Bioreactors

The three-dimensional cardiac constructs developed in vitro require gas and nutrient supply through mass diffusion. In static bioreactor, there is no fluid mixing and cells in the center of construct do not receive enough nutrients and removal of waste. Thus, the cells will die. To improve mass transport, several bioreactors have been designed with dynamic capabilities. A basic dynamic bioreactor is a spinner flask, where the flask is agitated and the cell constructs have turbulently mixed fluid which allows for better diffusion and healthier cells. However, this type of turbulent flow is not ideal for cardiac cells. Bioreactors combined with mechanical signal stimuli improved proliferation and distribution of cells and formation and organization of extracellular matrix. Future bioreactors should combine perfusion and mechanical stimuli such as pulsatile flow and varying levels of pressure.