Streamline based design guideline for deterministic microfluidic hydrodynamic single cell traps

Abstract

A prerequisite for single cell study is the capture and isolation of individual cells. In microfluidic devices, cell capture is often achieved by means of trapping. While many microfluidic trapping techniques exist, hydrodynamic methods are particularly attractive due to their simplicity and scalability. However, current design guidelines for single cell hydrodynamic traps predominantly rely on flow resistance manipulation or qualitative streamline analysis without considering the target particle size. This lack of quantitative design criteria from first principles often leads to non-optimal probabilistic trapping. In this work, we describe an analytical design guideline for deterministic single cell hydrodynamic trapping through the optimization of streamline distributions under laminar flow with cell size as a key parameter. Using this guideline, we demonstrate an example design which can achieve 100% capture efficiency for a given particle size. Finite element modelling was used to determine the design parameters necessary for optimal trapping. The simulation results were subsequently confirmed with on-chip microbead and white blood cell trapping experiments. V C 2015 AIP Publishing LLC.

Separation of sperm and epithelial cells based on the hydrodynamic effect for forensic analysis

“…20,23 Thus, researchers have used computational fluid dynamics analysis in microstructure design more frequently to obtain a more accurate and rapid solution. 24,25 In this work, Comsol was used to obtain the optimal hydraulic resistance distribution in the microchannel. We iteratively optimized the channel design by altering variable parameters of the geometry.…”

Deterministic trapping, encapsulation and retrieval of single-cells

“…42 As the incoming cells are distributed randomly across the cross-section of the channel, one can increase the probability of cell capture by increasing the ratio of the flow through the trapping pathway over the flow through the bypassing channel (Q trap /Q bypass ). 42, 43 It has been shown that a particle is preferentially directed towards a vacant trapping pathway if and only if Q trap >Q bypass .…”

“…42 As the incoming cells are distributed randomly across the cross-section of the channel, one can increase the probability of cell capture by increasing the ratio of the flow through the trapping pathway over the flow through the bypassing channel (Q trap /Q bypass ). 42, 43 It has been shown that a particle is preferentially directed towards a vacant trapping pathway if and only if Q trap >Q bypass . 39, 43–45 However, increasing the hydrodynamic resistance of the bypass channel by using a lengthy channel causes multiple problems: (1) cell clogging due to a limited shear rate through the bypassing pathway 46 ; (2) high pressure differential exerted on the captured cells 47 ; and (3) multiple particles per trap.…”

Microfluidic Sample Preparation for Single Cell Analysis

“…166 The authors demonstrated 100% cell trapping with HeLa cells. The device design provides deterministic single cell trapping akin to that demonstrated by Guan et al 162 However, this format does not require long bypass channels to achieve optimum flow resistances. The isolation methods utilizing hydrodynamics and physical obstructions as discussed above are beneficial because they are passive and can be adopted for various cell sizes and shapes.…”