commercialization, primarily because of low charge carrier mobility, immature large-scale fabrication processes, and insufficient long-term operational stability. Interfacial engineering of the carrier-injecting source/drain (S/D) electrodes has been proposed as an effective approach to improve charge injection, leading also to overall improved device characteristics. Here, it is demonstrated that a non-conjugated neutral dipolar polymer, poly(2-ethyl-2-oxazoline) (PEOz), formed as a nanodot structure on the S/D electrodes, enhances electron mobility in n-channel OFETs using a range of soluble fullerenes. Overall performance is especially notable for (C60 -Ih )[5,6]fullerene (C60 ) and (C70 -D5h(6) )[5,6]fullerene (C70 ) blend films, with an increase from 0.1 to 2.1 cm2 V-1 s-1 . The high relative mobility and eighteen-fold improvement are attributed not only to the anticipated reduction in S/D electrode work function but also to the beneficial effects of PEOz on the formation of a face-centered-cubic C60 :C70 co-crystal structure within the blend films.
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Affiliation(s)
- Sungho Nam
- Department of Physics, University of Oxford, Oxford, OX1 3PD, UK
| | - Dongyoon Khim
- Blackett Laboratory, Department of Physics and Centre for Plastic Electronics, Imperial College London, London, SW7 2BW, UK
| | | | - Aakash Varambhia
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - Peter D Nellist
- Department of Materials, University of Oxford, Oxford, OX1 3PH, UK
| | - Youngkyoo Kim
- Organic Nanoelectronics Laboratory and KNU Institute for Nanophotonics Applications (KINPA), School of Applied Chemical Engineering, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Thomas D Anthopoulos
- Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Donal D C Bradley
- Department of Physics, University of Oxford, Oxford, OX1 3PD, UK
- Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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8
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Farokh Payam A, Biglarbeigi P, Morelli A, Lemoine P, McLaughlin J, Finlay D. Data acquisition and imaging using wavelet transform: a new path for high speed transient force microscopy. NANOSCALE ADVANCES 2021; 3:383-398. [PMID: 36131753 PMCID: PMC9417248 DOI: 10.1039/d0na00531b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 09/10/2020] [Indexed: 06/13/2023]
Abstract
The unique ability of Atomic Force Microscopy (AFM) to image, manipulate and characterize materials at the nanoscale has made it a remarkable tool in nanotechnology. In dynamic AFM, acquisition and processing of the photodetector signal originating from probe-sample interaction is a critical step in data analysis and measurements. However, details of such interaction including its nonlinearity and dynamics of the sample surface are limited due to the ultimately bounded bandwidth and limited time scales of data processing electronics of standard AFM. Similarly, transient details of the AFM probe's cantilever signal are lost due to averaging of data by techniques which correlate the frequency spectrum of the captured data with a temporally invariant physical system. Here, we introduce a fundamentally new approach for dynamic AFM data acquisition and imaging based on applying the wavelet transform on the data stream from the photodetector. This approach provides the opportunity for exploration of the transient response of the cantilever, analysis and imaging of the dynamics of amplitude and phase of the signals captured from the photodetector. Furthermore, it can be used for the control of AFM which would yield increased imaging speed. Hence the proposed method opens a pathway for high-speed transient force microscopy.
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Affiliation(s)
- Amir Farokh Payam
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering, Ulster University Jordanstown Shore Road Northern Ireland BT37 0QB UK
| | - Pardis Biglarbeigi
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering, Ulster University Jordanstown Shore Road Northern Ireland BT37 0QB UK
| | - Alessio Morelli
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering, Ulster University Jordanstown Shore Road Northern Ireland BT37 0QB UK
| | - Patrick Lemoine
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering, Ulster University Jordanstown Shore Road Northern Ireland BT37 0QB UK
| | - James McLaughlin
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering, Ulster University Jordanstown Shore Road Northern Ireland BT37 0QB UK
| | - Dewar Finlay
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering, Ulster University Jordanstown Shore Road Northern Ireland BT37 0QB UK
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9
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Garcia R. Nanomechanical mapping of soft materials with the atomic force microscope: methods, theory and applications. Chem Soc Rev 2020; 49:5850-5884. [PMID: 32662499 DOI: 10.1039/d0cs00318b] [Citation(s) in RCA: 161] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Fast, high-resolution, non-destructive and quantitative characterization methods are needed to develop materials with tailored properties at the nanoscale or to understand the relationship between mechanical properties and cell physiology. This review introduces the state-of-the-art force microscope-based methods to map at high-spatial resolution the elastic and viscoelastic properties of soft materials. The experimental methods are explained in terms of the theories that enable the transformation of observables into material properties. Several applications in materials science, molecular biology and mechanobiology illustrate the scope, impact and potential of nanomechanical mapping methods.
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Affiliation(s)
- Ricardo Garcia
- Instituto de Ciencia de Materiales de Madrid, CSIC, c/Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain.
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10
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An R, Qiu X, Shah FU, Riehemann K, Fuchs H. Controlling the nanoscale friction by layered ionic liquid films. Phys Chem Chem Phys 2020; 22:14941-14952. [PMID: 32588010 DOI: 10.1039/d0cp02146f] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The nanofriction coefficient of ionic liquids (ILs), 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) and 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]), on the surfaces of mica and graphite was investigated using atomic force microscopy (AFM). A pronounced layered spatial distribution was found in the IL film formed on the solid substrates and can be divided into 3 well distinguishable regions exhibiting different physical properties with increasing distance from the substrate. We found that the friction coefficient (μ) increases monotonically as the layering thickness decreases, no matter what the thickness of the bulk IL is. This suggests that the layering assembled IL at solid surfaces is more important than the bulk phase in determining the magnitude of the nanoscale friction. The increase in the friction coefficient as the layering thickness decreases is most likely attributed to the assembled ordered IL layers closer to the substrate surfaces having a greater activation barrier for unlocking the surfaces to allow shear.
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Affiliation(s)
- Rong An
- Herbert Gleiter Institute of Nanoscience, Department of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China. and Center for Nanotechnology (CeNTech), Institute of Physics, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Xiuhua Qiu
- Herbert Gleiter Institute of Nanoscience, Department of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
| | - Faiz Ullah Shah
- Chemistry of Interfaces, Luleå University of Technology, SE 971 87 Luleå, Sweden
| | - Kristina Riehemann
- Center for Nanotechnology (CeNTech), Institute of Physics, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Harald Fuchs
- Herbert Gleiter Institute of Nanoscience, Department of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China. and Center for Nanotechnology (CeNTech), Institute of Physics, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
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11
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Caballero-Quintana I, Amargós-Reyes O, Maldonado JL, Nicasio-Collazo J, Romero-Borja D, Barreiro-Argüelles D, Molnár G, Bousseksou A. Scanning Probe Microscopy Analysis of Nonfullerene Organic Solar Cells. ACS APPLIED MATERIALS & INTERFACES 2020; 12:29520-29527. [PMID: 32466653 DOI: 10.1021/acsami.0c06048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, scanning probe microscopies (SPMs) are used for the analysis of PBDB-T, ITIC, and PBDB-T:ITIC layers of solar cells (OSCs). Scanning tunneling microscopy (STM) images of PBDB-T reveal that thin films (<1 nm) tend to form worm-like pattern (amorphous type) domains with an average chain-to-chain distance of 950 pm; likewise, STM images of ITIC show that side arms form chain-like patterns. STM images of PBDB-T:ITIC blend suggest why PBDB-T domains could facilitate charge dissociation. Further, a strong interchain π-π interaction of the ITIC molecules could promote self-organization, and under the mutual interaction with the PBDB-T polymer, it could influence the pathway formation for electron transport. Moreover, when correlating electrostatic force microscopy (EFM) and photoconductive atomic force microscopy (pc-AFM), the blend morphology and its electrical/electronic properties are determined; the ideal domain size of PBDB-T:ITIC blend phases for maximizing the generated photocurrent is 15-35 nm. Furthermore, phase contrast and surface electric potential characteristics with Kelvin probe force microscopy (KPFM) are measured to examine additional details about the surface and potential changes due to the domain differences in the active layer. OSCs based on the nonfullerene PBDB-T:ITIC active layer reach an average power conversion efficiency (PCE) of 9.1% (best 9.2%).
