Microfluidic Recirculation System - Discover our new highly compact and automated recirculation module

In microfluidics, controlled shear stress is often required for a large variety of biological applications using cells. To address this demand, Fluigent developed a new technology that allows for automation and accuracy during your recirculation protocols: a microfluidic recirculation system. It is currently integrated into the Omi, one of our new products, but can also be combined with custom projects. 

Fluigent’s years of research experience are blended into this technology, with our pressure-based flow control allowing for highly stable and responsive flow rates. It is versatile and sterile, allowing for multiple types of microfluidic protocols, and easily transportable - with all of the components merged into one unit.  

Technology description  

Pressure-based flow control for stable pulseless recirculation

Pressure controllers are known to offer low response times with more accurate and stable flow profiles than peristaltic pumps. Indeed, the latter induces pulsed flow rates – which you can see on the graph below – and often lacks precision and accuracy. This major difference makes pressure-based flow controllers more suited for biological applications manipulating cells because they induce shear stresses more comparable to the ones observed in vivo. 

Fluigent’s recirculation system allows for automatic refills to perform perfusion continuously

Microfluidic recirculation setups often require the use of many different components such as valves, pressure controllers, flow rate sensors, tubing, reservoirs, and pressure sources. Our new system combines all of them in one compact device with a user-friendly touchscreen. Users only need to provide a microfluidic chip.  

Moreover, our microfluidic recirculation system can monitor the volume of reagent present in the reservoirs with the use of optical level sensors developed by Fluigent. Our algorithm then activates or inactivates the right valves to ensure a fast and responsive refill from the outlet reservoir to the inlet one when needed, performing continuous perfusion. 

Unpluggable cartridges

The cartridges used are disposable, allowing for sterility and reproducibility, useful for a large variety of applications requiring a contamination-free environment.  

Automation and software integration

Fluigent’s software can manage several recirculation modules at the same time. The protocols can be monitored directly from our interface to perform different microfluidic steps such as perfusion, injection, sampling, or recirculation for which the user can set all parameters. The data, collected and stored through a cloud service, can be visualized and analyzed via graphs in real-time and afterward. 

A remote control is offered using Wi-Fi, and a custom Android app can be developed by our team for easy access to control. All of these functionalities are also displayed in a web interface, consultable at any time with a browser. 

Performance of Fluigent microfluidic recirculation system

With a set perfusion flow rate of 500 μL/min, the recirculation module can maintain a constant flow rate with regular refill steps for days without any offset or issue related to the emptying of the reservoirs. In the graph above, one can see the evolution of the flow rate during 7-hour periods of a 4-day experiment. 

Microfluidic applications related to microfluidic recirculation systems

The system is particularly useful for dynamic cell culture, allowing cells to maintain under medium continuous perfusion for more than 15 consecutive days. Additionally, due to its high transportability, the platform allows users to optically analyze cells while maintaining them under given physiological conditions. 

This platform is also well-suited for drug screening applications, allowing users to inject several solutions and analyze cell reactions.  

Finally, organ-on-a-chip protocols can benefit from this technology. Indeed, the combination of a microfluidic chip with our recirculation module allows precise modeling of liquid/liquid or liquid/air interfaces to mimic in vitro the in vivo functioning of several organs. 

More information about our new technology is available here