mikrofluidijärjestelmät

Microfluidics is the science and technology of precisely controlling and manipulating fluids at submillimeter scales. Devices typically operate with channel dimensions from tens to hundreds of micrometers, enabling handling of very small liquid volumes with high precision. Because flows at this scale are usually laminar, mixing is dominated by diffusion and deliberate channel design rather than turbulence, allowing predictable reaction times and efficient heat and mass transfer.

The field underpins lab-on-a-chip concepts, where multiple laboratory functions such as sample preparation, reactions, separation, and detection can be integrated on a single microfabricated substrate. Common materials include polydimethylsiloxane (PDMS), glass, silicon, and thermoplastics; fabrication methods include soft lithography, photolithography, etching, and increasingly 3D printing.

Approaches include continuous-flow microfluidics, where fluids are guided through networks of microchannels; droplet microfluidics, which compartmentalizes reactions in picoliter to nanoliter droplets; and digital microfluidics, based on electrowetting to move and merge droplets on a flat surface.

Applications range from point-of-care medical diagnostics and rapid chemical synthesis to single-cell analysis, genomics workflows, environmental sensing, and organ-on-a-chip models that simulate tissue and organ function for research and drug development.

Advantages include reduced reagent use, faster processing, and easy integration of multiple steps; challenges involve device standardization, manufacturability at scale, robust interfacing with macroscale equipment, and issues like fouling and sample compatibility.

As an interdisciplinary field, microfluidics combines physics, chemistry, materials science, and biology and continues to expand into industrial and clinical settings.