title: Capsule-substrate contact deformation: determination of adhesion energy.
abstract: A study is reported of a cellular entity (liquid-filled microcapsule) adhered on a flat glass substrate in response to changes in osmotic pressure and temperature. High-resolution reflection interference contrast microscopy (HR-RICM) and phase-contrast microscopy were developed for probing the adhesion contact area, capsule-substrate separation profile and adhesion energy of the adhering microcapsule. The new technique increased the detection limit of the measured capsule wall-substrate separation in the cohesive zone from 1 to 4.5 microm and improved the spatial resolution of the heterogeneous contact zones. A theoretical model was applied to correlate quantitatively the adhesion energy to the area of the contact zone. The work demonstrated the possibility of ascertaining the quantitative interfacial adhesion energy of a liquid-filled microcapsule using the present technique and represents the first step in extending this novel approach to study more complicated systems, such as cell-substrate interactions, in the future.
authors.affiliation: Tissue Engineering Laboratory, School of Mechanical Production Engineering, Nanyang Technological University, Singapore. mkkliu@ntu.edu.sg
authors.forename: K K
authors.initials: KK
authors.lastname: Liu
authors.forename: V
authors.initials: V
authors.lastname: Chan
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002214:Capsules; D002448:Cell Adhesion; D018613:Microscopy, Confocal; D008858:Microscopy, Phase-Contrast; D008954:Models, Biological; D009997:Osmotic Pressure
chemical_list: D002214:Capsules