Surface charges and adhesion measured by atomic force microscope influence on friction force

Potential dependence of the friction force between an atomically-flat terrace of Au(100) single crystal and a tip attached to a silicon nitride cantilever of electrochemical atomic force microscope (EC-AFM) have been investigated qualitatively in 0.05 M H2SO4 aqueous solution. It is found that the friction force gains when the potential increases in the potential range between −400 mV and 400 mV vs Hg/Hg2SO4 electrode.

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Contributions of lunate cells and wax crystals to the surface anisotropy of Nepenthes slippery zone

Royal Society Open Science ◽

10.1098/rsos.180766 ◽

2018 ◽

Vol 5 (9) ◽

pp. 180766 ◽

Cited By ~ 1

Author(s):

Lixin Wang ◽

Dashuai Tao ◽

Shiyun Dong ◽

Shanshan Li ◽

Yu Tian

Keyword(s):

Atomic Force Microscope ◽

Surface Topography ◽

Friction Force ◽

Body Length ◽

Structural Features ◽

Large Displacements ◽

Surface Anisotropy ◽

Atomic Force ◽

Microstructure Examination ◽

Wax Crystals

Nepenthes slippery zone presents surface anisotropy depending on its specialized structures. Herein, via macro–micro–nano scaled experiments, we analysed the contributions of lunate cells and wax crystals to this anisotropy. Macroscopic climbing of insects showed large displacements (triple body length within 3 s) and high velocities (6.16–20.47 mm s −1 ) in the inverted-fixed (towards digestive zone) slippery zone, but failed to climb forward in the normal-fixed (towards peristome) one. Friction force of insect claws sliding across inverted-fixed lunate cells was about 2.4 times of that sliding across the normal-fixed ones, whereas showed unobvious differences (1.06–1.11 times) between the inverted- and normal-fixed wax crystals. Innovative results from atomic force microscope scanning and microstructure examination demonstrated the upper layer of wax crystals causes the cantilever tip to generate rather small differences in friction data (1.92–2.72%), and the beneath layer provides slightly higher differences (4.96–7.91%). The study confirms the anisotropic configuration of lunate cells produces most of the anisotropy, whereas both surface topography and structural features of the wax crystals generate a slight contribution. These results are helpful for understanding the surface anisotropy of Nepenthes slippery zone, and guide the design of bioinspired surface with anisotropic properties.

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AFM Imagings of Ferritin Molecules Bound to LB Films of Poly-1-Benzyl-L-Histidine: Imaging the ordered arrays of water-soluble protein ferritin with the atomic force microscope

MRS Proceedings ◽

10.1557/proc-295-145 ◽

1992 ◽

Vol 295 ◽

Cited By ~ 2

Author(s):

Satomi Ohnishi ◽

Masahiko Hara ◽

Taiji Furuno ◽

Wolfgang Knoll ◽

Hiroyuki Sasabe

Keyword(s):

Atomic Force Microscope ◽

Soluble Protein ◽

Pure Water ◽

Sample Surface ◽

Water Soluble ◽

Surface Charges ◽

Atomic Force ◽

Water Soluble Protein ◽

Electrostatic Binding ◽

Hexagonal Arrangement

AbstractA water-soluble protein, ferritin, on a silicon surface has been imaged in pure water at room temperature with the atomic force microscope (AFM). The samples were prepared by binding ferritin molecules electrostatically to a charged polypeptide layer of poly-l-benzyl-L-histidine (PBLH). The hexagonal arrangement of ferritin molecules was imaged with high reproducibility, since the force between tip and the sample surface could be kept sufficiently lower than 10-10 N. The applied force can be stabilized and weakened mainly due to a “self-screening effect” of the surface charges of the ferritin-PBLH layer. We demonstrate that the electrostatic-binding sample preparation is one of the suitable methods for soft biological specimens to achieve the nondestructive. low-force AFM imagings.

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Friction force studies on layered materials using an Atomic Force Microscope

Surface Science ◽

10.1016/s0039-6028(97)00358-0 ◽

1997 ◽

Vol 387 (1-3) ◽

pp. 227-235 ◽

Cited By ~ 17

Author(s):

H. Klein ◽

D. Pailharey ◽

Y. Mathey

Keyword(s):

Atomic Force Microscope ◽

Friction Force ◽

Layered Materials ◽

Atomic Force

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Preparation and Tribological Behavior of PAH/PAA Molecular Deposition Films

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63166 ◽

2005 ◽

Author(s):

Deguo Wang ◽

Xuexin Yu ◽

Siwei Zhang ◽

Dapeng Feng

Keyword(s):

Atomic Force Microscope ◽

Friction Force ◽

Glass Substrate ◽

Tribological Behavior ◽

Lateral Force ◽

Atomic Force ◽

Number Of Layers ◽

In The Beginning ◽

Deposition Technology ◽

Increasing Load

PAH/PAA polymer multilayer ultrathin film was prepared by molecular deposition technology. The morphology and nano-tribological behaviors of the film were investigated by using atomic force microscope (AFM). It has been found that the friction force of the PAH/PAA polymer molecular deposition film is obviously less then that of the glass substrate, and the friction force increased with increasing load. However, the friction force decreased in the beginning and increased in the sequel with increase in the number of layers, which might be attributed to the change of surface topography with different layers. Moreover, it was found that the profile of both topography and lateral force has good coherence by analyzing the AFM images.

