Droplet Detection and Sorting System in Microfluidics: A Review

Abstract

Since being invented, droplet microfluidic technologies have been proven to be perfect tools for high-throughput chemical and biological functional screening applications, and they have been heavily studied and improved through the past two decades. Each droplet can be used as one single bioreactor to compartmentalize a big material or biological population, so millions of droplets can be individually screened based on demand, while the sorting function could extract the droplets of interest to a separate pool from the main droplet library. In this paper, we reviewed droplet detection and active sorting methods that are currently still being widely used for high-through screening applications in microfluidic systems, including the latest updates regarding each technology. We analyze and summarize the merits and drawbacks of each presented technology and conclude, with our perspectives, on future direction of development.

On-Chip Photonic Detection Techniques for Non-Invasive In Situ Characterizations at the Microfluidic Scale

“…Epifluorescence (also simply named fluorescence) microscopy is highly sensitive and the most classical and widely used technique for detection in microfluidics [ 34 , 52 , 53 , 54 , 55 ]. In a classical configuration setup, an excitation light is directed onto the sample through a dichroic mirror that reflects the shorter wavelength excitation light towards the sample, while allowing the longer wavelength emitted fluorescence to pass through.…”

Verification of the Inverse Scale Effect Hypothesis on Viscosity and Diffusion by Azo-Amino Acid Schiff Base Copper Complexes

“…A geometric theoretical model dealing with droplet size dependence was proposed [18]. Additionally, droplet detection and sorting are externally observable physical parameters based on impedance, fluorescence, and scattering/absorbance [19]. The droplet (formation) mechanism and also the internal reaction environment are complex and controlled by numerous conditional parameters such as surface tension, viscosity of two immiscible liquids, surface wetting properties, inertia, elasticity, and surfactant addition.…”

Recent Progress of Droplet Microfluidic Emulsification Based Synthesis of Functional Microparticles

“…[26,27] Therefore, microfluidic technology has shown incomparable advantages over other technologies in the continuous and controllable construction of monodisperse functional microparticles with various structures and functions. Till present, in the aspect of droplet microfluidics, the development of biochemical analysis [28] and detection technology [29,30] have been summarized vis reviewing the basic principles [31] and fundamental applications. [32] Differently, this review focuses on recent developments in the preparation of novel functional microparticles by droplet microfluidics and their emerging applications, as shown in Figure 1c.…”

“…Till present, in the aspect of droplet microfluidics, the development of biochemical analysis [ 28 ] and detection technology [ 29 , 30 ] have been summarized vis reviewing the basic principles [ 31 ] and fundamental applications. [ 32 ] Differently, this review focuses on recent developments in the preparation of novel functional microparticles by droplet microfluidics and their emerging applications, as shown in Figure 1c .…”