UC Irvine

Microfluidic devices scale down to the size of a single cell, allowing studies in individual cells. The thesis focuses on developing a new method to create individual compartments with gelatin methacryloyl hydrogel for cell trapping and cell pairing microfluidic devices efficiently. The individual gelatin methacryloyl compartments at the cell traps and cell pairing sites allow long term cell culturing for further studies and observation of the target cell or cell pairs.

The compartments were created by photopatterning gelatin methacryloyl and photoinitiator- Irgacure 2959 mixture. The mixture crosslinked when exposed to the ultraviolet light. The light source for this project was the inverted microscope- Olympus IX51. Instead of creating a compartment one site at a time according to previous work, the new method allowed the process to be done in one or two exposures within 30 seconds and created 50 to 100 compartments. After experimenting on the testing microfluidic device, the procedure was finalized. The method could not create the same patterns on the devices with microstructures. A possible cause of the unsuccessful photopatterning is the refraction of light through polydimethylsiloxane microstructures. Future improvements of the method are expected in two aspects. One is the refraction of light and the other is the material of microstructures. A possible way is to lower the refractive index either by changing the property of polydimethylsiloxane or change to other materials. Another possible method is to use gelatin methacryloyl as the material of microstructures.