Integrated siphon-based metering and sedimentation of whole blood on a hydrophilic lab-on-a-disk

Abstract  In this paper, we present a novel and fully integrated centrifugal microfluidic “lab-on-a-disk” for rapid colorimetric assays in human whole blood. All essential steps comprising blood sampling, metering, plasma extraction and the final optical detection are conducted within t = 150 s in passive, globally hydrophilized structures which obviate the need for intricate local hydrophobic surface patterning. Our technology features a plasma extraction structure (V = 500 nL, CV < 5%) where the purified plasma (c RBC < 0.11%) is centrifugally separated, metered by an overflow and subsequently extracted by a siphon-based principle through a hydrophilic extraction channel into the detection chamber.