Mapping in vitro local material properties of intact and disrupted virions at high resolution using multi-harmonic atomic force microscopy

Nanoscale ◽  
2013 ◽  
Vol 5 (11) ◽  
pp. 4729 ◽  
Author(s):  
Alexander Cartagena ◽  
Mercedes Hernando-Pérez ◽  
José L. Carrascosa ◽  
Pedro J. de Pablo ◽  
Arvind Raman
Keyword(s):  
Atomic Force Microscopy ◽  
High Resolution ◽  
Material Properties ◽  
Force Microscopy ◽  
Atomic Force ◽  
Local Material ◽  
Local Material Properties

scholarly journals Combining adhesive contact mechanics with a viscoelastic material model to probe local material properties by AFM

Soft Matter ◽  
2018 ◽  
Vol 14 (1) ◽  
pp. 140-150 ◽  
Author(s):  
Christian Ganser ◽  
Caterina Czibula ◽  
Daniel Tscharnuter ◽  
Thomas Schöberl ◽  
Christian Teichert ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Viscoelastic Material ◽  
Material Properties ◽  
Material Model ◽  
Adhesive Contact ◽  
Force Microscopy ◽  
Atomic Force ◽  
Local Material ◽  
Local Material Properties

We present an atomic force microscopy based method to study viscoelastic material properties at low indentation depths with non-negligible adhesion and surface roughness.

scholarly journals Unraveling the Architecture and Structural Dynamics of Pathogens by High-Resolution in vitro Atomic Force Microscopy

2005 ◽  
Vol 11 (S03) ◽  
pp. 32-35 ◽  
Author(s):  
A. J. Malkin ◽  
M. Plomp ◽  
T. J. Leighton ◽  
A. McPherson ◽  
K. E. Wheeler
Keyword(s):  
Atomic Force Microscopy ◽  
High Resolution ◽  
Crystallographic Analysis ◽  
Human Pathogens ◽  
Force Microscopy ◽  
Environmental Resistance ◽  
Macromolecular Assemblies ◽  
Atomic Force ◽  
Internal Structures

Progress in structural biology very much depends upon the development of new high-resolution techniques and tools. Despite decades of study of viruses, bacteria and bacterial spores and their pressing importance in human medicine and biodefense, many of their structural properties are poorly understood. Thus, characterization and understanding of the architecture of protein surface and internal structures of pathogens is critical to elucidating mechanisms of disease, immune response, physicochemical properties, environmental resistance and development of countermeasures against bioterrorist agents. Furthermore, even though complete genome sequences are available for various pathogens, the structure-function relationships are not understood. Because of their lack of symmetry and heterogeneity, large human pathogens are often refractory to X-ray crystallographic analysis or reconstruction by cryo-electron microscopy (cryo-EM). An alternative high-resolution method to examine native structure of pathogens is atomic force microscopy (AFM), which allows direct visualization of macromolecular assemblies at near-molecular resolution. The capability to image single pathogen surfaces at nanometer scale in vitro would profoundly impact mechanistic and structural studies of Progress in structural biology very much depends upon the development of new high-resolution techniques and tools. Despite decades of study of viruses, bacteria and bacterial spores and their pressing importance in human medicine and biodefense, many of their structural properties are poorly understood. Thus, characterization and understanding of the architecture of protein surface and internal structures of pathogens is critical to elucidating mechanisms of disease, immune response, physicochemical properties, environmental resistance and development of countermeasures against bioterrorist agents. Furthermore, even though complete genome sequences are available for various pathogens, the structure-function relationships are not understood. Because of their lack of symmetry and heterogeneity, large human pathogens are often refractory to X-ray crystallographic analysis or reconstruction by cryo-electron microscopy (cryo-EM). An alternative high-resolution method to examine native structure of pathogens is atomic force microscopy (AFM), which allows direct visualization of macromolecular assemblies at near-molecular resolution. The capability to image single pathogen surfaces at nanometer scale in vitro would profoundly impact mechanistic and structural studies of pathogenesis, immunobiology, specific cellular processes, environmental dynamics and biotransformation.

Localized Material Properties Through Nonlinear Dynamics Based Atomic Force Microscopy

2010 ◽  
Author(s):  
Wei Huang ◽  
Andrew J. Dick
Keyword(s):  
Atomic Force Microscopy ◽  
Material Properties ◽  
Period Doubling ◽  
Nonlinear Behavior ◽  
Separation Distance ◽  
Resonance Excitation ◽  
Current Effort ◽  
Force Microscopy ◽  
Atomic Force ◽  
Local Material Properties

Due to the intrinsic nonlinearity of the tip-sample interaction forces that are utilized in atomic force microscopy, nonlinear behavior can be observed even under the most ‘ideal’ conditions. While the standard operating modes of the atomic force microscope (AFM) have been developed to minimize this nonlinear behavior, the authors’ work focuses on utilizing a nonlinear response of the AFM probe associated with off-resonance excitation in order to measure local material properties of the sample. Previously, period-doubling bifurcations were identified and studied for an off-resonance excitation condition of two-and-a-half times the fundamental frequency. A relationship was identified between the characteristics of the qualitative response transition and the properties of the probe and sample. For a given probe, the critical separation distance where the period-doubling bifurcation occurs is influenced by the local modulus properties of the sample. This paper details the current effort studying this relationship with the goal of developing a new AFM operation mode for obtaining localized material properties by scanning the sample. The influence of different system parameters on this relationship is studied and preliminary simulation results are presented for a simple scanning process.

scholarly journals Exploring Intramolecular Methyl–Methyl Coupling on a Metal Surface for Edge-Extended Graphene Nanoribbons

2021 ◽  
Vol 03 (02) ◽  
pp. 128-133
Author(s):  
Zijie Qiu ◽  
Qiang Sun ◽  
Shiyong Wang ◽  
Gabriela Borin Barin ◽  
Bastian Dumslaff ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Atomic Force Microscopy ◽  
High Resolution ◽  
Graphene Nanoribbons ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
Methyl Methyl ◽  
Atomic Force ◽  
Edge Extension

Intramolecular methyl–methyl coupling on Au (111) is explored as a new on-surface protocol for edge extension in graphene nanoribbons (GNRs). Characterized by high-resolution scanning tunneling microscopy, noncontact atomic force microscopy, and Raman spectroscopy, the methyl–methyl coupling is proven to indeed proceed at the armchair edges of the GNRs, forming six-membered rings with sp3- or sp2-hybridized carbons.

Sign in / Sign up

Export Citation Format

Share Document