Missed Weeks :(

Last week (March 5), I was unable to go to RPI because I was sick. This week (March 12), my mentor was on spring break, so I could not go this week, either! For the next two weeks (March 19 and March 26), I will be on spring break, so I will not be going to RPI. I can't wait until I can go back and continue my research!

More PBS and Data!

This Tuesday (February 26th), I ventured to RPI to continue my work in the lab. This week, I was again tasked with making PBS solution. As I explained in a previous entry, PBS (phosphate buffered saline solution) can be used to dialyze protein solutions. PBS is made by combining 15.52 mL of 1M K₂HPO₄, 4.48 mL of 1M KH₂PO₄, 2 L of distilled water, and 11.6 g of NaCl. After mixing these contents, I had to raise the pH to 7.4 using 1M NaOH base. After creating a pH of 7.4, I filtered the PBS using a bottle-top filter with a vacuum attached, like the one shown below.

After finishing the PBS, my next job was to work with the data from the concentration experiment I helped set up last week. First, the organization of slides on the Origin program was different than the actual setup, so I had to convert the data to accurately represent its respective slide. Once I reorganized the data, I was able to run the program to create graphs and calculate the 1/kD and R2 values for each piece of data. Luckily, the experiment worked almost perfectly! Each of the graphs looked like the one shown below, which was the graph we predicted last week before the experiment was run. 

I looked at every graph and recorded the numbers of the graphs that did not seem to fit the data points as well as the others. I then copied the origin data twice into an excel sheet and sorted the data according to 1/kD value and R2 value. Most of the R2 were 0.9 or above, which means that the data followed the curve very well. I tried to find a correlation between the graphs with worse 1/kD values and worse R2 values, but there did not seem to be an obvious correlation between the two. I color coated the data in both sorting sets according to different R2 value ranges. There were no R2 values in the blue range! 

• Set 1- green- 0.95+
• Set 2- yellow- 0.9-0.95
• Set 3- red- 0.7-0.9
• Set 4- blue- less than 0.7

This coding allowed me to look for further correlation between 1/kD value and R2 value, but there still appeared to be no correlation between the two. 

I can't wait to work with the data more next week!