Generation of hydrogel microparticles using a portable droplet microfluidics system

• Main Author: Cheng, Cindy Xiuyi
• Other Authors: Hou Han Wei
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2025
• Subjects: Engineering
• Online Access: https://hdl.handle.net/10356/181915
• Institution: Nanyang Technological University

Droplet microfluidics has gained significant attention as a valuable tool in recent years due to its ability to precisely compartmentalize tiny fluid volume (~pL) and generate monodisperse droplet sizes. Besides high throughout drug screening, another key application in tissue engineering involves the 3D encapsulation of cells within hydrogel particles to support cell proliferation. However, most existing setups rely on bulky and expensive pumps which limit portability and translation to clinical use. Here, we aim to develop a compact and portable droplet microfluidic pneumatic system capable of encapsulating cells within hydrogel (GelMA) microparticles (~100 to 200 µm). Microfluidic devices were fabricated using photolithography (SU8), and on-chip and offchip UV crosslinking methods were compared to enhance droplet uniformity and stability. A compact portable pump system comprising of 2 pneumatic pumps, pressure sensors, an inline curing holder, collection tube holder, microfluidic device holder, and curing device storage was designed and fabricated using 3D printing. As a proof of concept, liver cells (HepG2) were encapsulated within GelMA droplets and on-chip crosslinking produced more uniform droplets and reduced coalescence as compared to off-chip methods. Encapsulated cells also exhibited high viability, indicating the system’s biocompatibility and potential in 3D cell culture. Overall, this portable microfluidic system provides an efficient and scalable solution for on-site droplet production to advance research in drug delivery and tissue engineering.