Runway-shaped microchannel with flow rate insensitivity for high-throughput blood plasma extraction

Abstract

Conventional inertial microfluidic devices are plagued by a low throughput, sheath fluid dependency, and constrained operational flow rate range during plasma extraction processes. Thus, a runway-shaped inertial microfluidic device for continuous blood plasma extraction has been proposed. By integrating curved channels with semicircular obstacles into the CEA channels, the device can generate stable and enhanced Dean vortices in each loop of the channel without the need for sheath fluid assistance. This configuration effectively promoted the rapid formation of steady focusing states for particles of different diameters (5, 10, and 15 μm). The device demonstrated remarkable flow rate insensitivity (0.2 to 1.7 mL/min) for blood cell focusing, enabling plasma extraction across a wide flow rate range. For 1 % hematocrit blood sample operated at a flow rate of 1.4 mL/min, the plasma collected from outlet 3 showed a 1528-fold reduction in blood cell concentration, and the blood cell rejection efficiency reached 99.93 %. These results confirmed that the device is capable of extracting highly purified blood plasma with the advantages of simple operation, insensitivity to flow rates, and high throughput. The device is also expected to provide a favorable opportunity for the preparation and analysis of blood samples for disease diagnosis.