Stand-alone microfluidic system using partly disposable PDMS microwell array for high throughput cell analysis

This paper presents a stand-alone microfluidic system composed of a reusable valve control part and a disposable microwell-array-embedded fluidic chip for high throughput cell analysis. The valve control part and the fluidic chip are fabricated separately and combined together in experiments. Since valve control of the device and fluid injection are driven by solenoid actuators and electro-osmosis (EO) micropumps, respectively, access-tube-free system is achieved. Utilization of addressable valve control method makes possible to drive 25 on-chip hydraulic valves by 10 solenoid actuators. The prototype fluidic chip with 16 microwell array and 4 reagent injection ports on top of palm-top size substrate (30 × 40 mm) is fabricated and integrated to make a replacement of multi-kind reagents inside the system. With this system, other functional fluidic networks can be replaced easily. After testing on/off switching performances of on-chip valves, multi-reagent exchange trial is carried out, revealing precise reagent injection of ten-nanoliter order to each microwell. The proposed system also shows high performance of power consumption, realizing introduction of two reagents to 16 microwells with 11.9 Wh.