Day 21

Utilisation of On/off Valves in Microfluidics 

Microfluidic valves are a great asset to direct and micromanipulate flows of fluids. For instance, with a microfluidic manifold and inline connected valves one can mix various fluids with different specimen concentrations, thus, enabling chemotaxis experiments and dose-dependence studies.  

Valves, however, typically have mechanical limits, e.g., valves often have a preferred flow direction and a maximum applicable pressure range when the valve is closed. These mechanical limitations often prohibit their use in volume-driven systems since a proved volume flow, e.g., by a syringe pump, could easily damage a valve due to the high internal system pressure. 

However, in pressure-driven system, valves are a perfect choice for fluid controls when precise and quick switching of fluids is required. In the perfusion head PH-8 we also use high-precision and fast-switching on/off valves, which withstand forward pressure up to 2 bars and backward pressures of up to 500mbar rendering them a perfect solution for any pressure-driven system, such as our P2CS in combination with our Fluid Switch FS with perfusion heads PH-X.