The Encapuslation of Cells within A Microfluidic Device with Passive Separation through An Internal Hydrogel Filter

The encapsulation of cells within a microfluidic device through emulsion polymerization has been established. However, with the emulsion polymerization process, the resulting encapsulated cells are in an oil phase and a separation process is needed to get the encapsulated cells out of the oil. The current technique for separation is centrifugation, which is flawed because it can damage the gel membrane and it has a low recovery rate. Instead of centrifugation, a hydrogel filter will be utilized for separation. A hydrogel will be created within the microfluidic device by exposing a mixture of polyethylene glycol and a photoinitiator (DMPA) to UV light. The hydrogel will have thin slits within it, which will allow hydrophilic (encapsulated cells) substances to pass through while preventing hydrophobic (oil) substances to pass through. On the other side of the hydrogel, a phosphate buffer solution will be flowing in a counter-current flow to collect the encapsulated cells in an effluent stream. The encapsulated cells will have consistent membrane thicknesses and a higher recovery rate than that of centrifugation. These encapsulated cells can be used in cultures in biomedical, biological and biochemistry applications.