Local plasma membrane permeabilization of living cells by nanosecond electric pulses using atomic force microscopy

AbstractOver the last decade, nanoneedle-based systems have demonstrated to be extremely useful in cell biology. They can be used as nanotools for drug delivery, biosensing or biomolecular recognition inside cells; or they can be employed to select and sort in parallel a large number of living cells. When using these nanoprobes, the most important requirement is to minimize the cell damage, reducing the forces and indentation lengths needed to penetrate the cell membrane. This is normally achieved by reducing the diameter of the nanoneedles. However, several studies have shown that nanoneedles with a flat tip display lower penetration forces and indentation lengths. In this work, we have tested different nanoneedle shapes and diameters to reduce the force and the indentation length needed to penetrate the cell membrane, demonstrating that ultra-thin and sharp nanoprobes can further reduce them, consequently minimizing the cell damage.

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Anisotropic Mechanical Properties of Living Cells Revealed by Integrated Spinning Disk Confocal and Atomic Force Microscopy

Biophysical Journal ◽

10.1016/j.bpj.2017.11.2803 ◽

2018 ◽

Vol 114 (3) ◽

pp. 513a

Author(s):

Yuri M. Efremov ◽

Mirian Velay-Lizancos ◽

Daniel M. Suter ◽

Pablo D. Zavattieri ◽

Arvind Raman

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Living Cells ◽

Force Microscopy ◽

Atomic Force ◽

Spinning Disk ◽

Anisotropic Mechanical Properties

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Imaging of Xenopus laevis Oocyte Plasma Membrane in Physiological-Like Conditions by Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927613001682 ◽

2013 ◽

Vol 19 (5) ◽

pp. 1358-1363 ◽

Cited By ~ 3

Author(s):

Massimo Santacroce ◽

Federica Daniele ◽

Andrea Cremona ◽

Diletta Scaccabarozzi ◽

Michela Castagna ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Plasma Membrane ◽

High Resolution ◽

Membrane Proteins ◽

Xenopus Laevis ◽

Functional Study ◽

Xenopus Laevis Oocyte ◽

Force Microscopy ◽

Atomic Force ◽

Afm Imaging

AbstractXenopus laevis oocytes are an interesting model for the study of many developmental mechanisms because of their dimensions and the ease with which they can be manipulated. In addition, they are widely employed systems for the expression and functional study of heterologous proteins, which can be expressed with high efficiency on their plasma membrane. Here we applied atomic force microscopy (AFM) to the study of the plasma membrane of X. laevis oocytes. In particular, we developed and optimized a new sample preparation protocol, based on the purification of plasma membranes by ultracentrifugation on a sucrose gradient, to perform a high-resolution AFM imaging of X. laevis oocyte plasma membrane in physiological-like conditions. Reproducible AFM topographs allowed visualization and dimensional characterization of membrane patches, whose height corresponds to a single lipid bilayer, as well as the presence of nanometer structures embedded in the plasma membrane and identified as native membrane proteins. The described method appears to be an applicable tool for performing high-resolution AFM imaging of X. laevis oocyte plasma membrane in a physiological-like environment, thus opening promising perspectives for studying in situ cloned membrane proteins of relevant biomedical/pharmacological interest expressed in this biological system.

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