title: Elastic and viscoelastic characterization of microcapsules for drug delivery 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 at wet state during manipulation. The single-chip microgripper integrates an electrothermal microactuator and two capacitive force sensors, one for contact detection (force resolution: 38.5 nN) and the other for gripping force measurements (force resolution: 19.9 nN). With the capability of resolving gripping forces down to 19.9 nN and material deformations with a 20.5 nm resolution, the system quantified Young's modulus values and viscoelastic parameters of alginate microcapsules (15-25 microm), demonstrating an easy-to-operate, accurate compression testing technique for characterizing soft, micrometer-sized biomaterials.
authors.affiliation: Advanced Micro and Nanosystems Laboratory, University of Toronto, 5 King's College Road, Toronto, Ontario M5S3G8, Canada.
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
authors.initials: X
authors.lastname: Yu Wu
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
mesh_terms: D002214:Capsules / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D004353:Drug Evaluation, Preclinical / Q000295:instrumentation* / Q000379:methods; D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005246:Feedback; D006245:Hardness Tests / Q000295:instrumentation* / Q000379:methods; D008422:Materials Testing / Q000295:instrumentation*; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D013678:Technology, Pharmaceutical / Q000295:instrumentation / Q000379:methods; D014783:Viscosity
chemical_list: D002214:Capsules; D004337:Drug Carriers