Protein Assays

Question 1

What are the different types of protein assays?

Answer 1

Dye binding = total protein concentration (Biuret, Bradford)
Immunological = concentration of a specific protein
Mass Spectrometry

Question 2

What are the uses of protein assays?

Answer 2

Comparing concentration of a specific protein relative to total protein concentration
Determining protein concentration in food
Determining protein concentration in urine

Question 3

What are protein assays based on?

Answer 3

Chemical reactions that can be measured

Question 4

What chemicals are in a biuret reagent?

Answer 4

Sodium hydroxide
Copper sulphate
Potassium sodium tartrate

Question 5

What colour will the sample turn if there is no protein present in a biuret reaction?

Answer 5

Blue

Question 6

What colour will the sample turn if there is protein present in a biuret reaction?

Answer 6

Violet - Copper sulphate binds to peptide bonds in proteins