Emergence of debubblers in microfluidics: A critical review

Abstract

Bubbles in microfluidics—even those that appear to be negligibly small—are pervasive and responsible for the failure of many biological and chemical experiments. For instance, they block current conduction, damage cell membranes, and interfere with detection results. To overcome this unavoidable and intractable problem, researchers have developed various methods for capturing and removing bubbles from microfluidics. Such methods are multifarious and their working principles are very different from each other. In this review, bubble-removing methods are divided into two broad categories: active debubblers (that require external auxiliary equipment) and passive debubblers (driven by natural processes). In each category, three main types of methods are discussed along with their advantages and disadvantages. Among the active debubblers, those assisted by lasers, acoustic generators, and negative pressure pumps are discussed. Among the passive debubblers, those driven by buoyancy, the characteristics of gas–liquid interfaces, and the hydrophilic and hydrophobic properties of materials are discussed. Finally, the challenges and prospects of the bubble-removal technologies are reviewed to refer researchers to microfluidics and inspire further investigations in this field.

Key findings

• ▸Active debubblers, such as those assisted by lasers, acoustic generators, and negative pressure pumps, are effective but require external equipment.
• ▸Passive debubblers, driven by buoyancy, gas-liquid interfaces, and material properties, are simpler but may not be as effective.
• ▸Bubble removal is crucial in microfluidics to prevent experiment failures and ensure accurate results.

Keywords

Identifiers

DOI

10.1063/5.0088551

Journal

Biomicrofluidics

Year

2022