Pulsatile Flow in Microfluidic Systems

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2020-03, Vol.16 (9), p.e1904032-n/a
• Main Authors: Dincau, Brian, Dressaire, Emilie, Sauret, Alban
• Format: Article
• Language: English
• Subjects: automation; biomimicry; Cell Culture Techniques; Flow velocity; Fluid dynamics; Fluid flow; Hydrodynamics; Microfluidics; Microfluidics - trends; Nanotechnology; oscillatory; Perturbation; pulsatile; Pulsatile Flow; Reynolds number; Steady flow
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.201904032

This review describes the current knowledge and applications of pulsatile flow in microfluidic systems. Elements of fluid dynamics at low Reynolds number are first described in the context of pulsatile flow. Then the practical applications in microfluidic processes are presented: the methods to generate a pulsatile flow, the generation of emulsion droplets through harmonic flow rate perturbation, the applications in mixing and particle separation, and the benefits of pulsatile flow for clog mitigation. The second part of the review is devoted to pulsatile flow in biological applications. Pulsatile flows can be used for mimicking physiological systems, to alter or enhance cell cultures, and for bioassay automation. Pulsatile flows offer unique advantages over a steady flow, especially in microfluidic systems, but also require some new physical insights and more rigorous investigation to fully benefit future applications. This review outlines the fundamental parameters describing pulsatile flows and summarizes contemporary applications in microfluidic systems and biological studies. These include pulsatile signal generation, droplet emulsion, accelerated mixing, particle separation, clog mitigation, mimicking in vivo pulsatile environments, enhanced cell culturing, and bioassay automation. Their added complexity expands microfluidic functionality, yet many opportunities to refine pulsatile flow theory and implementation remain.