Date of Completion


Document Type

Honors College Thesis


College of Engineering and Mathematical Sciences

Thesis Type

Honors College

First Advisor

Dr. Rachael A. Oldinski

Second Advisor

Dr. Darren L. Hitt

Third Advisor

Dr. Frederic Sansoz


microfluidics, flow-focusing, silanization, silane, PDMS, poly(dimethylsiloxane), droplet generation, confocal, dripping, jetting, scaffold, arthritis


While the lifespan of humans has increased, the durability of cartilage has not, leading to increasing rates of arthritis in aging humans. As both natural and surgical methods for repairing osteochondral defects tend to fall short, UVM’s Engineered Biomaterials Research Laboratory (EBRL) is working towards a solution where biomimetic, polymeric, and porous engineered tissue scaffolds are seeded with drugs and human mesenchymal stem cells (hMSCs). The seeded scaffold is then implanted or injected into the patient’s osteochondral defect, where the hMSCs differentiate and grow a new cartilaginous extracellular matrix to heal the defect as the artificial scaffold breaks down.

Microspheres in three distinct size ranges are required to create pores and embed drugs and cells in the scaffold. In order to produce these microspheres, we turn to the field of microfluidics, which examines fluid interactions at micro-scale geometries and flow rates. A microfluidic flow-focusing device (MFFD) leverages the low Reynolds numbers and pronounced effects of surface tension in such flows to create highly monodisperse droplets of one fluid in a second.

This project investigates the design and fabrication of MFFDs for the production of homogeneous microspheres. A MFFD must be consistently reproducible, readily characterized, and easy to test and use. MFFDs show great potential to successfully play a role in the EBRL’s investigation of engineered tissue scaffolds.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.