Engineering a vacuum-actuated peristaltic micropump with novel microchannel design to rapidly separate blood plasma with extremely low hemolysis

A need exists for scalable, automated lab-on-chip systems to separate blood plasma for medical diagnostics. In this study, a vacuum-actuated peristaltic micropump (VPM) was developed, incorporating with the inertial microfluidic technique for the separation and collection of blood plasma from diluted blood. The features of the micropump were investigated by varying parameters such as frequency, vacuum pressure, and the number of microchannels. The highest achievable flow rate was found to be 832 µL/min. Subsequently, to minimize the occurrence of red blood cell rupture during the separation process and significantly reduce hemolysis, the configuration of the vertical wall inside the microchannel was modified to an inclined wall. This improvement was validated through experiments using high-speed cameras and fluorescent particles. Blood plasma separation was achieved with high efficiency (98.5 %), rapidity (<1 min), automation, and minimal whole blood usage (5 µL). Importantly, the vacuum actuator with an inclined wall obstruction design demonstrated very low hemolysis (less than 2 %).