Microfluidic generation of alginate hydrogel beads for cell encapsulation and 3D cell culture

• Main Author: Lu, Kaidi
• Other Authors: Hou Han Wei
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/168415
• Institution: Nanyang Technological University

Microfluidic has emerged as a promising approach for biological and biomedical research, particularly in the areas of diagnostics, cell culture and tissue engineering. The precise control of fluid flow and the ability to manipulate the cellular microenvironment in microfluidic systems make them an ideal tool for studying cellular behaviour, cell-cell interactions, and tissue formation. The objective of this project is to fabricate a droplet microfluidic device to alginate droplets and evaluate their effectiveness in maintaining cellular viability. The device fabrication method involved photolithography and soft lithography and droplets of uniform sizes (~100 µm) were produced by on-chip crosslinking of alginate and Calcium-EDTA. We first optimised the conditions for stable alginate hydrogel droplet production by characterization of its size and shape using different alginate and surfactant solutions and flow rate, and ensuring minimizing droplet coalescence collected off-chip. A droplet storage chamber was designed to trap and release droplets based on density differences. Finally, cells were encapsulated in alginate droplets using the fabricated device for cell staining assay to assess cell viability. The results showed that the developed microfluidic device was capable of generating uniform and consistent alginate droplets, with high levels of cellular viability. Taken together, the precision and reproducibility offered by microfluidics greatly improve the efficiency and accuracy of cell-based assays, making it an attractive approach for drug discovery and clinical diagnostics.