04/03/13

                During this recent Wednesday, I went to my internship and was tasked with making a new group of buffers that my mentor would use in her later capillary electrophoresis test-runs. This time, she had me mix up five different buffers using 5 different powdery (solid) components: 6-phosphoneohexanoic, 1.10 decyldiphosphonic, n-phosphonomethyl glycine, aa, and COO. Using a balance beam, I measured out precisely the indicated grams and afterwards, mixed each of the 5 separate beakers with the liquid mixture tris. After all this, I then put the beakers one by one on top of a hot-plate magnetic stirrer device in order to mix fully dissolve the powdery components into a liquid solute. This was my first time both seeing and using this particular device and thus I was greatly amazed. Although there is not much to the  instrument--the left knob controls the stirring rate and the right knob controls heating--I found it to be an extremely useful device that could be used in a variety of situations in the laboratory. First, I added a small magnetic stir bar in the mixing solution. Since glass doesn't affect a magnetic field and most chemical reactions take place in glassware (ie: beaker), magnetic stir bars work well in almost all circumstances. However, the downfall is that the limited size of the bars restricts the effect of the instrument to relatively small (ie: under 4 liters) experiments. For larger volumes, another sort of stirring device is needed. This said, I was asked to make buffers with a volume of 3 liters so the stirring bar proved extremely helpful to me. After I had done all this, my next step was to set all of the buffers to the pH value of 7 (given to me prior from Yolanda, my mentor) using the methods used during my last internship before spring break.

Today unlike my last time here, I found myself working hard until the very end, trying to accomplish everything that I had been assigned. Although that meant standing up for the entire 3 hours, I fully enjoyed yet another day in the lab. I was able to experience first-hand, like any typical scientist, truly how fast time passes by when fully engrossed with one's laboratory procedures. I have yet to actually see or put my prepared solutes/substances in the capillary electrophoresis machine, but I am hoping that within the next couple of weeks, the opportunity will come up.

Above is a short clip of the magnetic stirrer that I very much enjoyed using.