Team:NCTU Formosa/Project/Introduction

Motive

Fresh food displayed in preservation storage in supermarkets often lack definite assurance of its freshness, so we think it’s necessary to examine whether the foods are undergoing bacterial contamination or not. Although the importance of controlling food quality is well known, it’s hard to design an economical mechanism which could calculate the population of the bacteria contaminating the food. What’s more, could determine an actual expiration date depending on the circumstances of the food at the moment rather than presuming one.

To overcome this problem, we want to design a genetic circuit in E. coli, and to serve it as both counter and timer. The constructed E.coli works as a referee and uses fluorescent proteins with different colors to reflect the state of food. The green fluorescence means that the referee system is turned on and the environment is free of bacterial contamination, whereas yellow means the system is beginning to lose its freshness, and red warns us that there is bacterial contamination or that the food in storage has expired. When the red light appears, the food in storage become unedible!

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Application

The device we designed contains the functions of Timer and Bacterial Detection; It can mainly be applied in:

1. Food preservation
2. Contact lenses
3. Trauma dressings

The roughly applications are as follow animation:

1. Food Preservation
We break up the inner package and release the lactose, which starts the circuit. The bacteria will soon translate the GFP protein and then appear green color. Few hours later, RFP protein will be produced and warn us of the bacterial contamination or the expiration of the foods. At the same time, the bacteria will suicide because of the ccdB protein. If the system is contaminated during the working, the same output will appear and will lead to the same result as above.

2. Contact Lenses
Just like the food preservation, we can put the package with lactose into the contact lenses. The timer function can remind us that we have worn too long and must take a rest. If the bacteria invaded, the circuit will secrete the RFP protein. The whole contact lenses will become red and warn us of the bacterial contamination.

3. Wound dressings
As the application above, our project can also contribute on the wound dressing. It can remind us to renew the ointment, or warn us of the bacterial contamination.

Extended applications: More functions to our bacteria .

1. In addition to the food preservation, we can also make the circuit secrete some material so as to protect from the invaded bacteria.
2. The circuit can use to defend our eyes against invaded bacteria. It can also eliminate the excessive protein secreted from our eyes.
3. It can be applied to the wound dressing that to secrete antibiotics or other substances to fight against the invaded bacteria. It can even aid healing.

In short, we want to create a much more convenient or much easier way to reflect the bacterial contamination or to fight against the invaded bacteria. Referee fulfills the goal in an obvious and succinct way. We wish that the project in application can promote the living standard of human beings.