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Quantitative Friction-Force Measurements by Longitudinal Atomic Force Microscope Imaging

Langmuir ◽

10.1021/la900005z ◽

2009 ◽

Vol 25 (11) ◽

pp. 6203-6213 ◽

Cited By ~ 9

Author(s):

Eric Karhu ◽

Mark Gooyers ◽

Jeffrey L. Hutter

Keyword(s):

Atomic Force Microscope ◽

Friction Force ◽

Force Measurements ◽

Atomic Force ◽

Microscope Imaging

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Characterization of photosystem II with the atomic-force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130365 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1146-1147

Author(s):

Kathleen M. Marr ◽

Mary K. Lyon

Keyword(s):

Photosystem Ii ◽

Atomic Force Microscope ◽

Three Dimensional ◽

Biologically Active ◽

Atomic Force ◽

Freeze Etching ◽

Image Averaging ◽

Oxygen Evolving ◽

Averaging Techniques

Photosystem II (PSII) is different from all other reaction centers in that it splits water to evolve oxygen and hydrogen ions. This unique ability to evolve oxygen is partly due to three oxygen evolving polypeptides (OEPs) associated with the PSII complex. Freeze etching on grana derived insideout membranes revealed that the OEPs contribute to the observed tetrameric nature of the PSIl particle; when the OEPs are removed, a distinct dimer emerges. Thus, the surface of the PSII complex changes dramatically upon removal of these polypeptides. The atomic force microscope (AFM) is ideal for examining surface topography. The instrument provides a topographical view of individual PSII complexes, giving relatively high resolution three-dimensional information without image averaging techniques. In addition, the use of a fluid cell allows a biologically active sample to be maintained under fully hydrated and physiologically buffered conditions. The OEPs associated with PSII may be sequentially removed, thereby changing the surface of the complex by one polypeptide at a time.

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Imaging polymers, proteins and dna in aqueous solutions with the atomic force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152136 ◽

1989 ◽

Vol 47 ◽

pp. 32-33

Author(s):

S.A.C. Gould ◽

B. Drake ◽

C.B. Prater ◽

A.L. Weisenhorn ◽

S.M. Lindsay ◽

...

Keyword(s):

Amino Acids ◽

Dna Sequencing ◽

Aqueous Solutions ◽

Atomic Force Microscope ◽

Piezoelectric Crystal ◽

Atomic Force ◽

Structure Of Molecules ◽

Optical Lever

The atomic force microscope (AFM) is an instrument that can be used to image many samples of interest in biology and medicine. Images of polymerized amino acids, polyalanine and polyphenylalanine demonstrate the potential of the AFM for revealing the structure of molecules. Images of the protein fibrinogen which agree with TEM images demonstrate that the AFM can provide topographical data on larger molecules. Finally, images of DNA suggest the AFM may soon provide an easier and faster technique for DNA sequencing.The AFM consists of a microfabricated SiO2 triangular shaped cantilever with a diamond tip affixed at the elbow to act as a probe. The sample is mounted on a electronically driven piezoelectric crystal. It is then placed in contact with the tip and scanned. The topography of the surface causes minute deflections in the 100 μm long cantilever which are detected using an optical lever.

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The atomic-force microscope and its future in biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149350 ◽

1993 ◽

Vol 51 ◽

pp. 704-705

Author(s):

Jean-Paul Revel

Keyword(s):

Silicon Nitride ◽

Laser Beam ◽

Atomic Force Microscope ◽

Scanning Tunneling Microscope ◽

Point Of View ◽

Scanning Tunneling ◽

Close Relative ◽

Tunneling Microscope ◽

Atomic Force ◽

Sharp Point

The last few years have been marked by a series of remarkable developments in microscopy. Perhaps the most amazing of these is the growth of microscopies which use devices where the place of the lens has been taken by probes, which record information about the sample and display it in a spatial from the point of view of the context. From the point of view of the biologist one of the most promising of these microscopies without lenses is the scanned force microscope, aka atomic force microscope.This instrument was invented by Binnig, Quate and Gerber and is a close relative of the scanning tunneling microscope. Today's AFMs consist of a cantilever which bears a sharp point at its end. Often this is a silicon nitride pyramid, but there are many variations, the object of which is to make the tip sharper. A laser beam is directed at the back of the cantilever and is reflected into a split, or quadrant photodiode.

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