Investigation of Adhesion and Mechanical Properties of Human Glioma Cells by Single Cell Force Spectroscopy and Atomic Force Microscopy

Atomic force microscopy is a valuable and useful tool for the imaging and investigation of living cells in their natural environment at high resolution. Procedures applied to living cell preparation before measurements should be adapted individually for different kinds of cells and for the desired measurement technique. Different ways of cell immobilization, such as chemical fixation on the surface, entrapment in the pores of a membrane, or growing them directly on glass cover slips or on plastic substrates, result in the distortion or appearance of artifacts in atomic force microscopy images. Cell fixation allows the multiple use of samples and storage for a prolonged period; it also increases the resolution of imaging. Different atomic force microscopy modes are used for the imaging and analysis of living cells. The contact mode is the best for cell imaging because of high resolution, but it is usually based on the following: (i) image formation at low interaction force, (ii) low scanning speed, and (iii) usage of “soft,” low resolution cantilevers. The tapping mode allows a cell to behave like a very solid material, and destructive shear forces are minimized, but imaging in liquid is difficult. The force spectroscopy mode is used for measuring the mechanical properties of cells; however, obtained results strongly depend on the cell fixation method. In this paper, the application of 3 atomic force microscopy modes including (i) contact, (ii) tapping, and (iii) force spectroscopy for the investigation of cells is described. The possibilities of cell preparation for the measurements, imaging, and determination of mechanical properties of cells are provided. The applicability of atomic force microscopy to diagnostics and other biomedical purposes is discussed.

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Quantifying the Effect of Anti-cancer Compound (Piperlongumine) on Cancer Cells Using Single-Cell Force Spectroscopy

10.1101/2021.09.03.458840 ◽

2021 ◽

Author(s):

Nayara Sousa de Alcântara-Contessoto ◽

Marinônio Lopes Cornélio ◽

Ching-Hwa Kiang

Keyword(s):

Mechanical Properties ◽

Single Cell ◽

Hela Cells ◽

Cell Manipulation ◽

Tumor Growth Inhibition ◽

Force Microscopy ◽

Therapeutic Drugs ◽

Atomic Force ◽

Anti Cancer ◽

Cell Force

AbstractNatural compounds have shown a great potential in anti-cancer research by tumor growth inhibition and anti-metastatic properties. Piperlongumine (PL) is a natural compound derived from pepper species that has been demonstrated to have anti-cancer effect on HeLa cells. Here we focus on understanding the mechanical properties of HeLa cells under PL treatment, using Atomic Force Microscopy (AFM) based single-cell manipulation technique. We used AFM to pull single HeLa cells and acquired the force-distance curves that presented stepwise patterns. We analyzed the step force (SF) and observed that cells treated with PL exhibit higher force compared to control cells. This SF increase was also observed in experiments performed on substrates of different stiffness. Therefore, analyzing SF, it is possible to investigate the effect of PL on the mechanical properties of the HeLa cells. The understanding of the PL action on HeLa cells’ mechanical properties may help in the development of effective therapeutic drugs against cancers.

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Bioconjugation Strategies for Connecting Proteins to DNA-Linkers for Single-Molecule Force-Based Experiments

Nanomaterials ◽

10.3390/nano11092424 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2424

Author(s):

Lyan M. van der Sleen ◽

Katarzyna M. Tych

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Optical Tweezers ◽

Single Molecule ◽

Short Range ◽

Force Spectroscopy ◽

Magnetic Tweezers ◽

Single Molecule Force Spectroscopy ◽

Force Microscopy ◽

Atomic Force

The mechanical properties of proteins can be studied with single molecule force spectroscopy (SMFS) using optical tweezers, atomic force microscopy and magnetic tweezers. It is common to utilize a flexible linker between the protein and trapped probe to exclude short-range interactions in SMFS experiments. One of the most prevalent linkers is DNA due to its well-defined properties, although attachment strategies between the DNA linker and protein or probe may vary. We will therefore provide a general overview of the currently existing non-covalent and covalent bioconjugation strategies to site-specifically conjugate DNA-linkers to the protein of interest. In the search for a standardized conjugation strategy, considerations include their mechanical properties in the context of SMFS, feasibility of site-directed labeling, labeling efficiency, and costs.

