Development and customization of a concentration gradient microgenerator by extrusion 3D printing for drug testing in laboratory studies

A crucial step in creating reliable in vitro high-throughput screening technology platforms for the effect of pharmaceutical/chemical studies is the development of microfluidic systems. The power of concentration gradient generators in microfluidic systems could be harnessed to rapidly screen and investigate the mechanisms underlying the effects of pharmaceutical or chemical compounds on various disease models. A challenge of the current concentration gradient generator is the difficulty of fabricating them by common research laboratories. In order to overcome this challenge, additive manufacturing process as 3D printing can be utilized to produce customizable complex 3D structures using a layer-by-layer process. We developed a concentration gradient generator 3D printed on a tissue culture plate as a simplified strategy for in vitro pharmaceutical/chemical testing. The bottom layers used to print the concentration gradient microgenerators are regular culture plates used in common research laboratories. A Christmas tree-like network microfluidic channel was printed on the culture plate and generate a concentration gradient flow. The microfluidic network was printed on culture plates made from different cell culture plastic materials. The printed gradient generator was validated for drug testing function on cells. Our 3D printed concentration gradient microgenerators could provide a simplified strategy for common research laboratories to access microfluidic in vitro drug high-throughput screening technology.