Predictable Duty Cycle Modulation through Coupled Pairing of Syringes with Microfluidic Oscillators

Micromachines

Sasha Cai Lesher-Perez¹  Priyan Weerappuli¹  Sung-Jin Kim¹  Chao Zhang¹  Shuichi Takayama¹ 

[1] Department of Biomedical Engineering, Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA; E-Mails:

关键词: microfluidics;    microfluidic oscillator;    duty cycle;   

DOI  :  10.3390/mi5041254

来源: mdpi

【 摘 要 】

The ability to elicit distinct duty cycles from the same self-regulating microfluidic oscillator device would greatly enhance the versatility of this micro-machine as a tool, capable of recapitulating in vitro the diverse oscillatory processes that occur within natural systems. We report a novel approach to realize this using the coordinated modulation of input volumetric flow rate ratio and fluidic capacitance ratio. The demonstration uses a straightforward experimental system where fluid inflow to the oscillator is provided by two syringes (of symmetric or asymmetric cross-sectional area) mounted upon a single syringe pump applying pressure across both syringes at a constant linear velocity. This produces distinct volumetric outflow rates from each syringe that are proportional to the ratio between their cross-sectional areas. The difference in syringe cross-sectional area also leads to differences in fluidic capacitance; this underappreciated capacitive difference allows us to present a simplified expression to determine the microfluidic oscillators duty cycle as a function of cross-sectional area. Examination of multiple total volumetric inflows under asymmetric inflow rates yielded predictable and robust duty cycles ranging from 50% to 90%. A method for estimating the outflow duration for each inflow under applied flow rate ratios is provided to better facilitate the utilization of this system in experimental protocols requiring specific stimulation and rest intervals.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.