Viscous liquid flow rate measurement

Simply put, what issue does this document tackle?

Pushing thick fluids through tiny channels means even minor flow mistakes can disrupt mixing, alter droplet formation, or shift particle positions unpredictably. This document explains a method for monitoring and instantly adjusting slow flows of such liquids using the Galileo inline sensor. With this setup, the actual results closely align with the predicted behavior. Measurement becomes part of the process, not an afterthought.

What does the layout of the test configuration look like?

A setup built around simplicity powers fluid movement through pressure control; following that, a Galileo flow sensor takes readings directly in the line. From there, output flows into either a collection tube or reservoir – ready for weight checks or further examination down the path. Nothing more. What stands out is constant in-line tracking rather than waiting until the very end to measure, providing clear sight into shifts, blockages, or irregular pulses.

How fast does the system move fluid?

The note reports stable measurement and control over a range of roughly 0.5 to 50 µL/min with viscous test liquids. That range comfortably covers many droplet-generation, encapsulation, and microparticle workflows that operate in the single- to double-digit µL/min range.

What happens when viscosity varies in Galileo? Pre-calibrated across multiple viscosity levels, the device works with disposable cartridges snapped into place. Fluid flows solely within the cartridge interior, allowing quick swaps – either for new flow targets or to prevent mix-ups between formulas. This design eliminates the need to reconfigure plumbing whenever viscosity or operating range changes.

Yet small blockages and gradual slowdowns often escape attention.

Ahead of failure, visibility matters. The system shows fluid movement as it happens – making small shifts obvious at a glance. When something changes, like buildup or uneven flow, a built-in signal lights up without delay. Instead of missing slow problems, users spot them early. Under thick-flow conditions, this feature prevents silent breakdowns from ruining results.

What kinds of programs gain the greatest advantage?

Fine changes in flow rate matter most when handling fluids that react to stress or thickness shifts – examples include making emulsion drops, crafting nanoparticles, guiding cells or beads, pushing fluid across membranes, or blending substances under control. For such tasks, maintaining a steady flow of 1 to 2 microliters per minute often determines whether results are consistent or completely off.

What role do cartridges play in maintaining cleanliness and preventing contamination?

Because the liquid route remains inside the cartridge, assign one unit to sterile or protein-rich samples, while using a separate unit for solvents or fluids rich in glycerol. Switching between them requires only moments; meanwhile, leftover residue from thick liquids becomes far less likely. In environments under strict oversight, tracking across batches becomes easier – each cartridge serves as a distinct, swappable part.

Is it possible to complete the circuit for automatic regulation?

Yes. The workflow favors pressure-driven actuation precisely because it responds quickly and smoothly to measured flow. In most labs, you’ll run Galileo’s live signal into your control software, adjust upstream pressure to hold a setpoint (e.g., 8.0 µL/min), and log both commanded pressure and measured flow for reproducibility. If you later switch to a higher-viscosity formulation, you keep the same logic – only the pressure, flow mapping moves.

What happens when comparing it to syringe-pump measurements of thick fluids?

It turns out syringe pumps display what they aim for, not what actually flows through the microfluidic channel. Viscosity changes, flexible tubing, temperature shifts, and downstream resistance often mean reality falls short of the set value. Measurement right inside the fluid path – like the one pictured – shows exactly what moves where, including any pulses hiding beneath steady averages. This kind of monitoring enables immediate adjustments, which explains its role here despite highly calibrated driving systems already in place.

What calibration and performance details matter for reviewers?

Two things usually satisfy peer reviewers and QA teams: a viscosity-aware calibration (so the scale doesn’t silently shift when you move from aqueous to viscous media) and a documented, cartridge-specific flow range. The application note explicitly focuses on viscous liquids and low-flow operation (down to about 0.5 µL/min), with cartridge swaps to adapt the range and prevent cross-contamination. It’s a pragmatic approach to traceability without over-engineering the rig.

Where does the Microfluidics Innovation Center fit in if we plan a Horizon Europe project or need a prototype?

Home to practical solutions when microfluidics meet real-world demands, the Microfluidic Innovation Center steps in during early Horizon Europe planning or when a functional prototype takes shape. Instead of just supplying parts, MIC integrates full systems – sensors, actuators, chips, controls – into one coherent unit. Custom chip fabrication follows, tailored not to ideal conditions but to actual laboratory environments where precision matters. Think durability first; these are devices meant to operate day after day without fail. Often joining EU-funded collaborations as the go-to expert for automation and fluid handling, the center contributes by shaping experimental approaches, selecting measurement tools, and assembling user-ready platforms. Biologists and chemists benefit directly – they interact with robust equipment designed for consistency, not constant troubleshooting. Evidence from earlier grants shows proposals involving MIC clear hurdles at roughly twice the rate expected on paper alone.

What useful ideas rarely show up in research articles?

Some steps help maintain consistency across testing days. Warming thick samples to a steady temperature happens before calibration. Rigid, short tubes connect above the sensor to reduce flex. Alerts about blockages or fluctuations get recorded with exact times. Switching fluid types means swapping cartridges instead of adjusting zero on the old one. Small actions like these link later results back to early baselines.