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Affiliation(s)
- Irving Caballero-Quintana
- Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica, A.P. 1-948, 37150 León, Guanajuato, México
| | - Olivia Amargós-Reyes
- Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica, A.P. 1-948, 37150 León, Guanajuato, México
| | - José-Luis Maldonado
- Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica, A.P. 1-948, 37150 León, Guanajuato, México
| | - Juan Nicasio-Collazo
- Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica, A.P. 1-948, 37150 León, Guanajuato, México
| | - Daniel Romero-Borja
- Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica, A.P. 1-948, 37150 León, Guanajuato, México
| | - Denisse Barreiro-Argüelles
- Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica, A.P. 1-948, 37150 León, Guanajuato, México
- Laboratorio de Fisicoquı́mica y Reactividad de Superficies (LaFReS), Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México (UNAM), CU, Coyoacán, 04510, Ciudad de México, México
| | - Gábor Molnár
- LCC, CNRS & University of Toulouse, 205 Route de Narbonne, BP44099, 31077 Toulouse Cedex 4, France
| | - Azzedine Bousseksou
- LCC, CNRS & University of Toulouse, 205 Route de Narbonne, BP44099, 31077 Toulouse Cedex 4, France
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12
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Suthiwanich K, Hiraguchi Y, Nyu T, Mondarte EAQ, Takai M, Hayashi T. Imaging the Nanophase-separated Structure of Block Copolymer Thin Film by Atomic Force Microscopy in Aqueous Solution. CHEM LETT 2020. [DOI: 10.1246/cl.190894] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Kasinan Suthiwanich
- Department of Materials Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan
| | - Yukari Hiraguchi
- Department of Bioengineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takashi Nyu
- Department of Materials Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan
| | - Evan Angelo Quimada Mondarte
- Department of Materials Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan
| | - Madoka Takai
- Department of Bioengineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tomohiro Hayashi
- Department of Materials Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8502, Japan
- Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- JST-PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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13
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An R, Wu M, Li J, Qiu X, Shah FU, Li J. On the ionic liquid films 'pinned' by core-shell structured Fe 3O 4@carbon nanoparticles and their tribological properties. Phys Chem Chem Phys 2019; 21:26387-26398. [PMID: 31793566 DOI: 10.1039/c9cp05905a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A strongly 'pinned' ionic liquid (IL, [BMIM][PF6]) film on a silicon (Si) surface via carbon capsuled Fe3O4 core-shell (Fe3O4@C) nanoparticles is achieved, revealing excellent friction-reducing ability at a high load. The adhesion force is measured to be ∼198 nN at the Fe3O4@C-Si interface by the Fe3O4@C colloidal AFM tip, which is stronger than that at both Fe3O4@C-Fe3O4@C (∼60 nN) and IL-Si (∼10 nN) interfaces, indicating a strong 'normal pin-force' towards the Si substrate. The resulting strengthened force enables the formation of lateral IL networks via the dipole-dipole attractions among Fe3O4 cores. The observed blue shift of the characteristic band related to the IL anion in the ATR-FTIR spectra confirmed the enhanced interaction. The N-Si, P-O chemical bonds formed as a result of the IL interactions with the Si substrate confirmed by XPS spectroscopy suggested that the IL lay on the Si plane. This orientation is favorable for Fe3O4@C nanoparticles to exert 'normal pin-force' and press the IL film strongly onto surfaces. The IL ions/clusters are thus anchored by these Fe3O4@C 'pins' onto the substrate to form a dense film, resulting in a smaller interaction size parameter, which is responsible for the reduced friction coefficient μ.
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Affiliation(s)
- Rong An
- Herbert Gleiter Institute of Nanoscience, Department of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
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14
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Zhou J, Sekatskii S, Welc R, Dietler G, Gruszecki WI. The role of xanthophylls in the supramolecular organization of the photosynthetic complex LHCII in lipid membranes studied by high-resolution imaging and nanospectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1861:148117. [PMID: 31734197 DOI: 10.1016/j.bbabio.2019.148117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/17/2019] [Accepted: 11/08/2019] [Indexed: 12/01/2022]
Abstract
The xanthophyll cycle is a regulatory mechanism operating in the photosynthetic apparatus of plants. It consists of the conversion of the xanthophyll pigment violaxanthin to zeaxanthin, and vice versa, in response to light intensity. According to the current understanding, one of the modes of regulatory activity of the cycle is associated with the influence on a molecular organization of pigment-protein complexes. In the present work, we analyzed the effect of violaxanthin and zeaxanthin on the molecular organization of the LHCII complex, in the environment of membranes formed with chloroplast lipids. Nanoscale imaging based on atomic force microscopy (AFM) showed that the presence of exogenous xanthophylls promotes the formation of the protein supramolecular structures. Nanoscale infrared (IR) absorption analysis based on AFM-IR nanospectroscopy suggests that zeaxanthin promotes the formation of LHCII supramolecular structures by forming inter-molecular β-structures. Meanwhile, the molecules of violaxanthin act as "molecular spacers" preventing self-aggregation of the protein, potentially leading to uncontrolled dissipation of excitation energy in the complex. This latter mechanism was demonstrated with the application of fluorescence lifetime imaging microscopy. The intensity-averaged chlorophyll a fluorescence lifetime determined in the LHCII samples without exogenous xanthophylls at the level of 0.72 ns was longer in the samples containing exogenous violaxanthin (2.14 ns), but shorter under the presence of zeaxanthin (0.49 ns) thus suggesting a role of this xanthophyll in promotion of the formation of structures characterized by effective excitation quenching. This mechanism can be considered as a representation of the overall photoprotective activity of the xanthophyll cycle.
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Affiliation(s)
- Jiangtao Zhou
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Sergey Sekatskii
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Renata Welc
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, 20-031 Lublin, Poland
| | - Giovanni Dietler
- Laboratory of Physics of Living Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Wieslaw I Gruszecki
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, 20-031 Lublin, Poland.
