Integrated structuraland control design of a piezoelectric printhead for cell printing

The development of cell printing is vital for establishing bio-fabrication approaches as a tool of the organ transplantation and tissue regeneration. Though some cell printing experiments show the feasibility of this idea, however, undesired satellite droplets, nozzle clogging and cell damage in jetting process are still open issues that prevent the application of cell printing in engineering. To solve these problems, an integrated design of structural and control parameters of a piezoelectric drop-on-demand (DOD) printhead used for cell printing has been proposed. Based on the Computational-Fluid-Dynamics (CFD) model of the printhead, the desired droplet feature such as certain droplet speed and single droplet is obtained by optimizing the printhead dimensions and the control parameters, thus jetting failure and satellite droplets avoided. Moreover, the stress experienced by cells is reduced via minimizing pressure amplitude in the printhead. The results show that the optimized printhead can jet out highly viscous droplets with a desired speed and meanwhile the pressure amplitude is reduced by 15% as that it was, thus increasing the cell viability by 5.8%.