Microdevice for plasma separation from whole human blood using bio-physical and geometrical effects

TLDR

The device builds on extensive experimental studies of blood flow and separation in microchannels. The study introduces a simple, passive microfluidic device for efficient plasma separation from whole human blood. Fabricated by conventional photolithography on a single‑layer PDMS chip with ~100 µm channels, the device operates clog‑free and its plasma output is characterized by UV spectrophotometry, hCG, glucose, and flow cytometry. The device achieves nearly 100 % separation efficiency at 0.3–0.5 ml min⁻¹, works up to 62 % hematocrit, delivers high‑quality plasma, and is compact, economical, and suitable for continuous flow.

Abstract

Abstract In this research work, we present a simple and efficient passive microfluidic device for plasma separation from pure blood. The microdevice has been fabricated using conventional photolithography technique on a single layer of polydimethylsiloxane, and has been extensively tested on whole blood and enhanced (upto 62%) hematocrit levels of human blood. The microdevice employs elevated dimensions of about 100 μm; such elevated dimensions ensure clog-free operation of the microdevice and is relatively easy to fabricate. We show that our microdevice achieves almost 100% separation efficiency on undiluted blood in the flow rate range of 0.3 to 0.5 ml/min. Detailed biological characterization of the plasma obtained from the microdevice is carried out by testing: proteins by ultra-violet spectrophotometric method, hCG (human chorionic gonadotropin) hormone, and conducting random blood glucose test. Additionally, flow cytometry study has also been carried on the separated plasma. These tests attest to the high quality of plasma recovered. The microdevice developed in this work is an outcome of extensive experimental research on understanding the flow behavior and separation phenomenon of blood in microchannels. The microdevice is compact, economical and effective, and is particularly suited in continuous flow operations.