Substrate viscosity plays an important role in bacterial adhesion under fluid flow

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:552

Article

Valentin, Jules D. P.^1,2,3  Qin, Xiao-Hua^1,4  Fessele, Claudia¹  Straub, Herve¹  van der Mei, Henny C.^2,3  Buhmann, Matthias T.¹  Maniura-Weber, Katharina¹  Ren, Qun¹ 

[1] Swiss Fed Labs Mat Sci & Technol, Empa, Lab Biointerfaces, Lerchenfeldstr 5, CH-9014 St Gallen, Switzerland

[2] Univ Groningen, Dept Biomed Engn FB40, Antonius Deusinglaan 1, NL-9713 AV Groningen, Netherlands

[3] Univ Med Ctr Groningen, Dept Biomed Engn FB40, Antonius Deusinglaan 1, NL-9713 AV Groningen, Netherlands

[4] Swiss Fed Inst Technol, Inst Biomech, Leopold Ruzicka Weg 4, CH-8093 Zurich, Switzerland

关键词: Viscoelasticity;    PDMS;    Stickiness;    Bacterial adhesion;    Bacterial retention force;   

DOI  :  10.1016/j.jcis.2019.05.043

来源: Elsevier

【 摘 要 】

Many materials used in the medical settings such as catheters and contact lenses as well as most biological tissues are not purely elastic, but rather viscoelastic. While substrate elasticity has been investigated for its influence on bacterial adhesion, the impact of substrate viscosity has not been explored. Here, the importance of considering substrate viscosity is explored by using polydimethylsiloxane (PDMS) as the substrate material, whose mechanical properties can be tuned from predominantly elastic to viscous by varying cross-linking degree. Interfacial rheology and atomic force microscopy analysis prove that PDMS with a low cross-linking degree exhibits both low stiffness and high viscosity. This degree of viscoelasticity confers to PDMS a remarkable stress relaxation, a good capability to deform and an increased adhesive force. Bacterial adhesion assays were conducted under flow conditions to study the impact of substrate viscosity on Escherichia coli adhesion. The viscous PDMS not only enhanced E. coli adhesion but also conferred greater resistance to desorption against shear stress at air/liquid interface, compared to the PDMS with high crosslinking degree. These findings highlight the importance to consider substrate viscosity while studying bacterial adhesion. The current work provides new insights to an improved understanding of how bacteria interact with complex viscoelastic environments. (C) 2019 The Authors. Published by Elsevier Inc.

【 授权许可】

Free