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Concurrent Atomic Force Spectroscopy

10.1101/293506 ◽

2018 ◽

Author(s):

Carolina Pimenta-Lopes ◽

Carmen Suay-Corredera ◽

Diana Velázquez-Carreras ◽

David Sánchez-Ortiz ◽

Jorge Alegre-Cebollada

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Single Molecule ◽

Mechanical Characterization ◽

Force Spectroscopy ◽

Fold Increase ◽

Force Measurements ◽

Force Microscopy ◽

Atomic Force ◽

Calibration Uncertainty

ABSTRACTForce-spectroscopy by Atomic Force Microscopy (AFM) is the technique of choice to measure mechanical properties of molecules, cells, tissues and materials at the nano and micro scales. However, unavoidable calibration errors of AFM probes make it cumbersome to quantify modulation of mechanics. Here, we show that concurrent AFM force measurements enable relative mechanical characterization with an accuracy that is independent of calibration uncertainty, even when averaging data from multiple, independent experiments. Compared to traditional AFM, we estimate that concurrent strategies can measure differences in protein mechanical unfolding forces with a 6-fold improvement in accuracy and a 30-fold increase in throughput. Prompted by our results, we demonstrate widely applicable orthogonal fingerprinting strategies for concurrent single-molecule nanomechanical profiling of proteins.

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Gene Classification and Quantitative Analysis of Gene Regulation in Bacteria Using Single Cell Atomic Force Microscopy and Single Molecule Force Spectroscopy

Single Cell Analysis ◽

10.1002/9783527626649.ch2 ◽

2009 ◽

pp. 19-37

Author(s):

Robert Ros ◽

Nicole Hansmeier

Keyword(s):

Atomic Force Microscopy ◽

Gene Regulation ◽

Quantitative Analysis ◽

Single Cell ◽

Single Molecule ◽

Force Spectroscopy ◽

Single Molecule Force Spectroscopy ◽

Force Microscopy ◽

Atomic Force

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Macroscopic and microscopic analysis of the mechanical properties and adhesion force of cells using a single cell tensile test and atomic force microscopy: Remarkable differences in cell types

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2020.103935 ◽

2020 ◽

Vol 110 ◽

pp. 103935 ◽

Cited By ~ 2

Author(s):

Kazuaki Nagayama ◽

Shigeaki Ohata ◽

Shota Obata ◽

Akiko Sato

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Tensile Test ◽

Single Cell ◽

Adhesion Force ◽

Microscopic Analysis ◽

Cell Types ◽

Force Microscopy ◽

Atomic Force

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Mechanical Properties of Membrane Surface of Cultured Astrocyte Revealed by Atomic Force Microscopy

Japanese Journal of Applied Physics ◽

10.1143/jjap.39.3711 ◽

2000 ◽

Vol 39 (Part 1, No. 6B) ◽

pp. 3711-3716 ◽

Cited By ~ 15

Author(s):

Hatsuki Shiga ◽

Yukako Yamane ◽

Etsuro Ito ◽

Kazuhiro Abe ◽

Kazushige Kawabata ◽

...

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Membrane Surface ◽

Force Microscopy ◽

Atomic Force

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Corrosion Behavior and Mechanical Properties of a Nanocomposite Superhydrophobic Coating

Coatings ◽

10.3390/coatings11060652 ◽

2021 ◽

Vol 11 (6) ◽

pp. 652

Author(s):

Divine Sebastian ◽

Chun-Wei Yao ◽

Lutfun Nipa ◽

Ian Lian ◽

Gary Twu

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Atomic Force Microscopy ◽

Nanocomposite Coating ◽

Superhydrophobic Coating ◽

Force Microscopy ◽

Atomic Force ◽

Microscopy Images ◽

Scanning Electron

In this work, a mechanically durable anticorrosion superhydrophobic coating is developed using a nanocomposite coating solution composed of silica nanoparticles and epoxy resin. The nanocomposite coating developed was tested for its superhydrophobic behavior using goniometry; surface morphology using scanning electron microscopy and atomic force microscopy; elemental composition using energy dispersive X-ray spectroscopy; corrosion resistance using atomic force microscopy; and potentiodynamic polarization measurements. The nanocomposite coating possesses hierarchical micro/nanostructures, according to the scanning electron microscopy images, and the presence of such structures was further confirmed by the atomic force microscopy images. The developed nanocomposite coating was found to be highly superhydrophobic as well as corrosion resistant, according to the results from static contact angle measurement and potentiodynamic polarization measurement, respectively. The abrasion resistance and mechanical durability of the nanocomposite coating were studied by abrasion tests, and the mechanical properties such as reduced modulus and Berkovich hardness were evaluated with the aid of nanoindentation tests.

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