Dominique Escandon - NJIT Lab - Week 4

This last week has been very exciting! Qin and I come in every day at around 12, where we either continue recording our fuel cell's voltage and current density, or, if it has already dropped to below 20% of it's original current density, we set up a new fuel cell. We had many challenges in the beginning of the week since the enzymes, which are compressed onto a sheet of carbon nanotube then sandwiched between two sheets of platinum and held by tweezers over our buffer and glucose solution (to simulate glucose levels in the body), tend to fall from the setup, especially GOx since it doesn't compress too well. We are experiencing with dipping the carbon nanotube in Nafion to create a membrane that will hold onto the enzyme better, and soaking our carbon nanotube in pure GOx solution overnight so it is properly absorbed. This should create larger pores on the CNT surface, which will make it more reactive and adhesive towards GOx.

Something interesting that has happened is that our solution changed colors overnight. Normally, the buffer and glucose solution is a light pink, but recently it turned a very dark brown. We believe the cause of this to be that the metal tweezers holding the enzymes slipped from its clamp overnight and fell into the solution, and the reaction was a darkened color.

At the end of each week, I graph the voltage v current density, power density v current density, and power density v time of each graph. During last run of the fuel cell, we have taken out some of the solution in order to inspect it's color, and to make up for the loss in volume we added some more buffer and glucose. I accidentally added too much, but in the end it lengthened the lifetime of the fuel cell to almost two days from the former record in our lab. This made it apparent that our past fuel cells weren't lacking in stability, but in glucose to react with. We had restricted the initial glucose amount to 50 mg to keep it relevant for medical application, but from now on, we will be adding droplets of glucose into the solution (also corresponding with the body's own constant production of glucose) which should make our fuel cell last longer and simulates how it will react with the body more closely.

Its so fun to interpret the data from the fuel cell - I love being able to figure out what we can do to make the process as smooth and effective as possible, especially when my suggestions show good results. The one thing I would change about my lab is the quality of technology available, which is ironic since it's a tech school. Recently, our FTIR broke, which means we cannot characterize our carbon nanotubes to see if soaking the CNTs in GOx actually implants GOx onto the nanotube.

Still, this has been an incredible opportunity and I'm so grateful to be working in this lab. Within this next week we hope to try out two fuel cells, and hopefully we get good results!