title: Mechanical characterization of polymeric microcapsules using a force-feedback MEMS microgripper.
abstract: This paper reports a monolithic, force-feedback MEMS (microelectomechanical systems) microgripper and its application to micro-scale compression testing of swollen hydrogel microcapsules during manipulation in an aqueous environment. The single-chip microgripper uses an electrothermal microactuator for grasping and integrates two capacitive force sensors, one for contact detection (force resolution: 38.5nN) and the other for gripping force measurements (force resolution: 19.9nN). Using the force-feedback microgripper and a mechanics model for assessing large deformation data, the system with a 19.9nN force resolution and a 20.5nm resolution for material deformation measurement quantified Young's modulus values of individual alginate microcapsules (15-25microm) with 1%, 2%, and 3% chitosan coating, demonstrating an easy-to-operate, accurate compression testing technique for mechanically characterizing soft, micrometer-sized biomaterials.
authors.affiliation: Advanced Micro and Nanosystems Laboratory, University of Toronto, 5 King¿s College Road, ON, Canada, M5S 3G8.
authors.forename: Keekyoung
authors.initials: K
authors.lastname: Kim
authors.forename: Xinyu
authors.initials: X
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ji
authors.initials: J
authors.lastname: Cheng
authors.forename: Xiao Yu
authors.initials: XY
authors.lastname: Wu
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
mesh_terms: D001672:Biocompatible Materials; D001696:Biomechanical Phenomena; D001698:Biomedical Engineering / Q000295:instrumentation; D002214:Capsules; D048271:Chitosan; D019245:Compressive Strength; D004867:Equipment Design; D008422:Materials Testing; D011108:Polymers; D014867:Water
chemical_list: D001672:Biocompatible Materials; D002214:Capsules; D011108:Polymers; D014867:Water; D048271:Chitosan