IGEM:IMPERIAL/2009/Encapsulation/Phase2/Outer Capsule

2nd Shell - Crystal Deposition

Following autoencapsulation with colanic acid, it will be necessary to encapsulate the cells in a crystal shell that will faciliate transport and storage.

This crystal shell must achieve two things:

1) Must be non-toxic and edible.

2) Must be deposited rapidly.

3) Must dissolve in the stomach.

Many of you will be familiar with heat pads - but did you know that they contain sodium acetate? Sodium acetate is edible, cheap and supersaturated solutions crystalise instantly!

What is more, the crystalisation process is highly exothermic so the heat produced will be able to trigger the temperature sensitive kill switch (Module 3)!

A supersaturated solution of sodium acetate requires a nucleation site to initiate crystalisation. The highly negativly charged colanic acid capsule of the bacterium will be highly suitable for this task.