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15
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Enhancing phase contrast for bimodal AFM imaging in low quality factor environments. Ultramicroscopy 2019; 204:18-26. [DOI: 10.1016/j.ultramic.2019.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 03/23/2019] [Accepted: 05/12/2019] [Indexed: 11/20/2022]
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16
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Jiang Y, Pryse KM, Singamaneni S, Genin GM, Elson EL. Atomic force microscopy of phase separation on ruptured, giant unilamellar vesicles, and a mechanical pathway for the co-existence of lipid gel phases. J Biomech Eng 2019; 141:2735310. [PMID: 31141589 PMCID: PMC6611346 DOI: 10.1115/1.4043871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 05/26/2019] [Indexed: 11/08/2022]
Abstract
Giant unilamellar vesicles (GUVs) and supported lipid bilayers (SLBs) are synthetic model systems widely used in biophysical studies of lipid membranes. Although SLBs are advantageous for biophysical analysis, phase separation behaviors of lipid species in these two model systems can differ due to the lipid-substrate interactions that are present only for SLBs. In the present study, we report that in binary systems, certain phase domains on GUVs retain their original shapes and patterns after the GUVs rupture on glass surfaces. This enabled atomic force microscopy (AFM) experiments on phase domains, a procedure difficult to perform and interpret when applied to GUVs. Unusual phase behavior was evident in binary GUVs containing DLPC and either DPPC or DSPC. These DLPC/DSPC and DLPC/DPPC GUVs both presented the thermodynamic anomaly of having two co-existing gel phases. One phase (a bright phase) included a relatively high concentration of DiI-C20 but excluded Bodipy-HPC, and the other (dark phase) excluded both probes. The bright phases are of interest because they seem to stabilize dark phases against coalescence. Results suggested that the gel phases labeled by DiIC20 in the DLPC/DSPC membrane, which surround the dark gel phase, is an extra layer of membrane, indicating a highly curved structure that might stabilize the interior dark domains, thereby enabling the co-existence of two different gel phases. Results show the utility of AFM on collapsed GUVs, and suggest a possible mechanism for stabilization of lipid domains.
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Affiliation(s)
- Yanfei Jiang
- Department of Biochemistry and
Molecular Biophysics,
School of Medicine,
Washington University,
St. Louis, MO 63110
| | - Kenneth M. Pryse
- Department of Mechanical Engineering
and Materials Science,
Washington University,
St. Louis, MO 63110
| | - Srikanth Singamaneni
- Department of Mechanical Engineering
and Materials Science,
Washington University,
St. Louis, MO 63110
| | - Guy M. Genin
- Department of Mechanical Engineeringand Materials Science,
Washington University,
St. Louis, MO 63110
- NSF Science and Technology,Center for Engineering Mechanobiology,
Washington University,
St. Louis, MO 63110
e-mail:
| | - Elliot L. Elson
- Department of Biochemistry and
Molecular Biophysics,
School of Medicine,
Washington University,
St. Louis, MO 63110
e-mail:
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17
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Rajabifar B, Jadhav JM, Kiracofe D, Meyers GF, Raman A. Dynamic AFM on Viscoelastic Polymer Samples with Surface Forces. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01485] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Bahram Rajabifar
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology
Center, 1205 W. State Street, West Lafayette, Indiana 47907, United States
| | - Jyoti M. Jadhav
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology
Center, 1205 W. State Street, West Lafayette, Indiana 47907, United States
| | - Daniel Kiracofe
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology
Center, 1205 W. State Street, West Lafayette, Indiana 47907, United States
| | - Gregory F. Meyers
- Analytical Sciences, The Dow Chemical Company, 1897 Building, Midland, Michigan 48667, United States
| | - Arvind Raman
- School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, Indiana 47907, United States
- Birck Nanotechnology
Center, 1205 W. State Street, West Lafayette, Indiana 47907, United States
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18
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Mapping heterogeneity of cellular mechanics by multi-harmonic atomic force microscopy. Nat Protoc 2018; 13:2200-2216. [DOI: 10.1038/s41596-018-0031-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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19
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López-Guerra EA, Banfi F, Solares SD, Ferrini G. Theory of Single-Impact Atomic Force Spectroscopy in liquids with material contrast. Sci Rep 2018; 8:7534. [PMID: 29760518 PMCID: PMC5951954 DOI: 10.1038/s41598-018-25828-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 04/25/2018] [Indexed: 11/09/2022] Open
Abstract
Scanning probe microscopy has enabled nanoscale mapping of mechanical properties in important technological materials, such as tissues, biomaterials, polymers, nanointerfaces of composite materials, to name only a few. To improve and widen the measurement of nanoscale mechanical properties, a number of methods have been proposed to overcome the widely used force-displacement mode, that is inherently slow and limited to a quasi-static regime, mainly using multiple sinusoidal excitations of the sample base or of the cantilever. Here, a different approach is put forward. It exploits the unique capabilities of the wavelet transform analysis to harness the information encoded in a short duration spectroscopy experiment. It is based on an impulsive excitation of the cantilever and a single impact of the tip with the sample. It performs well in highly damped environments, which are often seen as problematic in other standard dynamic methods. Our results are very promising in terms of viscoelastic property discrimination. Their potential is oriented (but not limited) to samples that demand imaging in liquid native environments and also to highly vulnerable samples whose compositional mapping cannot be obtained through standard tapping imaging techniques.
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Affiliation(s)
- Enrique A López-Guerra
- Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC, 20052, USA
| | - Francesco Banfi
- Interdisciplinary Laboratories for Advanced Materials Physics, Università Cattolica del Sacro Cuore, I-25121, Brescia, Italy.,Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, I-25121, Brescia, Italy
| | - Santiago D Solares
- Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC, 20052, USA
| | - Gabriele Ferrini
- Interdisciplinary Laboratories for Advanced Materials Physics, Università Cattolica del Sacro Cuore, I-25121, Brescia, Italy. .,Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, I-25121, Brescia, Italy.
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20
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Atomic force phase imaging for dynamic detection of adsorbed hydrogen on a catalytic palladium surface under liquid. Ultramicroscopy 2017; 181:42-49. [PMID: 28486171 DOI: 10.1016/j.ultramic.2017.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/30/2017] [Accepted: 04/28/2017] [Indexed: 11/21/2022]
Abstract
Dynamic observation of hydrogen on catalytic metal surfaces is a challenging aspect of studying liquid-phase heterogeneous catalysis. Current methods suffer from one or more of the following limitations: the requirement to observe the surface in high vacuum, the inability to provide nanometer-level spatial resolution, the inability to deal with opaque catalysts and/or liquid immersion phase, the lack of real-time scanning of the surface area, and the inability to assess pronounced topographies or mixed materials. Atomic force microscopy (AFM) phase-shift imaging remedies these issues and provides an opportunity for dynamic direct observation of catalyst surfaces at or near actual reaction conditions immersed in liquid. Hydrogen was delivered to a palladium surface immersed in water by diffusion through a support film of dense polycarbonate. The palladium surface was continuously probed by tapping-mode AFM. The theoretically predicted time-dependent appearance of hydrogen on the water-covered palladium surface matched the experimental observation reasonably well. The technique demonstrated here is unique in that the appearance of hydrogen is dynamically detected in real time on a catalyst surface immersed in water with nanometer-scale spatial resolution. The results presented here supply a new level of information for heterogeneous catalysis that is not available with existing techniques. This work opens new avenues in the study of heterogeneous catalysis, a field with tremendous practical importance and serious analytical challenges.
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21
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Payam AF, Trewby W, Voïtchovsky K. Simultaneous viscosity and density measurement of small volumes of liquids using a vibrating microcantilever. Analyst 2017; 142:1492-1498. [PMID: 28352874 PMCID: PMC5450008 DOI: 10.1039/c6an02674e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Accepted: 03/18/2017] [Indexed: 11/21/2022]
Abstract
Many industrial and technological applications require precise determination of the viscosity and density of liquids. Such measurements can be time consuming and often require sampling substantial amounts of the liquid. These problems can partly be overcome with the use of microcantilevers but most existing methods depend on the specific geometry and properties of the cantilever, which renders simple, accurate measurement difficult. Here we present a new approach able to simultaneously quantify both the density and the viscosity of microliters of liquids. The method, based solely on the measurement of two characteristic frequencies of an immersed microcantilever, is completely independent of the choice of a cantilever. We derive analytical expressions for the liquid's density and viscosity and validate our approach with several simple liquids and different cantilevers. Application of our model to non-Newtonian fluids shows that the calculated viscosities are remarkably robust when compared to measurements obtained from a standard rheometer. However, the results become increasingly dependent on the cantilever geometry as the frequency-dependent nature of the liquid's viscosity becomes more significant.
