3D printed alginate bead generator for high-throughput cell culture

Alginate hydrogel beads are a common platform for generating 3D cell cultures in biomedical research. Simple methods for bead generation using a manual pipettor or syringe are low-throughput and produce beads showing high variability in size and shape. To address these challenges, we designed a 3D printed bead generator that uses an airflow to cleave beads from a stream of hydrogel solution. The performance of the proposed alginate bead generator was evaluated by changing the volume flow rates of alginate (Q_Alg) and air (Q_A), the diameter of device nozzle (d) and the concentration of alginate gel solution (C). We identified that the diameter of beads (D = 0.9 -2.8 mm) can be precisely controlled by changing Q_A and d. Also the bead generation frequency (f) can be tuned by changing Q_Alg. Finally, we demonstrated that viability and biological function (pericellular matrix deposition) of chondrocytes were not adversely affected by high f using this bead generator. Because 3D printing is becoming a more accessible technique, our unique design will allow greater access to average biomedical research laboratories, STEM education and industries in cost- and time-effective manner.