Team:IONIS Paris/Project/Game Over

Game Over

What is the Game Over?

Allowing the end of the game

The game over concerns the end of one round in the Bio-Console game.
Indeed, you can not play indefinitely with the Bio-Console, and as every funny game something can happen to the hero! Here, the end of the game is the death of the bacteria.

As you know, the goal of the game is simple: to allow BACT'Man to survive as long as possible. Stop him from getting in contact with the virtual lasers that will appear faster and faster as the game goes on. If BACT'Man were to be touched, a bright flash will appear at the microscope and will activate the liposomes opening. The toxins will eliminate our hero that will lose his fluorescence or bioluminescence ... GAME OVER
Our game over is composed of two parts : Toxin-mediated delivery by photopolymerizable liposomes , clean-up of the microfluidic channel.

Photopolymerizable liposome

Toxin-mediated delivery

In order to kill our bacteria which would imply the end of the game, we thought to use liposomes as toxin-mediated delivery. The idea is to create a bubble into the microfluidic chip containing the bacteria and the liposomes. As a result, when the bubble would touch the lasers, the liposomes would free up toxins that would kill the bacteria afterwards.

For this to be possible, we wanted to use photopolymerizable liposomes. The latter composed of photopolymerizable phospholipid (DC8,9PC) would release entrapped toxins upon visible light treatment (The photopolymerization occurs at 514 nm). Liposomes prepared from DC8,9PC alone form tube like structures that are not suitable for molecule entrapment, therefore, we thought to make a formulation containing a mixture of lipids.
In order to ensure functional liposomes, we took as reference the article written by Yavlovich et al. (2011) entitled “A Novel class of Photo-triggerable liposomes containing DPPC:DC8,9PC as Vehicles for Delivery of Doxorubcin to Cells”.

BactMan - Game Over

Because of a time issue, we did not synthesize the liposomes and therefore test the first part of our game over. According to Yavlovich’s paper and if we follow carefully its liposome formation protocol, this system has a high probability to work efficiently.

Nevertheless, visible-light induced solute leakage from the liposome depends on the spectral properties of entrapped solutes. As we did not test the liposomes with the toxins, we cannot say if the leakage will be important or not. In any case, we do not really have to worry about it since we play upon red light.

					
						Light signals
						
						Liposomes
						
						Bio-Console
						
						 Game over

References

Yavlovich A, Singh A, Blumenthal R, Puri A. A novel class of photo-triggerable liposomes containing DPPC:DC 8,9PC as vehicles for delivery of doxorubcin to cells. Biochim Biophys Acta - Biomembr. 2011;1808(1):117–26.