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Affiliation(s)
- A. F. Payam
- Department of Physics , Durham University , Durham , UK .
| | - W. Trewby
- Department of Physics , Durham University , Durham , UK .
| | - K. Voïtchovsky
- Department of Physics , Durham University , Durham , UK .
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22
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Ricci M, Quinlan RA, Voïtchovsky K. Sub-nanometre mapping of the aquaporin-water interface using multifrequency atomic force microscopy. SOFT MATTER 2016; 13:187-195. [PMID: 27373564 DOI: 10.1039/c6sm00751a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Aquaporins are integral membrane proteins that regulate the transport of water and small molecules in and out of the cell. In eye lens tissue, circulation of water, ions and metabolites is ensured by a microcirculation system in which aquaporin-0 (AQP0) plays a central role. AQP0 allows water to flow beyond the diffusion limit through lens membranes. AQP0 naturally arranges in a square lattice. The malfunction of AQP0 is related to numerous diseases such as cataracts. Despite considerable research into its structure, function and dynamics, the interface between the protein and the surrounding liquid and the effect of the lattice arrangement on the behaviour of water at the interface with the membrane are still not fully understood. Here we use a multifrequency atomic force microscopy (AFM) approach to map both the liquid at the interface with AQP0 and the protein itself with sub-nanometer resolution. Imaging using the fundamental eigenmode of the AFM cantilever probes mainly the interfacial water at the surface of the membrane. The results highlight a well-defined region that surrounds AQP0 tetramers and where water exhibits a higher affinity for the protein. Imaging in the second eigenmode is dominated by the mechanical response of the protein and provides sub-molecular details of the protein surface and the sub-surface structure. The relationship between modes and harmonics is also examined.
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Affiliation(s)
- Maria Ricci
- Biological and Soft Systems, Cavendish Laboratory, Cambridge University, Cambridge, UK
| | - Roy A Quinlan
- School of Biological and Biomedical Sciences, Durham University, Durham, UK.
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23
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Multifrequency Force Microscopy of Helical Protein Assembly on a Virus. Sci Rep 2016; 6:21899. [PMID: 26915629 PMCID: PMC4768132 DOI: 10.1038/srep21899] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 02/01/2016] [Indexed: 01/09/2023] Open
Abstract
High-resolution microscopy techniques have been extensively used to investigate the structure of soft, biological matter at the nanoscale, from very thin membranes to small objects, like viruses. Electron microscopy techniques allow for obtaining extraordinary resolution by averaging signals from multiple identical structures. In contrast, atomic force microscopy (AFM) collects data from single entities. Here, it is possible to finely modulate the interaction with the samples, in order to be sensitive to their top surface, avoiding mechanical deformations. However, most biological surfaces are highly curved, such as fibers or tubes, and ultimate details of their surface are in the vicinity of steep height variations. This limits lateral resolution, even when sharp probes are used. We overcome this problem by using multifrequency force microscopy on a textbook example, the Tobacco Mosaic Virus (TMV). We achieved unprecedented resolution in local maps of amplitude and phase shift of the second excited mode, recorded together with sample topography. Our data, which combine multifrequency imaging and Fourier analysis, confirm the structure deduced from averaging techniques (XRD, cryoEM) for surface features of single virus particles, down to the helical pitch of the coat protein subunits, 2.3 nm. Remarkably, multifrequency AFM images do not require any image postprocessing.
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24
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Gao X, Campbell WA, Chaibva M, Jain P, Leslie AE, Frey SL, Legleiter J. Cholesterol Modifies Huntingtin Binding to, Disruption of, and Aggregation on Lipid Membranes. Biochemistry 2015; 55:92-102. [PMID: 26652744 DOI: 10.1021/acs.biochem.5b00900] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Huntington's disease (HD) is an inherited neurodegenerative disease caused by abnormally long CAG-repeats in the huntingtin gene that encode an expanded polyglutamine (polyQ) domain near the N-terminus of the huntingtin (htt) protein. Expanded polyQ domains are directly correlated to disease-related htt aggregation. Htt is found highly associated with a variety of cellular and subcellular membranes that are predominantly comprised of lipids. Since cholesterol homeostasis is altered in HD, we investigated how varying cholesterol content modifies the interactions between htt and lipid membranes. A combination of Langmuir trough monolayer techniques, vesicle permeability and binding assays, and in situ atomic force microscopy were used to directly monitor the interaction of a model, synthetic htt peptide and a full-length htt-exon1 recombinant protein with model membranes comprised of total brain lipid extract (TBLE) and varying amounts of exogenously added cholesterol. As the cholesterol content of the membrane increased, the extent of htt insertion decreased. Vesicles containing extra cholesterol were resistant to htt-induced permeabilization. Morphological and mechanical changes in the bilayer associated with exposure to htt were also drastically altered by the presence of cholesterol. Disrupted regions of pure TBLE bilayers were grainy in appearance and associated with a large number of globular aggregates. In contrast, morphological changes induced by htt in bilayers enriched in cholesterol were plateau-like with a smooth appearance. Collectively, these observations suggest that the presence and amount of cholesterol in lipid membranes play a critical role in htt binding and aggregation on lipid membranes.
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Affiliation(s)
- Xiang Gao
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26505, United States
| | - Warren A Campbell
- Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States
| | - Maxmore Chaibva
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26505, United States
| | - Pranav Jain
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26505, United States
| | - Ashley E Leslie
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26505, United States
| | - Shelli L Frey
- Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26505, United States.,NanoSAFE, P.O. Box 6223, West Virginia University, Morgantown, West Virginia 26506, United States.,The Center for Neurosciences, West Virginia University, Morgantown, West Virginia 26505, United States
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25
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Phuthong W, Huang Z, Wittkopp TM, Sznee K, Heinnickel ML, Dekker JP, Frese RN, Prinz FB, Grossman AR. The Use of Contact Mode Atomic Force Microscopy in Aqueous Medium for Structural Analysis of Spinach Photosynthetic Complexes. PLANT PHYSIOLOGY 2015; 169:1318-32. [PMID: 26220954 PMCID: PMC4587457 DOI: 10.1104/pp.15.00706] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 07/24/2015] [Indexed: 05/02/2023]
Abstract
To investigate the dynamics of photosynthetic pigment-protein complexes in vascular plants at high resolution in an aqueous environment, membrane-protruding oxygen-evolving complexes (OECs) associated with photosystem II (PSII) on spinach (Spinacia oleracea) grana membranes were examined using contact mode atomic force microscopy. This study represents, to our knowledge, the first use of atomic force microscopy to distinguish the putative large extrinsic loop of Photosystem II CP47 reaction center protein (CP47) from the putative oxygen-evolving enhancer proteins 1, 2, and 3 (PsbO, PsbP, and PsbQ) and large extrinsic loop of Photosystem II CP43 reaction center protein (CP43) in the PSII-OEC extrinsic domains of grana membranes under conditions resulting in the disordered arrangement of PSII-OEC particles. Moreover, we observed uncharacterized membrane particles that, based on their physical characteristics and electrophoretic analysis of the polypeptides associated with the grana samples, are hypothesized to be a domain of photosystem I that protrudes from the stromal face of single thylakoid bilayers. Our results are interpreted in the context of the results of others that were obtained using cryo-electron microscopy (and single particle analysis), negative staining and freeze-fracture electron microscopy, as well as previous atomic force microscopy studies.
