A microfabricated microcantilever array: A platform for investigation of cellular biomechanics and microforces in vitro

Abstract

Living cells and tissues experience mechanical forces in their physiological environments that are known to affect many cellular processes. Also of importance are the mechanical properties of cells, as well as the microforces generated by cellular processes in their microenvironments. The difficulty associated with studying these phenomena in vivo has led to alternatives such as using in vitro models. The need for experimental techniques for investigating cellular biomechanics and mechanobiology in vitro has fueled an evolution in the technology used in these studies. Particularly noteworthy are some of the new biomicroelectromechanical systems (BioMEMs) devices and techniques.

This study describes cellular micromechanical techniques and methods that have been developed for extit{in vitro} studies. Improvements made to a passive array of vertical microcantilevers, for detecting cellular microforces and studying in vitro cell mechanics are presented. A new technique that uses poly(vinyl alcohol) (PVA) as a lift-off agent to attach structures to the microcantilevers, thereby providing a means to actively move the microcantilevers is introduced. The use of the improved microcantilever array platform as a potential assay for cardiac myofibrillogenesis will also be described.

Finally the use of cryogenic etching techniques for making master molds for the microcantilever arrays is described, and subsequent arrays are used to investigate the biological responses of mesenchymal stem cells to forces generated by post deflections.