Automated AFM force curve analysis for determining elastic modulus of biomaterials and biological samples

被引:48
作者
Chang, Yow-Ren [1 ]
Raghunathan, Vijay Krishna [1 ]
Garland, Shaun P. [2 ]
Morgan, Joshua T. [1 ]
Russell, Paul [1 ]
Murphy, Christopher J. [1 ,3 ]
机构
[1] Univ Calif Davis, Sch Vet Med, Dept Surg & Radiol Sci, Davis, CA 95616 USA
[2] Univ Calif Davis, Dept Biomed Engn, Davis, CA 95616 USA
[3] Univ Calif Davis, Sch Med, Dept Ophthalmol & Vis Sci, Davis, CA 95616 USA
关键词
Atomic force microscopy; Contact point; Elastic modulus; Nano-indentation; Biomechanics; CONTACT POINT; ROBUST STRATEGIES; CELL STIFFNESS; THIN-LAYERS; MICROSCOPE; INDENTATION; SUBSTRATE; SOFT; SPECTROSCOPY; HYDROGELS;
D O I
10.1016/j.jmbbm.2014.05.027
中图分类号
R318 [生物医学工程];
学科分类号
0831 ;
摘要
The analysis of atomic force microscopy (AFM) force data requires the selection of a contact point (CP) and is often time consuming and subjective due to influence from intermolecular forces and low signal-to-noise ratios (SNR). In this report, we present an automated algorithm for the selection of CPs in AFM force data and the evaluation of elastic moduli. We propose that CP may be algorithmically easier to detect by identifying a linear elastic indentation region of data (high SNR) rather than the contact point itself (low SNR). Utilizing Hertzian mechanics, the data are fitted for the CP. We first detail the algorithm and then evaluate it on sample polymeric and biological materials. As a demonstration of automation, 64 x 64 force maps were analyzed to yield spatially varying topographical and mechanical information of cells. Finally, we compared manually selected CPs to automatically identified CPs and demonstrated that our automated approach is both accurate (< 10 nm difference between manual and automatic) and precise for non-interacting polymeric materials. Our data show that the algorithm is useful for analysis of both biomaterials and biological samples. (C) 2014 Elsevier Ltd. All rights reserved.
引用
收藏
页码:209 / 218
页数:10
相关论文
共 39 条
[1]   Mechanical properties of hydrogels and their experimental determination [J].
Anseth, KS ;
Bowman, CN ;
BrannonPeppas, L .
BIOMATERIALS, 1996, 17 (17) :1647-1657
[2]   A new automatic contact point detection algorithm for AFM force curves [J].
Benitez, Rafael ;
Moreno-flores, Susana ;
Bolos, Vicente J. ;
Luis Toca-Herrera, Jose .
MICROSCOPY RESEARCH AND TECHNIQUE, 2013, 76 (08) :870-876
[3]   ATOMIC FORCE MICROSCOPE [J].
BINNIG, G ;
QUATE, CF ;
GERBER, C .
PHYSICAL REVIEW LETTERS, 1986, 56 (09) :930-933
[4]   Assessing micromechanical properties of cells with atomic force microscopy: importance of the contact point [J].
Crick, S. L. ;
Yin, F. C. -P. .
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY, 2007, 6 (03) :199-210
[5]   EFFECT OF CONTACT DEFORMATIONS ON ADHESION OF PARTICLES [J].
DERJAGUIN, BV ;
MULLER, VM ;
TOPOROV, YP .
JOURNAL OF COLLOID AND INTERFACE SCIENCE, 1975, 53 (02) :314-326
[6]   Determination of elastic moduli of thin layers of soft material using the atomic force microscope [J].
Dimitriadis, EK ;
Horkay, F ;
Maresca, J ;
Kachar, B ;
Chadwick, RS .
BIOPHYSICAL JOURNAL, 2002, 82 (05) :2798-2810
[7]   Tissue cells feel and respond to the stiffness of their substrate [J].
Discher, DE ;
Janmey, P ;
Wang, YL .
SCIENCE, 2005, 310 (5751) :1139-1143
[8]  
Dufrêne YF, 2013, NAT METHODS, V10, P847, DOI [10.1038/NMETH.2602, 10.1038/nmeth.2602]
[9]   Matrix elasticity directs stem cell lineage specification [J].
Engler, Adam J. ;
Sen, Shamik ;
Sweeney, H. Lee ;
Discher, Dennis E. .
CELL, 2006, 126 (04) :677-689
[10]   Spatially resolved force spectroscopy of bacterial surfaces using force-volume imaging [J].
Gaboriaud, Fabien ;
Parcha, Bhargava S. ;
Gee, Michelle L. ;
Holden, James A. ;
Strugnell, Richard A. .
COLLOIDS AND SURFACES B-BIOINTERFACES, 2008, 62 (02) :206-213