Atomic force acoustic microscopy reveals the influence of substrate stiffness and topography on cell behavior

The stiffness and the topography of the substrate at the cell–substrate interface are two key properties influencing cell behavior. In this paper, atomic force acoustic microscopy (AFAM) is used to investigate the influence of substrate stiffness and substrate topography on the responses of L929 fibroblasts. This combined nondestructive technique is able to characterize materials at high lateral resolution. To produce substrates of tunable stiffness and topography, we imprint nanostripe patterns on undeveloped and developed SU-8 photoresist films using electron-beam lithography (EBL). Elastic deformations of the substrate surfaces and the cells are revealed by AFAM. Our results show that AFAM is capable of imaging surface elastic deformations. By immunofluorescence experiments, we find that the L929 cells significantly elongate on the patterned stiffness substrate, whereas the elasticity of the pattern has only little effect on the spreading of the L929 cells. The influence of the topography pattern on the cell alignment and morphology is even more pronounced leading to an arrangement of the cells along the nanostripe pattern. Our method is useful for the quantitative characterization of cell–substrate interactions and provides guidance for the tissue regeneration therapy in biomedicine.

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Influence of substrate stiffness on cell–substrate interfacial adhesion and spreading: A mechano-chemical coupling model

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2010.12.055 ◽

2011 ◽

Vol 355 (2) ◽

pp. 503-508 ◽

Cited By ~ 22

Author(s):

Jianyong Huang ◽

Xiaoling Peng ◽

Chunyang Xiong ◽

Jing Fang

Keyword(s):

Interfacial Adhesion ◽

Coupling Model ◽

Substrate Stiffness ◽

Cell Substrate ◽

Chemical Coupling ◽

Influence Of Substrate

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Nonlinear Cellular Mechanical Behavior Adaptation to Substrate Mechanics Identified by Atomic Force Microscope

International Journal of Molecular Sciences ◽

10.3390/ijms19113461 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3461 ◽

Cited By ~ 10

Author(s):

Keyvan Mollaeian ◽

Yi Liu ◽

Siyu Bi ◽

Yifei Wang ◽

Juan Ren ◽

...

Keyword(s):

Mechanical Properties ◽

Actin Cytoskeleton ◽

Cell Mechanics ◽

Living Cells ◽

Substrate Stiffness ◽

Adherent Cell ◽

Biomechanical Behavior ◽

Atomic Force ◽

Cell Substrate ◽

And Function

Cell–substrate interaction plays an important role in intracellular behavior and function. Adherent cell mechanics is directly regulated by the substrate mechanics. However, previous studies on the effect of substrate mechanics only focused on the stiffness relation between the substrate and the cells, and how the substrate stiffness affects the time-scale and length-scale of the cell mechanics has not yet been studied. The absence of this information directly limits the in-depth understanding of the cellular mechanotransduction process. In this study, the effect of substrate mechanics on the nonlinear biomechanical behavior of living cells was investigated using indentation-based atomic force microscopy. The mechanical properties and their nonlinearities of the cells cultured on four substrates with distinct mechanical properties were thoroughly investigated. Furthermore, the actin filament (F-actin) cytoskeleton of the cells was fluorescently stained to investigate the adaptation of F-actin cytoskeleton structure to the substrate mechanics. It was found that living cells sense and adapt to substrate mechanics: the cellular Young’s modulus, shear modulus, apparent viscosity, and their nonlinearities (mechanical property vs. measurement depth relation) were adapted to the substrates’ nonlinear mechanics. Moreover, the positive correlation between the cellular poroelasticity and the indentation remained the same regardless of the substrate stiffness nonlinearity, but was indeed more pronounced for the cells seeded on the softer substrates. Comparison of the F-actin cytoskeleton morphology confirmed that the substrate affects the cell mechanics by regulating the intracellular structure.

