Science Buddies: "Ask an Expert"

Hi! I am currently trying to conduct an experiment to research the impact of a food supplement in its relation to protein contents in egg whites. I have decided to isolate Albumin from the egg whites using Ammonium Sulfate and Acetic Acid to then centrifuge the solution to separate the protein from the egg. My question is I have no idea how to quantify how much protein was extracted and what control group I should use as a reference. If anyone is able to help me it would be gladly appreciated!

Hi C_Gates,

There is a Science Buddies project that uses the Bradford assay to determine protein concentrations:

https://www.sciencebuddies.org/science- ... nt#summary

You may find the background, bibliography and procedure sections of the project useful in your work.

Some general information about various protein assays can be found here:

https://www.thermofisher.com/us/en/home ... ssays.html

Some of protein assays (like the Bradford assay) use a spectrophotometer to measure the color intensity of test solutions. The intensity is proportional to protein concentration. If you don't have access to a spectrophotometer, you still may be able to conduct an assay. You could test a pure protein sample to get a color change with the Bradford reagent. You could then make several dilutions of the original solution to get a range color intensities. Visual comparison of unknown samples with the known dilution range would give you an idea of the protein concentration.

Based on the information you posted, I'm not sure you need a control group for your experiment. You would need a purified protein from egg white for calibration of your assay (spectrophotometer or visual).

I hope this helps. Please ask again if you have more questions.

A. Norman