A report on an experiment I did of doing electrophoresis with proteins

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FIG. 18: The above graph shows the intensities of the Coomassie stains as a function of the scaled protein mass in arbitrary
units along with an estimate of the errors in the intensities. This shows the problems of stalling at higher masses and a sharp
drop of the sensitivity at the lower ends. It also shows the best-fit straight line of 1.31932 × 10 6 x + 1.9090 × 10 6 that one gets
on dropping the lowest mass from the data.
• A similar experiment as above was done with the protein BSA (Bovine Serum Albumin) and this was commercially
bought. Hence in this case can know with greater confidence the amount of protein present in the sample
but running of the gel gave spurious bands and hence brought in the doubt that the commercial protein isn’t
so pure.
Further the staining data on BSA seemed to show some unnaturalness. Under the expectation that the efficency
of doing the experiment increases with time only the last 2 runs of doing electrophoresis on a dilution series
with the BSA are <strong>report</strong>ed in the follwing table and taking two rectangles from each gel as for Actin.
Run and selection 12µg 6µg 3µg 1.5µg 0.75µg 0.375µg
BSA Gel 1, rectangle 1 2.48778 × 10 6 2.44266 × 10 6 2.13022 × 10 6 2.01492 × 10 6 1.94225 × 10 6 1.62661 × 10 6
BSA Gel 1, rectangle 2 2.7648 × 10 6 2.78381 × 10 6 2.39877 × 10 6 2.29921 × 10 6 2.41803 × 10 6 1.82157 × 10 6
BSA Gel 2, rectangle 1 3.13856 × 10 6 2.87085 × 10 6 2.43379 × 10 6 2.4663 × 10 6 2.34672 × 10 6 2.06325 × 10 6
BSA Gel 2, rectangle 2 3.04063 × 10 6 2.83565 × 10 6 2.36599 × 10 6 2.39677 × 10 6 2.39455 × 10 6 1.90973 × 10 6
Mean∼ 2.85794 × 10 6 2.73324 × 10 6 2.33219 × 10 6 2.2943 × 10 6 2.27539 × 10 6 1.85529 × 10 6
Standard Deviation ∼ 253878.2709 170600.68982 119048.07566 171873.0588 194046.06649 157831.12494
TABLE II: Intensities and the averages and the standard deviations for the same masses of BSA in various trials
Fitting the function A x n
n = 0.197972.
on the above averaged points for BSA the values gotten are A = 2.95005 × 10 6 and