Day 14

November 8, 2011

The goal for today was to create a non-linear gradient. Kellin had never tried making this before, so it was going to be an interesting experience. It was the same process as what I did the other days just with different volumes. We did two different trials. In the first one, we added 5 microliters of the mixture of gelatin and protein onto the inlet of the channel every minute. In the second trial, we added 5 microliters onto the inlet adding 2 minutes on the previous time. For instance, we first started with waiting for 2 minutes. After 2 minutes, we then added 5 more microliters and then waited for 4 minutes. Meanwhile, I asked about the purpose of the channel and gradient and what it was for. Kellin explained that once the gradient was  made, they will electrospin fibers onto it in a way that the fibers are aligned parallel inside the gradient. Then they will wrap the gradient around a wire. Then a few days later they will peel it off from the wire and the gradient will be cylindrical. If it works, they'll inject the gradient into a rat to test it. They will cut open the leg of a rat and cut the nerve. Then they will place the gradient there and stitch up the leg. For a few days, the rat won't be able to move that leg, but the goal is that the nerve will regrow through the gradient and reattach itself. By the time he finished explaining, the gradients were both done. We walked over to a different hospital about 5 or 10 minutes away to use this machine called a typhoon. The typhoon measures the concentration and structure of gradients. We saw that one of the gradients just didn't work at all, and the other gradient was closer to linear than nonlinear.   Even though we ended up failing pretty badly, it was a good experience for us to learn from our mistakes.