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Influence of Substrate Stiffness and Thickness and Anisotropic Cell Traction Forces on Cell Behavior

Biophysical Journal ◽

10.1016/j.bpj.2012.11.2647 ◽

2013 ◽

Vol 104 (2) ◽

pp. 479a

Author(s):

Srikanth Raghavan ◽

Aravind R. Rammohan ◽

Martial Hervy ◽

Magadalena Stolarska

Keyword(s):

Substrate Stiffness ◽

Cell Behavior ◽

Traction Forces ◽

Cell Traction Forces ◽

Cell Traction ◽

Influence Of Substrate

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Backside Application of Acoustic Micro Imaging (AMI) on Plastic Ball Grid Array (PBGA) and Plastic Quad Flat Pack (PQFP) Packages

ISTFA 2004: Conference Proceedings from the 30th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2004p0389 ◽

2004 ◽

Author(s):

Luis A. Curiel ◽

Andrew J. Komrowski ◽

Daniel J.D. Sullivan

Keyword(s):

Ball Grid Array ◽

Acoustic Microscopy ◽

Electronic Packages ◽

Nondestructive Technique ◽

Molding Compound ◽

Microscopy Technique ◽

Plastic Ball ◽

Die Surface ◽

Plastic Ball Grid Array ◽

Bond Pads

Abstract Acoustic Micro Imaging (AMI) is an established nondestructive technique for evaluation of electronic packages. Non-destructive evaluation of electronic packages is often a critical first step in the Failure Analysis (FA) process of semiconductor devices [1]. The molding compound to die surface interface of the Plastic Ball Grid Array (PBGA) and Plastic Quad Flat Pack (PQFP) packages is an important interface to acquire for the FA process. Occasionally, with these packages, the standard acoustic microscopy technique fails to identify defects at the molding compound to die surface interface. The hard to identify defects are found at the edge of the die next to the bond pads or under the bonds wires. This paper will present a technique, Backside Acoustic Micro Imaging (BAMI) analysis, which can better resolve the molding compound to die surface interface at the die edge by sending the acoustic signal through the backside of the PBGA and PQFP packages.

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Atomic force acoustic microscopy characterization of carbon-based materials

10.3728/icultrasonics.2007.vienna.1650_passeri ◽

2007 ◽

Author(s):

D. Passeri ◽

A. Bettucci ◽

M. Germano ◽

A. Biagioni ◽

M. Rossi ◽

...

Keyword(s):

Acoustic Microscopy ◽

Atomic Force ◽

Microscopy Characterization ◽

Carbon Based

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Measurement of the Indentation Modulus and the Local Internal Friction in Amorphous SiO2 Using Atomic Force Acoustic Microscopy

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0006 ◽

2016 ◽

Vol 61 (1) ◽

pp. 9-12

Author(s):

B. Zhang ◽

H. Wagner ◽

M. Büchsenschütz-Göbeler ◽

Y. Luo ◽

S. Küchemann ◽

...

Keyword(s):

Internal Friction ◽

Amorphous Materials ◽

Contact Stiffness ◽

Ultrasonic Transducer ◽

Amorphous Material ◽

Acoustic Microscopy ◽

Damping Factor ◽

Indentation Modulus ◽

Amorphous Sio2 ◽

Atomic Force

Abstract For the past two decades, atomic force acoustic microscopy (AFAM), an advanced scanning probe microscopy technique, has played a promising role in materials characterization with a good lateral resolution at micro/nano dimensions. AFAM is based on inducing out-of-plane vibrations in the specimen, which are generated by an ultrasonic transducer. The vibrations are sensed by the AFM cantilever when its tip is in contact with the material under test. From the cantilver’s contactresonance spectra, one determines the real and the imaginary part of the contact stiffness k*, and then from these two quantities the local indentation modulus M' and the local damping factor Qloc-1 can be obtained with a spatial resolution of less than 10 nm. Here, we present measured data of M' and of Qloc-1 for the insulating amorphous material, a-SiO2. The amorphous SiO2 layer was prepared on a crystalline Si wafer by means of thermal oxidation. There is a spatial distribution of the indentation modulus M' and of the internal friction Qloc-1. This is a consequence of the potential energy landscape for amorphous materials.

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