Elastomeric microfluidic valve with low, constant opening threshold pressure

Abstract

This paper presents the realization of low, constant opening threshold pressures of an elastomeric valve by appropriate design and surface coating of the valve in a self-oscillating microfluidic device. The valve has a V-shaped valve seat, which separates the valve's inlet and outlet, and a membrane-pressurization bottom chamber. We utilized the V-shaped valve seat design to manipulate the mechanical deformation of the valve's membrane due to differences in applied pressure. Furthermore, we used a simple biomolecular surface coating to remove the adhesion force between the valve seat and the membrane. As such, the opening threshold pressure of our valve reduced from 13.1 to 2.4 kPa (i.e., an 81.7% reduction) at a flow rate 8 mL min À1 . More importantly, we achieved a nearly constant opening threshold pressure regardless of the change in the input flow rate (i.e., a 0.07 kPa min mL À1 pressure change rate), thereby achieving a linear oscillating frequency response of the microfluidic device. Such a valve having low, constant opening threshold pressures is envisioned to be broadly useful for sophisticated fluidic routing applications, where numerous integrated valves with low actuation pressures are necessary.

Modular fluidic resistors to enable widely tunable flow rate and fluidic switching period in a microfluidic oscillator

“…During this process, biomolecules in the solution bound on the valve surfaces and reduced the adhesive property of PDMS, thereby decreasing the opening threshold pressure of the microfluidic valves. Additional details on the microfabrication process are provided in the supporting information of .…”

“…Although dynamic controllers enable versatile regulation of chips, installing and operating the controllers are relatively costly and require expertise in electromechanics. This drawback is the motivation for the birth of instruction‐embedded microfluidic devices that mimic the operation of electronic circuits .…”

Dynamic Environmental Control in Microfluidic Single‐Cell Cultivations: From Concepts to Applications

“…The continuous regulation of the valve can be controlled with the manipulation of airflow, here pressure on chip, so that the external pressure is constant. [ 61 ]…”

Fluid-Structure Interaction Analysis on Membrane Behavior of a Microfluidic Passive Valve

“…The constant flow rate of this microvalve was 0.83 mL/min. Jaemin et al [ 21 ] performed an experimental analysis on different shaped structures in normally closed microvalve models. The study found that the microvalve can achieve a near-low constant opening threshold pressure regardless of the change in the input flow rate.…”

“…The study found that the microvalve can achieve a near-low constant opening threshold pressure regardless of the change in the input flow rate. Later, Natarajan et al [ 22 ] performed the FSI analysis on two different models (taking from [ 21 ]) in normally closed microvalve models. The characteristics of fluid flow and the behavior of membrane deformation inside the normally closed microvalve were observed.…”