Development of microfluidic chip for dilation of slurry

Abstract

In this paper, we propose a novel design of channels for dilution of microfluidic samples having suspended particles without the use of a secondary buffer solution. The proposed design takes advantage of parallelization to augment the sample processing rate while maintaining a similar dilation performance. Seven different microchannel geometries are tested to identify the most efficient design. The dilation performance and service life have been substantially increased by using improvised design, in which microchannels are connected between headers, and a circular pillar array is provided at the inlet of the channel. Various parameters affecting the dilation performance are investigated, from which the critical parameters are found to be channel aspect ratio and flow Reynolds number. An empirical relation, which can estimate the output slurry concentration as a function of aspect ratio and flow Reynolds number, is proposed. Particle accumulation patterns inside the headers are reported, and factors affecting it are discussed. Further, a technique to increase microchannel service life is discussed.