Microdfluidic based 3-dimensional cell culture platform

This study reports a new perfusion-based, micro threedimensional (3-D) cell culture platform for drug testing using enabling microfluidic technologies. In this work, a perfusionbased, micro 3-D cell culture platform is designed and is fabricated based on SU-8 lithography and polydimethylsiloxane (PDMS) replication processes. One of the key features of the system is that the incorporation of a multiple medium pumping mechanism, consisting of 15 membranebased pneumatic micropumps with serpentine-shape (S-shape) layout, coupled with a pneumatic tank, into the micro 3-D cell culture platform to provide efficient and economical culture medium delivery. Moreover, a "smart cell/agarose (scaffold) loading mechanism" was proposed, allowing the cell/3-D scaffold loading process in one step and avoiding too much laborious works and manual error. The results show that in all of the 15 S-shape pneumatic micropumps studied, the medium delivery mechanism is able to provide a uniform flow output ranging from 5.5 to 131 μl/hr depending on the applied pulsation frequency of the micropumps. In addition, the cell/agarose (scaffold) loading mechanism was proved to be able to perform sample loading tasks precisely and accurately in all of the 15 microbioreactors integrated. Furthermore, anticancer drug testing was successfully demonstrated using the proposed culture platform and fluorescent microscopic observation. As a whole, because of miniaturization, not only does this perfusion 3-D cell culture platform provide a homogenous and steady cell culture environment, but it also reduces the need for human intervention. Moreover, due to the integrated pumping of the medium and the cell/agarose (scaffold) loading mechanisms, time efficient and economical research work can be achieved. These characteristics are found particularly useful for high-precision and high-throughput 3-D cell culture-based drug testing.