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Affiliation(s)
- Witchukorn Phuthong
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Zubin Huang
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Tyler M Wittkopp
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Kinga Sznee
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Mark L Heinnickel
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Jan P Dekker
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Raoul N Frese
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Fritz B Prinz
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
| | - Arthur R Grossman
- Department of Materials Science and Engineering (W.P., F.B.P.), Department of Mechanical Engineering (Z.H., F.B.P.), and Department of Biology (T.M.W.), Stanford University, Stanford, California 94305;Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (T.M.W., M.L.H., A.R.G.); andDepartment of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands (K.S., J.P.D., R.N.F.)
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26
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Schuh A, Bozchalooi IS, Rangelow IW, Youcef-Toumi K. Multi-eigenmode control for high material contrast in bimodal and higher harmonic atomic force microscopy. NANOTECHNOLOGY 2015; 26:235706. [PMID: 25994333 DOI: 10.1088/0957-4484/26/23/235706] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
High speed imaging and mapping of nanomechanical properties in atomic force microscopy (AFM) allows the observation and characterization of dynamic sample processes. Recent developments involve several cantilever frequencies in a multifrequency approach. One method actuates the first eigenmode for topography imaging and records the excited higher harmonics to map nanomechanical properties of the sample. To enhance the higher frequencies' response two or more eigenmodes are actuated simultaneously, where the higher eigenmode(s) are used to quantify the nanomechanics. In this paper, we combine each imaging methodology with a novel control approach. It modifies the Q factor and resonance frequency of each eigenmode independently to enhance the force sensitivity and imaging bandwidth. It allows us to satisfy the different requirements for the first and higher eigenmode. The presented compensator is compatible with existing AFMs and can be simply attached with minimal modifications. Different samples are used to demonstrate the improvement in nanomechanical contrast mapping and imaging speed of tapping mode AFM in air. The experiments indicate most enhanced nanomechanical contrast with low Q factors of the first and high Q factors of the higher eigenmode. In this scenario, the cantilever topography imaging rate can also be easily improved by a factor of 10.
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Affiliation(s)
- Andreas Schuh
- Massachusetts Institute of Technology, Department of Mechanical Engineering, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. Ilmenau University of Technology, Faculty of Electrical Engineering and Information Technology, Dept. of Microelectronic and Nanoelectronic Systems, Gustav-Kirchhoff-Str. 1, 98684 Ilmenau, Germany
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27
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Guzman HV, Garcia PD, Garcia R. Dynamic force microscopy simulator (dForce): A tool for planning and understanding tapping and bimodal AFM experiments. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015; 6:369-79. [PMID: 25821676 PMCID: PMC4362491 DOI: 10.3762/bjnano.6.36] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 01/08/2015] [Indexed: 05/23/2023]
Abstract
We present a simulation environment, dForce, which can be used for a better understanding of dynamic force microscopy experiments. The simulator presents the cantilever-tip dynamics for two dynamic AFM methods, tapping mode AFM and bimodal AFM. It can be applied for a wide variety of experimental situations in air or liquid. The code provides all the variables and parameters relevant in those modes, for example, the instantaneous deflection and tip-surface force, velocity, virial, dissipated energy, sample deformation and peak force as a function of time or distance. The simulator includes a variety of interactions and contact mechanics models to describe AFM experiments including: van der Waals, Hertz, DMT, JKR, bottom effect cone correction, linear viscoelastic forces or the standard linear solid viscoelastic model. We have compared two numerical integration methods to select the one that offers optimal accuracy and speed. The graphical user interface has been designed to facilitate the navigation of non-experts in simulations. Finally, the accuracy of dForce has been tested against numerical simulations performed during the last 18 years.
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Affiliation(s)
- Horacio V Guzman
- Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juan Inés de la Cruz 3, 28049 Madrid, Spain
| | - Pablo D Garcia
- Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juan Inés de la Cruz 3, 28049 Madrid, Spain
| | - Ricardo Garcia
- Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juan Inés de la Cruz 3, 28049 Madrid, Spain
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28
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Shamitko-Klingensmith N, Legleiter J. Investigation of temperature induced mechanical changes in supported bilayers by variants of tapping mode atomic force microscopy. SCANNING 2015; 37:23-35. [PMID: 25369473 DOI: 10.1002/sca.21175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/28/2014] [Accepted: 10/06/2014] [Indexed: 06/04/2023]
Abstract
Tapping mode atomic force microscopy (AFM) is an invaluable technique for examining topographical features of biological materials in solution, and there has been a growing interest in developing techniques to provide further compositional contrast and information concerning surface mechanical properties. Phase shifts, cantilever response at higher harmonic frequencies of the drive, and time-resolved tip/sample force reconstruction have all been shown to provide additional compositional contrast of surfaces, as compared to basic tapping mode AFM imaging. This study aimed to demonstrate the relative ability of these different imaging techniques to detect temperature induced changes in the elastic modulus of supported total brain lipid extract (TBLE) bilayer patches on mica. To aid in direct comparison between the different imaging techniques, all required data was obtained simultaneously while capturing traditional tapping mode AFM topography images. While all of the techniques were able to provide compositional contrast consistent with known temperature-induced changes in the bilayer patch, interpretation of the resulting contrast was not always straightforward. Phase imaging suffered from contrast inversion. Individual harmonics responded in a variety of ways to the temperature-induced changes in elastic modulus of the bilayer. The maximum tapping force (or peak force) associated with imaging the bilayer correctly reflected the changes in elastic modulus of the lipid bilayer. Importantly, as the required data can be obtained simultaneously, combining these different imaging techniques can lead to a more complete understanding of a sample's mechanical features.
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Affiliation(s)
- Nicole Shamitko-Klingensmith
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia; NanoSAFE, West Virginia University, Morgantown, West Virginia
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29
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An S, Solares SD, Santos S, Ebeling D. Energy transfer between eigenmodes in multimodal atomic force microscopy. NANOTECHNOLOGY 2014; 25:475701. [PMID: 25369864 DOI: 10.1088/0957-4484/25/47/475701] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We present experimental and computational investigations of tetramodal and pentamodal atomic force microscopy (AFM), respectively, whereby the first four or five flexural eigenmodes of the cantilever are simultaneously excited externally. This leads to six to eight additional observables in the form of amplitude and phase signals, with respect to the monomodal amplitude modulation method. We convert these additional observables into three or four dissipation and virial expressions, and show that these quantities can provide enhanced contrast that would otherwise remain hidden in the original observables. We also show that the complexity of the multimodal impact leads to significant energy transfer between the active eigenmodes, such that the dissipated power for individual eigenmodes may be positive or negative, while the total dissipated power remains positive. These results suggest that the contrast of individual eigenmodes in multifrequency AFM should be not be considered in isolation and that it may be possible to use different eigenfrequencies to probe sample properties that respond to different relaxation times.
