Microfluidics deals with the precise control and manipulation of small volumes of fluids and is a discipline of fluid mechanics. Typically, such volumes are in the sub-milliliter range and are constrained to micrometer-scale channels. Liquids exhibit peculiar behaviour at this scale. Microfluidic devices can thus benefit from such effects. The flow of liquids in microfluidics is typically laminar.
Microfluidic devices are used for pumping, sampling, mixing, analysing, and dosing liquids. Closed flow paths in microfluidic devices facilitate the integration of functional elements (e.g., heaters, mixers, pumps, UV detector, valves, etc.) and minimize problems related to leaks and evaporation at the same time. The analysis of liquid samples often requires a series of steps (e.g., filtration, dissolution of reagents, heating, washing, reading of signals, etc.). Metallic electrodes are sometimes patterned in channels of the device.
Microfluidics has opened the door for applications in many areas of health care and life sciences, such as point-of-care diagnostics (POCDs), environmental analysis, and drug discovery. POCDs strongly benefit from microfluidic technologies due to the miniaturization of tests, which enhances portability and the integration of various functions into one diagnostic device. For instance, many lateral flow tests rely on microfluidic functions and microfabrication to increase their precision and multiplexing capabilities.