The study of mixing of reagents within a droplet in various designs of microfluidic chip

3rd International School and Conference on Optoelectronics, Photonics, Engineering and Nanostructures (Saint Petersburg OPEN 2016)

Filatov, N.A.^1 ; Belousov, K.I.^2,3 ; Bukatin, A.S.^1,3 ; Kukhtevich, I.V.^3 ; Evstrapov, A.A.^1,2,4

Nanobiotech Lab, St. Petersburg Academic University, St. Petersburg

194021, Russia^1

Department of Nanotechnologies and Materials Science, ITMO University, St. Petersburg

197101, Russia^2

Department of Biophysics, Siberian Federal University, Krasnoyarsk

660041, Russia^3

Laboratory of Information and Measurement Biosensor and Chemosensor Microsystems, Institute for Analytical Instrumentation RAS, Saint Petersburg

198095, Russia^4

关键词: Asymmetric design;    Capillary numbers;    Continuous phase;    Droplet formation;    Droplet generators;    High viscosities;    Microfluidic chip;    Microfluidic droplets;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/741/1/012052/pdf
DOI  :  10.1088/1742-6596/741/1/012052

来源: IOP

【 摘 要 】

The aim of this work was to determine a design of a microfluidic droplet generator which provides the best mixing of two components within a droplet during its formation. Simulation of droplets' formation in various designs of microfluidic generators was performed. Dependences of a mixing index from a capillary number and a viscosity of continuous phase were obtained for each design. The mixing index was determined directly after the formation of the droplet. It was found that the small capillary numbers correspond to the lower mixing index due to increase of the droplets diameter. The high viscosity of the continuous phase provides vortex flows in the area of droplet formation which leads to an increase in the mixing index for asymmetric designs, but has no significant effect on the mixing in conventional symmetric flow focusing. So for the asymmetric droplet generator designs the mixing index increases up to 1.5 as compared with the conventional flow focusing designs.