Cells which contain logic gates and take part in
cell-to-cell signaling demand a very specific environment in order for
the system to work properly. Since the logic gates are intended to be
used as information storage as to whether a contaminant has passed and
are designed so monitoring does not need to be continuous, the cells
must be able to survive and remain active for several days inside the
device. Furthermore, the cell-to-cell singaling requires that the cells
are suspended in such a manner that AHL diffusion is efficient and that
they can induce one-another in an efficient manner. In order to support
both of these, we designed a special hydrogel scaffold made out of
crosslinked polyvinyl alcohol. PVA hydrogels are commonly used in
biomaterials based on its hyrdophilic nature which can attract moisture
and nutrients to keep the cells alive, its pore size which allows for
the diffusion of proteins and sugars while holding the cells in a
relatively fixed position, and its biodegradability, which is
attractive in the context of making an environmentally-conscious
product.
In early September, PVA scaffolds were made which contained cells with
the pBad inducible promoter in front of the RFP gene, and experimental
results support the hypothesis that the engineered E. coli were able to
live inside and respond to arabinose when soaked in the solution.
Designing for Environmental Functionality
Creating a User-Friendly Device
Future Directions for Development
Further experimentation is required to determine
the
feasibility of AHL diffusion in cell-to-cell signaling, extensive cell
growth studies to see if the system, and