A simple microfluidic tool to design anisotropic microgels

Many different techniques have been reported for the generation of monodisperse microgels, however, control over shape and material composition without overcomplicating the set-up remains difficult. While some batch processing techniques can produce high resolution complex shapes, they offer less flexibility. Microfluidic techniques, on the contrary, are ideal tools for generating monodisperse droplets as precursors for soft microbeads. Unfortunately, microfluidic tools have not yet been utilized to their full potential, commonly generating spherical droplets consisting of one material only. Here, we combine aqueous-phase-separation with microfluidics to generate double emulsions. Depending on the materials used, microgels having either asymmetry in shape or asymmetry in material composition are obtained. We show the versatility of this microfluidic design to generate biocompatible microparticles of two or more immiscible, aqueous solutions of which at least one is polymerizable and give a detailed description on how to make these microparticles including some crucial handling steps.

Automated summary

The article introduces a method that combines aqueous-phase separation with microfluidics to generate asymmetric microgels, expanding the application of microfluidic technology. This method can prepare biocompatible microparticles with high flexibility and diversity.