An off-the-shelf microfluidic device for the controllable fabrication of multiple-holed hollow particles and their cell culture applications

Abstract

The microfluidic droplet method has excellent promise for preparing hollow particles because it can be versatile in realizing multi-level size distribution and scalable in production. However, the application of this method is still limited due to the complexity of the device preparation process. Here, an off-the-shelf microfluidic device is developed for the fast and straightforward fabrication of highly uniform multiple-holed hollow particles. Most importantly, the structure, size, morphology, and properties of the particles can be easily adjusted by varying the fabrication conditions, including the diameter of the capillaries, the flow rate of the water and oil phases, the start polymerization time, and the composition of the emulsion droplets. Therefore, the developed device provides a powerful platform for the controllable fabrication of multiple-holed hollow particles with exceptionally diverse structures and properties. Furthermore, well-ordered hollow particle arrays were quickly fabricated for three-dimensional (3D) cell culture by a simple molding method. HepG2 3D tumor spheroids with excellent viability and uniformity were efficiently produced using the particle arrays. Thus, the multiple-holed hollow particles will offer a unique opportunity for application in various cell-based research studies.