期刊
MICROSCOPY RESEARCH AND TECHNIQUE
卷 69, 期 2, 页码 84-92出版社
WILEY
DOI: 10.1002/jemt.20275
关键词
indentation; mechanical properties; Young's modulus
A homemade colloidal probe atomic force microscope was used to perform nanoindentation with a spherical probe of 5 pm in diameter, at different approach velocities in order to extract the Young's modulus, E-0, of poly(L-lysine)/hyaluronan (PLL/HA) films. This parameter is of prime importance to control cellular adhesion. The films were either kept in their native form or cross-linked with a mixture of 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide (EDC) and N-hydrosulfosuccinimide (sulfo-NHS), where the EDC concentration was varied from 1 up to 100 mg mL(-1) (approximately from 5 to 500 mM). A model based on Hertz mechanics was used to account for the interactions between film and probe. It is shown that the Young's modulus varies with the approach velocity for the native (PLL/HA) films, whereas for cross-linked ones, E-0 is independent from the velocity over the whole range investigated. It is found that for native films, E-0 takes a value of 3 kPa at low approach velocities, a velocity domain that should be relevant in cellular adhesion processes. The Young's modulus increases with the EDC concentration used to cross-link the films and levels off at a value of about 400 kPa for EDC concentrations exceeding 40 mg mL-1. Thus, it is possible by crosslinking PLL/HA films to control their elastic properties with the aim to alter their behavior as to the cellular adhesion.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据