UC Irvine

It is essential to study the biomechanics of cardiomyocytes in vitro in order to develop drugs and diagnostic tools to treat cardiovascular diseases. Here a grooved and pegged micro-cantilever to observe and quantify the contractile behavior of cardiomyocytes was developed. The platform was based on muscular thin films technologies; however, this platform presents some unique features.

The aim of the project was to develop a simple platform to measure the amount of cantilever deformation as the shape and degree of the cantilever bending under stress can then be used to quantify the contractility of the cells. The end result is a micro-cantilever platform that can be used to study cardiomyocytes and their responses to various drugs.

The micro-cantilever contains pegs and grooves that cause the cardiomyoctes grown on the platform such that it mimics the anisotropic structure of native cardiac tissue. Two sets of micro-platforms were fabricated out of two different materials: poly(dimethylsiloxane) (PDMS) and SU-8 photoresist. SU-8 and PDMS are both biocompatible and have their own advantages and disadvantages. The SU-8 micro-platforms were fabricated using multilayer photolithography while the PDMS micro-cantilevers were fabricated using multilayer soft lithography. HL-1 cardiomyocytes were then cultured on to SU-8 substrates and primary neonatal rat cardiomyocytes were cultured onto PDMS cantilevers. Concurrently, finite element analysis was performed in order to determine the dimensions that caused the most cantilever deflection.