Ultra low-cost fabrication of homogeneous alginate hydrogel microspheres in symmetry designed microfluidic device

TL;DR

This paper introduces a simple, cost-effective microfluidic method for producing uniform alginate hydrogel microspheres without surfactants or demulsifiers, enhancing ease of fabrication and separation.

Contribution

A novel two-stage microfluidic device design enables low-cost, homogeneous alginate hydrogel microsphere production with simplified separation process.

Findings

Monodisperse alginate hydrogel microspheres achieved

No surfactants needed for droplet formation

Easy separation from oil phase via oscillation

Abstract

In this study, we present a two-stage method for fabricating monodisperse alginate hydrogel microspheres using a symmetrically designed flow-focusing microfluidic device. One of the flow-focusing junctions generates alginate hydrogel droplets without the addition of surfactants, while the other junction introduces corn oil with acetic acid, which facilitates the solidification of the homogeneous alginate hydrogel droplets and prevents coalescence. These hydrogel microspheres can be easily separated from the oil phase using an oscillation state, eliminating the need for a demulsifier. This microfluidic system for hydrogel microsphere formation is notable for its simplicity, ease of fabrication, and user-friendliness.