September 25th Post :)

Greetings to all my fellow Biominds companions!

Up to the moment research has begun and it has proven to be a little troublesome in some ways. I will get to those issues a little bit later.

I have already begun using the Apollo free radical analyzer and I am currently practicing and familiarizing myself with its usage. This machine has the ability to measure the presence of different free radicals dissolved in solution. The most common ones that are studied are NO^-, O₂, and H₂S.

In my case, I will be using the machine for sole purposes of studying the levels of H₂S. The machine itself functions in a fascinating way. The molecules of H₂S that are dissolved in solution, pass through a membrane that is permeable for H₂S only. Once inside the electrode, the H₂S is oxidized to HS^-; furthermore, for each molecule of H₂S that travels across the membrane, 2 electrons are produced and registered by the electrode. On the computer screen this will register a signal, typically measured in microamperes but that can obviously vary depending on the experiments conditions.

I will photograph the equipment in order to help you visualize what I am describing J    !

Up to the moment I have had 50% (3) of progress in my research. I understand the workings of this complex machine but there are procedures that must be done before starting any experiment. One of these procedures is the preparation of the reactive and buffers that I will be using. Since I am “building off” my research from last semester then all the materials are essentially the same. Some minor variations that must be taken into account are that each reactive must be degasified and purged with nitrogen. This is to ensure that no oxygen is present in the reaction (the sulfhemoglobin reaction in catalyzed by peroxide; this reaction could be catalyzed by oxygen but I will not venture into that just yet!). Usually the buffers are degasified and purged with nitrogen a total of three times.

A problem that I have had is that the permeable membranes that cover the electrodes of the Apollo Free Radical Analyzer have been breaking. Since the membrane is so sensitive; any tear or hole in it will cause the receptor signal to veer off to high levels without stabilizing. This problem has delayed the progress of my experiment; new membrane sleeves have been ordered and should arrive on Monday (hopefully !!!). Once they arrive I will install them on to the H₂S sensor and perhaps get this show on the road J.

~ by chrismolini on September 25, 2008.