A multi-functional bubble-based microfluidic system

Abstract

Recently, the bubble-based systems have offered a new paradigm in microfluidics. Gas bubbles are highly flexible, controllable and barely mix with liquids, and thus can be used for the creation of reconfigurable microfluidic systems. In this work, a hydrodynamically actuated bubble-based microfluidic system is introduced. This system enables the precise movement of air bubbles via axillary feeder channels to alter the geometry of the main channel and consequently the flow characteristics of the system. Mixing of neighbouring streams is demonstrated by oscillating the bubble at desired displacements and frequencies. Flow control is achieved by pushing the bubble to partially or fully close the main channel. Patterning of suspended particles is also demonstrated by creating a large bubble along the sidewalls. Rigorous analytical and numerical calculations are presented to describe the operation of the system. The examples presented in this paper highlight the versatility of the developed bubble-based actuator for a variety of applications; thus providing a vision that can be expanded for future highly reconfigurable microfluidics.

Development of a microfluidic design for an automatic lab-on-chip operation

“…The method of using the air-trapped bubbles is simple. However, air bubbles could block and influence the flow in microfluidic channels (Chang et al 2008;Khoshmanesh et al 2015). Additionally, an avoidance of air bubbles is necessarily required in some applications, e.g.…”

Microparticles manipulation and enhancement of their separation in pinched flow fractionation by insulator‐based dielectrophoresis

“…Passive sorting techniques make use of interaction between microchannel structure and the flow field with particles. Passive separation is preferred in applications where input energy is important . Pinched flow fractionation (PFF) is a passive‐based size separation technique for nanometer‐ to micrometer‐sized particles that uses a pinch region in microchannels for flow fractionation of fluid .…”

Particle manipulation via opto-thermally generated bubbles in open chip environment

“…Bubbles at micro and nano meter scale can exist stably on the hydrophobic surfaces in water, despite the high internal gas pressure may cause their dissolution predicted by the Laplace equation [1]. The different properties make bubbles useful in various microfluidics techniques, such as microfluidic computer [3], pumps [4,5], mixers [6,7], valves [8,9], and multi-functional microfluidic systems [10,11].…”