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Affiliation(s)
- Sangmin An
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA. Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
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30
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Zhang S, Aslan H, Besenbacher F, Dong M. Quantitative biomolecular imaging by dynamic nanomechanical mapping. Chem Soc Rev 2014; 43:7412-29. [DOI: 10.1039/c4cs00176a] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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31
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Lü J, Yang J, Dong M, Sahin O. Nanomechanical spectroscopy of synthetic and biological membranes. NANOSCALE 2014; 6:7604-8. [PMID: 24895687 DOI: 10.1039/c3nr02643d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We report that atomic force microscopy based high-speed nanomechanical analysis can identify components of complex heterogeneous synthetic and biological membranes from the measured spectrum of nanomechanical properties. We have investigated phase separated ternary lipid bilayers and purple membranes of Halobacterium salinarum. The nanomechanical spectra recorded on these samples identify all membrane components, some of which are difficult to resolve in conventional phase images. This non-destructive approach can aid the design of synthetic lipid bilayers and studies lateral organization of complex heterogeneous cellular membranes.
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Affiliation(s)
- Junhong Lü
- The Rowland Institute at Harvard, Harvard University, Cambridge, MA, USA
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32
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Shih PJ. Frequency function in atomic force microscopy applied to a liquid environment. SENSORS 2014; 14:9369-79. [PMID: 24865882 PMCID: PMC4118394 DOI: 10.3390/s140609369] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 05/20/2014] [Accepted: 05/20/2014] [Indexed: 11/16/2022]
Abstract
Scanning specimens in liquids using commercial atomic force microscopy (AFM) is very time-consuming due to the necessary try-and-error iteration for determining appropriate triggering frequencies and probes. In addition, the iteration easily contaminates the AFM tip and damages the samples, which consumes probes. One reason for this could be inaccuracy in the resonant frequency in the feedback system setup. This paper proposes a frequency function which varies with the tip-sample separation, and it helps to improve the frequency shift in the current feedback system of commercial AFMs. The frequency function is a closed-form equation, which allows for easy calculation, as confirmed by experimental data. It comprises three physical effects: the quasi-static equilibrium condition, the atomic forces gradient effect, and hydrodynamic load effect. While each of these has previously been developed in separate studies, this is the first time their combination has been used to represent the complete frequency phenomenon. To avoid "jump to contact" issues, experiments often use probes with relatively stiffer cantilevers, which inevitably reduce the force sensitivity in sensing low atomic forces. The proposed frequency function can also predict jump to contact behavior and, thus, the probe sensitivity could be increased and soft probes could be widely used. Additionally, various tip height behaviors coupling with the atomic forces gradient and hydrodynamic effects are discussed in the context of carbon nanotube probes.
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Affiliation(s)
- Po-Jen Shih
- Department of Civil and Environmental Engineering, National University of Kaohsiung, CEE NUK, No. 700, Kaohsiung University Rd., Nanzih District, 81148, Kaohsiung, Taiwan.
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33
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Solares SD. Challenges and complexities of multifrequency atomic force microscopy in liquid environments. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:298-307. [PMID: 24778952 PMCID: PMC3999742 DOI: 10.3762/bjnano.5.33] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 02/18/2014] [Indexed: 05/26/2023]
Abstract
This paper illustrates through numerical simulation the complexities encountered in high-damping AFM imaging, as in liquid enviroments, within the specific context of multifrequency atomic force microscopy (AFM). The focus is primarily on (i) the amplitude and phase relaxation of driven higher eigenmodes between successive tip-sample impacts, (ii) the momentary excitation of non-driven higher eigenmodes and (iii) base excitation artifacts. The results and discussion are mostly applicable to the cases where higher eigenmodes are driven in open loop and frequency modulation within bimodal schemes, but some concepts are also applicable to other types of multifrequency operations and to single-eigenmode amplitude and frequency modulation methods.
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Affiliation(s)
- Santiago D Solares
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
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34
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de Pablo PJ, Carrión-Vázquez M. Imaging biological samples with atomic force microscopy. Cold Spring Harb Protoc 2014; 2014:167-77. [PMID: 24492779 DOI: 10.1101/pdb.top080473] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Atomic force microscopy (AFM) is an invaluable tool both for obtaining high-resolution topographical images and for determining the values of mechanical and structural properties of specimens adsorbed onto a surface. AFM is useful in an array of fields and applications, from materials science to biology. It is an extremely versatile technique that can be applied to almost any surface-mounted sample and can be operated in ambient air, ultrahigh vacuum, and, most importantly for biology, liquids. AFM can be used to explore samples ranging in size from atoms to molecules, molecular aggregates, and cells. Individual biomolecules can be viewed and manipulated at the nanoscale, providing fundamental biological information. In particular, the study of the mechanical properties of biomolecular aggregates at the nanoscale constitutes an important source of data to elaborate mechanochemical structure/function models of single-particle biomachines, expanding and complementing the information obtained from bulk experiments.
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35
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Herruzo ET, Perrino AP, Garcia R. Fast nanomechanical spectroscopy of soft matter. Nat Commun 2014; 5:3126. [DOI: 10.1038/ncomms4126] [Citation(s) in RCA: 187] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 12/16/2013] [Indexed: 12/23/2022] Open
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36
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Wasem M, Köser J, Hess S, Gnecco E, Meyer E. Exploring the retention properties of CaF2 nanoparticles as possible additives for dental care application with tapping-mode atomic force microscope in liquid. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:36-43. [PMID: 24455460 PMCID: PMC3896269 DOI: 10.3762/bjnano.5.4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 12/10/2013] [Indexed: 06/03/2023]
Abstract
Amplitude-modulation atomic force microscopy (AM-AFM) is used to determine the retention properties of CaF2 nanoparticles adsorbed on mica and on tooth enamel in liquid. From the phase-lag of the forced cantilever oscillation the local energy dissipation at the detachment point of the nanoparticle was determined. This enabled us to compare different as-synthesized CaF2 nanoparticles that vary in shape, size and surface structure. CaF2 nanoparticles are candidates for additives in dental care products as they could serve as fluorine-releasing containers preventing caries during a cariogenic acid attack on the teeth. We show that the adherence of the nanoparticles is increased on the enamel substrate compared to mica, independently of the substrate roughness, morphology and size of the particles.
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Affiliation(s)
- Matthias Wasem
- Department of Physics, University of Basel, Klingelbergstrasse 82, Basel 4056, Switzerland
| | - Joachim Köser
- Institute for Chemistry and Bioanalytics, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz 4132, Switzerland
| | - Sylvia Hess
- GABA International AG, Grabetsmattweg, 4106 Therwil, Switzerland
| | - Enrico Gnecco
- Instituto Madrileño de Estudios Avanzados, IMDEA Nanociencia, 28049 Madrid, Spain
| | - Ernst Meyer
- Department of Physics, University of Basel, Klingelbergstrasse 82, Basel 4056, Switzerland
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37
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Pukhova V, Banfi F, Ferrini G. Complex force dynamics in atomic force microscopy resolved by wavelet transforms. NANOTECHNOLOGY 2013; 24:505716. [PMID: 24285087 DOI: 10.1088/0957-4484/24/50/505716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The amplitude and phase evolution of the oscillations of a cantilever after a single tip-sample impact are investigated using a cross-correlation wavelet analysis. The excitation of multiple flexural modes is evidenced and the instantaneous amplitude and phase evolution is extracted from the experimental data at all frequencies simultaneously. The instantaneous total force acting on the tip during a single impact is reconstructed. This method has general relevance for the development of an atomic force spectroscopy of single tip-sample interactions, that develop in a few oscillation cycles of the interacting cantilever eigenmodes and their harmonics.
