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Broad modulus range nanomechanical mapping by magnetic-drive soft probes.

ABSTRACT: Stiffness matching between the probe and deformed portion of the sample in piezo-drive peak force modulation atomic force microscopy (AFM) limits the modulus measurement range of single probes. Here we develop a magnetic drive peak force modulation AFM to broaden the dynamic range of the probe with direct cantilever excitation. This approach not only successfully drives the softest commercial probe (6?pN?nm-1) for mapping extremely soft samples in liquid but also provides an indentation force of hundreds of nanonewtons for stiff samples with a soft probe. Features of direct measurements of the indentation force and depth can unify the elastic modulus range up to four orders of magnitude, from 1?kPa to 10?MPa (in liquid) and 1?MPa to 20?GPa (in air or liquid) using a single probe. This approach can be particularly useful for analysing heterogeneous samples with large elastic modulus variations in multi-environments.

SUBMITTER: Meng X

PROVIDER: S-EPMC5717272 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Broad modulus range nanomechanical mapping by magnetic-drive soft probes.

Meng Xianghe X Zhang Hao H Song Jianmin J Fan Xinjian X Sun Lining L Xie Hui H

Nature communications 20171205 1

Stiffness matching between the probe and deformed portion of the sample in piezo-drive peak force modulation atomic force microscopy (AFM) limits the modulus measurement range of single probes. Here we develop a magnetic drive peak force modulation AFM to broaden the dynamic range of the probe with direct cantilever excitation. This approach not only successfully drives the softest commercial probe (6 pN nm<sup>-1</sup>) for mapping extremely soft samples in liquid but also provides an indentati ...[more]

PMID: 29208894

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Broad modulus range nanomechanical mapping by magnetic-drive soft probes.

Publications

Broad modulus range nanomechanical mapping by magnetic-drive soft probes.

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