Next-Generation Microfluidic Devices for Accurate and Rapid Biomarker Separation from Whole Blood

We develop lab-on-a-chip devices using microfluidics, focusing on deterministic lateral displacement (DLD) technology, for the efficient isolation of disease biomarkers such as extracellular vesicles from blood. In DLD, particles are separated based on their diameter, with larger particles being displaced laterally and smaller ones following a zigzag path as they pass through an array of obstacles. We fabricated various DLD structures on silicon wafers, using e-beam lithography and a maskless aligner to create silicon nanopost arrays with diameters of 300-600 nm and critical diameters of 100-350 nm. Inlet and outlet ports were added to the top transparent silica wafer using drilling techniques, and the wafer was bonded to the DLD devices via anodic bonding. Initial tests with small fluorescent particles (< critical size) showed that they traveled through the DLD array in zigzag mode, as predicted, with results aligning with finite element modeling and analysis. Research presented in this paper was supported by the National Science Foundation under NSF EPSCoR Track-1 Cooperative Agreement OIA #1946202. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the NSF.