A Novel Approach for Tuning of Fluidic Resistance in Deterministic Lateral Displacement Array for Enhanced Separation of Circulating Tumor Cells

Deterministic lateral displacement (DLD) is evolving as an effective passive technique for seclusion of circulating tumor cells (CTCs) functioning based on nonuniform splitting of laminar flow moving through an array of micropillars. In this research work, an unconventional approach has been presented to alter the fluidic resistance between micropillars in asymmetric DLD array for better separation of CTCs in a blood sample. This paper is aimed at introducing an innovative approach using electrical network analogy for tuning of fluidic resistance resulting in enhanced seclusion of CTCs from WBCs implementing the concept of asymmetric DLD array. The paper also describes the computational analysis of a microfluidic device using tuned asymmetric DLD array technique. A cognitive clinical decision support system for identification of CTCs based on the model is also illustrated. In this paper, computational fluid dynamics approach has been used through simulation of the microfluidic device in COMSOL Multiphysics 5.4 software to effectively regulate the trajectory of differently sized CTCs and WBCs. A novel mathematical fluidic resistance tuning approach has been introduced to design the DLD array for effective segregation of different varieties of CTCs realized by computational visualization of trajectory working on Navier-Stokes equation. The proposed design of microfluidic device isolates three distinct CTCs, i.e., lung cancer CTCs, prostate cancer CTCs, and breast cancer CTCs of diameters 22.5 mu m, 10.64 mu m, and 13.1 mu m, respectively, from tiny WBCs of diameter 12 mu m with separation efficiencies above 90% at a high sample flow rate of 20 x 10(-6) kg/s, thereby offering higher throughput. The tuning model of fluidic resistances between micropillars has been shown to offer minimal resistive effect to the required CTC trajectory while maintaining uniform pressure distribution around micropillars.