Its the final week of the RET experience within the lab setting. Our research has wrapped up and we are computing the data with the remaining time. My mentor intends to continue his research topic after I have left but not before a short hiatus. It feels like we just started a week ago and here we are all getting ready to board plans and head back to Houston for the Symposium.

This last week was very data heavy.  We decided to run four samples instead of two. Not only that but we also started reducing the amount of current we were applying to our cultures. We noticed that when we cut it in half after a minute all the biofilm was removed. So we cut that in half and we noticed that after about five minutes all the biofilm was removed. This is important because the less electricity that’s required the cheaper it is to use this method of cleaning membranes. My mentor is being Assigned to a different research project and as a result I am taking over this current project for my remaining time. This is awesome and scary at the same time since we are now sharing our measurement device with another group. Our cultures are required to stay in one place and not be moved at all and that’s going to be very hard when we have another group that wants to use the device that we store them on.

I don’t really have much to update on this week.

This week we tested four cells at the same time. We reduced the mA from our previous tests. The graphs on the left are with a 25mA current applied and after the first 2 minutes all biofouling had been removed which was really great. The 2 on the left we dropped the mA to 12.5 and saw that it only marginally effected  the amount of time required to remove all of the biofouling. We are planning on creating additional cells and finding out how low we can drop the mA before biofouling is no longer removed. for each graph there are roughly 12 sets of data with 17 data points per that are averaged together and then normalized.

This week we finished setting up our first plates to test since I the RET program has started. We tried a different type of tape to hold down our membrane in the hopes that it would be non-conductive allowed all the conduction to take place in the membrane. Unfortunately, the tape showed signs of being conductive and also lost adhesion during the testing process.

We decided to wait an extra day before starting our experiment and as a result a thin layer of membrane like mucus formed at the very top of the dish. We had to remove this layer as best as we good with our mini net. The layer broke apart into smaller pieces and made recording accurate data a real pain.

One of our two dishes did provide good data as show on the computer screen below. The 1st image shows the setup of the experiment. The OCT and our two dishes connected to a anode (red) and Cathode (black).

The image below is of our membrane the solid white layer at the bottom and the biofilm the spotted layer above it. This was our recording before we began applying a current. It shows a clear build up of biofilm that we are trying to remove. It is a pretty beautiful image when you see it up close.

Week1

First day on site my mentor ran me through how to use a Optical Coherence Topography device to measure biofilm thickness on our membrane. The topography is actually a device you would see in a optometrists office. Its designed to take cross section pictures of retinas.

From there we created a new batch of bacteria, plated it and incubated it until it was ready to be refrigerated.

On the device below a Hach Odyssey Spectrophotometer we checked to make sure our bacteria had replicated into large qualities before plating them.

I was introduced to a Epifluorescence Microscope.  Leica DM6 B

My mentor is out of town for the rest of the week and has given me data to record using the imaging software Thorimage and ImageJ. I had/have to render a 3d and 2d image from the OCT and measure the volume of the biofilm on roughly 20-30 different samples. Below is a 2d and 3d image in Thorimage.

Video (2)

And then if this post put you to sleep your not the only one?

Lets go!