# Prepare a series of standards diluted with 0.15 M NaCl to final concentrations of 0 (blank = No protein), 250, 500, 750 and 1500 µg/mL. Also prepare serial dilutions of the unknown sample to be measured.
# Add 100 µL of each of the above to a separate test tube (or spectrophotometer tube if using a Spectronic 20).
# Add 5.0 mL of Coomassie Blue to each tube and mix by vortex, or inversion.
# Adjust the spectrophotometer to a wavelength of 595 nm, using the tube which contains no protein (blank).
# Wait 5 minutes and read each of the standards and each of the samples at 595 nm wavelength.
# Plot the absorbance of the standards vs. their concentration. Compute the extinction coefficient and calculate the concentrations of the unknown samples.