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Affiliation(s)
- Valentina Pukhova
- i-LAMP and Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, I-25121 Brescia, Italy. Dipartimento di Fisica, Università degli Studi di Milano, I-20122 Milano, Italy
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38
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Yang CW, Ding RF, Lai SH, Liao HS, Lai WC, Huang KY, Chang CS, Hwang IS. Torsional resonance mode atomic force microscopy in liquid with Lorentz force actuation. NANOTECHNOLOGY 2013; 24:305702. [PMID: 23807471 DOI: 10.1088/0957-4484/24/30/305702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this work, we present a design based on Lorentz force induction to excite pure torsional resonances of different types of cantilevers in air as well as in water. To demonstrate the atomic force microscopy imaging capability, the phase-modulation torsional resonance mode is employed to resolve fine features of purple membranes in a buffer solution. Most importantly, force-versus-distance curves using a relatively stiff cantilever can clearly detect the characteristic oscillatory profiles of hydration layers at a water-mica interface, indicating the high force sensitivity of the torsional mode. The high resonance frequencies and high quality-factors for the torsional mode may be of great potential for high-speed and high-sensitivity imaging in aqueous environment.
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Affiliation(s)
- Chih-Wen Yang
- Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan, Republic of China.
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39
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40
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Saraswat G, Agarwal P, Haugstad G, Salapaka MV. Real-time probe based quantitative determination of material properties at the nanoscale. NANOTECHNOLOGY 2013; 24:265706. [PMID: 23735280 DOI: 10.1088/0957-4484/24/26/265706] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Tailoring the properties of a material at the nanoscale holds the promise of achieving hitherto unparalleled specificity of the desired behavior of the material. Key to realizing this potential of tailoring materials at the nanoscale are methods for rapidly estimating physical properties of the material at the nanoscale. In this paper, we report a method for simultaneously determining the topography, stiffness and dissipative properties of materials at the nanoscale in a probe based dynamic mode operation. The method is particularly suited for investigating soft-matter such as polymers and bio-matter. We use perturbation analysis tools for mapping dissipative and stiffness properties of material into parameters of an equivalent linear time-invariant model. Parameters of the equivalent model are adaptively estimated, where, for robust estimation, a multi-frequency excitation of the probe is introduced. We demonstrate that the reported method of simultaneously determining multiple material properties can be implemented in real-time on existing probe based instruments. We further demonstrate the effectiveness of the method by investigating properties of a polymer blend in real-time.
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Affiliation(s)
- G Saraswat
- Department of Electrical and Computer Engineering, University of Minnesota-Twin Cities, USA
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41
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Cartagena A, Hernando-Pérez M, Carrascosa JL, de Pablo PJ, Raman A. Mapping in vitro local material properties of intact and disrupted virions at high resolution using multi-harmonic atomic force microscopy. NANOSCALE 2013; 5:4729-4736. [PMID: 23598736 DOI: 10.1039/c3nr34088k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Understanding the relationships between viral material properties (stiffness, strength, charge density, adhesion, hydration, viscosity, etc.), structure (protein sub-units, genome, surface receptors, appendages), and functions (self-assembly, stability, disassembly, infection) is of significant importance in physical virology and nanomedicine. Conventional Atomic Force Microscopy (AFM) methods have measured a single physical property such as the stiffness of the entire virus from nano-indentation at a few points which severely limits the study of structure-property-function relationships. We present an in vitro dynamic AFM technique operating in the intermittent contact regime which synthesizes anharmonic Lorentz-force excited AFM cantilevers to map quantitatively at nanometer resolution the local electro-mechanical force gradient, adhesion, and hydration layer viscosity within individual φ29 virions. Furthermore, the changes in material properties over the entire φ29 virion provoked by the local disruption of its shell are studied, providing evidence of bacteriophage depressurization. The technique significantly generalizes recent multi-harmonic theory (A. Raman, et al., Nat. Nanotechnol., 2011, 6, 809-814) and enables high-resolution in vitro quantitative mapping of multiple material properties within weakly bonded viruses and nanoparticles with complex structure that otherwise cannot be observed using standard AFM techniques.
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Affiliation(s)
- Alexander Cartagena
- Birck Nanotechnology Center & School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA
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42
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Ebeling D, Solares SD. Amplitude modulation dynamic force microscopy imaging in liquids with atomic resolution: comparison of phase contrasts in single and dual mode operation. NANOTECHNOLOGY 2013; 24:135702. [PMID: 23478354 DOI: 10.1088/0957-4484/24/13/135702] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We present a systematic analysis of the atomic-scale imaging capabilities for mineral surfaces in a liquid environment in single and dual mode amplitude modulation dynamic force microscopy. To study the difference in sensitivity between the first and second eigenmode phase signals we investigate the observed atomic-scale contrasts of the mica-water interface under varying imaging conditions. For this purpose, we systematically change the main imaging parameters including the setpoint amplitude of the imaging feedback, the free oscillation amplitudes of the first and second flexural eigenmodes, and their ratio. This allows for an in-depth analysis of the sensitivities of the first and second eigenmode phase signals to draw conclusions regarding the underlying physical mechanisms and the interpretation of the contrast in the multi-frequency technique.
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Affiliation(s)
- Daniel Ebeling
- Department of Mechanical Engineering, University of Maryland, 2181 Glenn L Martin Hall, College Park, MD 20742, USA.
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43
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Santos S, Billingsley D, Thomson N. Atomic force microscopy imaging of macromolecular complexes. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2013; 950:315-41. [PMID: 23086883 DOI: 10.1007/978-1-62703-137-0_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
This chapter reviews amplitude modulation (AM) AFM in air and its applications to high-resolution imaging and interpretation of macromolecular complexes. We discuss single DNA molecular imaging and DNA-protein interactions, such as those with topoisomerases and RNA polymerase. We show how relative humidity can have a major influence on resolution and contrast and how it can also affect conformational switching of supercoiled DNA. Four regimes of AFM tip-sample interaction in air are defined and described, and relate to water perturbation and/or intermittent mechanical contact of the tip with either the molecular sample or the surface. Precise control and understanding of the AFM operational parameters is shown to allow the user to switch between these different regimes: an interpretation of the origins of topographical contrast is given for each regime. Perpetual water contact is shown to lead to a high-resolution mode of operation, which we term SASS (small amplitude small set-point) imaging, and which maximizes resolution while greatly decreasing tip and sample wear and any noise due to perturbation of the surface water. Thus, this chapter provides sufficient information to reliably control the AFM in the AM AFM mode of operation in order to image both heterogeneous samples and single macromolecules including complexes, with high resolution and with reproducibility. A brief introduction to AFM, its versatility and applications to biology is also given while providing references to key work and general reviews in the field.
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Affiliation(s)
- Sergio Santos
- Department of Oral Biology, University of Leeds, Leeds, UK
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44
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Kiracofe D, Raman A, Yablon D. Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2013; 4:385-93. [PMID: 23844344 PMCID: PMC3701429 DOI: 10.3762/bjnano.4.45] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 05/17/2013] [Indexed: 05/20/2023]
Abstract
One of the key goals in atomic force microscopy (AFM) imaging is to enhance material property contrast with high resolution. Bimodal AFM, where two eigenmodes are simultaneously excited, confers significant advantages over conventional single-frequency tapping mode AFM due to its ability to provide contrast between regions with different material properties under gentle imaging conditions. Bimodal AFM traditionally uses the first two eigenmodes of the AFM cantilever. In this work, the authors explore the use of higher eigenmodes in bimodal AFM (e.g., exciting the first and fourth eigenmodes). It is found that such operation leads to interesting contrast reversals compared to traditional bimodal AFM. A series of experiments and numerical simulations shows that the primary cause of the contrast reversals is not the choice of eigenmode itself (e.g., second versus fourth), but rather the relative kinetic energy between the higher eigenmode and the first eigenmode. This leads to the identification of three distinct imaging regimes in bimodal AFM. This result, which is applicable even to traditional bimodal AFM, should allow researchers to choose cantilever and operating parameters in a more rational manner in order to optimize resolution and contrast during nanoscale imaging of materials.
