Generation of Linear and Parabolic Concentration Gradients by Using a Christmas Tree-Shaped Microfluidic Network
SHEN Qilong, ZHOU Qiongwei, LU Zhigang, ZHANG NangangSchool of Electrical and Electronic Engineering, Wuhan Textile University, Wuhan 430200, Hubei, China
This paper describes a simple method of generating concentration gradients with linear and parabolic profiles by using a Christmas tree-shaped microfluidic network. The microfluidic gradient generator consists of two parts: a Christmas tree-shaped network for gradient generation and a broad microchannel for detection. A two-dimensional model was built to analyze the flow field and the mass transfer in the microfluidic network. The simulating results show that a series of linear and parabolic gradient profiles were generated via adjusting relative flow rate ratios of the two source solutions and , which could match well with the experimental results and . The proposed method is promising for the genera-tion of linear and parabolic concentration gradient profiles, with the potential in chemical and biological applications such as combinatorial chemistry synthesis, stem cell differentiation or cytotoxicity assays.
Key words:tree-shaped network; concentration gradient; linear profile; parabolic profile
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