An Open Microfluidic Chip for Continuous Sampling of Solute from a Turbulent Particle Suspension

High solids content complicates in situ analysis of chemical processing, biological suspensions, and environmental streams. In most cases, analytical methods require at least one pre-treatment step of a small volume of sample before a particle-free fluid can be analyzed. We have developed a continuous in situ sampler that can sip particle-free solution from a turbulent high solids content stream (a slurry). An open microfluidic chip with an extended slit opening shields the internal laminar flow from the turbulence outside. Unlike other open chips, our chip does not require close proximity to a solid surface and operates in turbulent environments for hours without maintenance. Two applications are demonstrated: monitoring Fe-III in a stirred slurry of mixed ore particles at high solids loading (4 %wt) and paracetamol tablet dissolution profiles for two different formulations.

Automated summary

The study developed a continuous in situ sampler that can extract particle-free solution from a turbulent high solids content stream without needing to be close to a solid surface. Two applications were demonstrated: monitoring Fe-III in a stirred slurry of mixed ore particles and dissolution profiles of paracetamol tablets with different formulations.