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Affiliation(s)
- Daniel Kiracofe
- Purdue University School of Mechanical Engineering, West Lafayette, IN, USA
- ExxonMobil Research and Engineering Co., Annandale, NJ, USA
| | - Arvind Raman
- Purdue University School of Mechanical Engineering, West Lafayette, IN, USA
| | - Dalia Yablon
- ExxonMobil Research and Engineering Co., Annandale, NJ, USA
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45
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Melcher J, Martínez-Martín D, Jaafar M, Gómez-Herrero J, Raman A. High-resolution dynamic atomic force microscopy in liquids with different feedback architectures. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2013; 4:153-63. [PMID: 23503468 PMCID: PMC3596120 DOI: 10.3762/bjnano.4.15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 01/24/2013] [Indexed: 05/23/2023]
Abstract
The recent achievement of atomic resolution with dynamic atomic force microscopy (dAFM) [Fukuma et al., Appl. Phys. Lett. 2005, 87, 034101], where quality factors of the oscillating probe are inherently low, challenges some accepted beliefs concerning sensitivity and resolution in dAFM imaging modes. Through analysis and experiment we study the performance metrics for high-resolution imaging with dAFM in liquid media with amplitude modulation (AM), frequency modulation (FM) and drive-amplitude modulation (DAM) imaging modes. We find that while the quality factors of dAFM probes may deviate by several orders of magnitude between vacuum and liquid media, their sensitivity to tip-sample forces can be remarkable similar. Furthermore, the reduction in noncontact forces and quality factors in liquids diminishes the role of feedback control in achieving high-resolution images. The theoretical findings are supported by atomic-resolution images of mica in water acquired with AM, FM and DAM under similar operating conditions.
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Affiliation(s)
- John Melcher
- Department of Engineering Mathematics, University of Bristol, Bristol BS8 1TR, United Kingdom
| | - David Martínez-Martín
- ETH Zürich, Department of Biosystems Science and Engineering, CH-4058 Basel, Switzerland
| | - Miriam Jaafar
- Departamento de Física de la Materia Condensada C-III, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Julio Gómez-Herrero
- Departamento de Física de la Materia Condensada C-III, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Arvind Raman
- School of Mechanical Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907
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Abstract
Atomic force microscopy (AFM) is a helpful tool to acquire nanometric-resolution images, and also to perform a certain physical characterization of specimens, including their stiffness and mechanical resilience. Besides of the wide range of applications, from materials science to biology, this technique works in a variety of conditions as long as the sample is supported on a solid surface, in air, ultra high vacuum or, most importantly for virus research, in liquids. The adaptability of this technique is also fostered by the variety of sizes of the specimens that it can dealt with, such as atoms, molecules, molecular complexes including viruses and cells, and the possibility to observe dynamic processes in real time. Indeed, AFM facilitates single molecule experiments enabling not only to see but also to touch the material under study (i.e., to undertake mechanical manipulations), and constitutes a fundamental source of information for material characterization. In particular, the study of the mechanical properties at the nanoscale of viruses and other biomolecular aggregates, is providing an important set of data which help to elaborate mechano-chemical structure/function models of molecular biomachines, expanding and complementing the information obtained by other structural techniques.
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Affiliation(s)
- Pedro J de Pablo
- Department of Physics of the Condensed Matter, C03, Facultad de Ciencias, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049, Madrid, Spain,
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47
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Labuda A, Lysy M, Paul W, Miyahara Y, Grütter P, Bennewitz R, Sutton M. Stochastic noise in atomic force microscopy. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:031104. [PMID: 23030863 DOI: 10.1103/physreve.86.031104] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Indexed: 06/01/2023]
Abstract
Having reached the quantum and thermodynamic limits of detection, atomic force microscopy (AFM) experiments are routinely being performed at the fundamental limit of signal to noise. A critical understanding of the statistical properties of noise leads to more accurate interpretation of data, optimization of experimental protocols, advancements in instrumentation, and new measurement techniques. Furthermore, accurate simulation of cantilever dynamics requires knowledge of stochastic behavior of the system, as stochastic noise may exceed the deterministic signals of interest, and even dominate the outcome of an experiment. In this article, the power spectral density (PSD), used to quantify stationary stochastic processes, is introduced in the context of a thorough noise analysis of the light source used to detect cantilever deflections. The statistical properties of PSDs are then outlined for various stationary, nonstationary, and deterministic noise sources in the context of AFM experiments. Following these developments, a method for integrating PSDs to provide an accurate standard deviation of linear measurements is described. Lastly, a method for simulating stochastic Gaussian noise from any arbitrary power spectral density is presented. The result demonstrates that mechanical vibrations of the AFM can cause a logarithmic velocity dependence of friction and induce multiple slip events in the atomic stick-slip process, as well as predicts an artifactual temperature dependence of friction measured by AFM.
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Affiliation(s)
- Aleksander Labuda
- Department of Physics, McGill University, Montreal, Quebec, Canada H3A 2T8
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48
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Santos S, Verdaguer A, Chiesa M. The effects of adsorbed water layers on the apparent height of nanostructures in ambient amplitude modulation atomic force microscopy. J Chem Phys 2012; 137:044201. [DOI: 10.1063/1.4737516] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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49
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Payam AF, Ramos JR, Garcia R. Molecular and nanoscale compositional contrast of soft matter in liquid: interplay between elastic and dissipative interactions. ACS NANO 2012; 6:4663-70. [PMID: 22578176 DOI: 10.1021/nn2048558] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We demonstrate that the phase contrast observed with an amplitude modulation atomic force microscope depends on two factors, the generation of higher harmonics components and the energy dissipated on the sample surface. Those factors are ultimately related to the chemical composition and structure of the surface. Our findings are general, but they specifically describe the results obtained while imaging soft materials in liquid. Molecular resolution experiments performed on a protein membrane surface in liquid confirm the theory.
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Affiliation(s)
- Amir F Payam
- IMM-Instituto de Microelectrónica de Madrid, CSIC, Isaac Newton 8, Tres Cantos, 28760 Madrid, Spain
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50
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Santos S, Gadelrab KR, Souier T, Stefancich M, Chiesa M. Quantifying dissipative contributions in nanoscale interactions. NANOSCALE 2012; 4:792-800. [PMID: 22159043 DOI: 10.1039/c1nr10954e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Imaging with nanoscale resolution has become routine practice with the use of scanning probe techniques. Nevertheless, quantification of material properties and processes has been hampered by the complexity of the tip-surface interaction and the dependency of the dynamics on operational parameters. Here, we propose a framework for the quantification of the coefficients of viscoelasticity, surface energy, surface energy hysteresis and elastic modulus. Quantification of these parameters at the nanoscale will provide a firm ground to the understanding and modelling of tribology and nanoscale sciences with true nanoscale resolution.
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Affiliation(s)
- Sergio Santos
- Laboratory of Energy and Nanosciences, Masdar Institute of Science and Technology, Abu Dhabi, UAE
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