Total Protein

Question 1

Measurement Principle:

Answer 1

Biuret Method

Question 2

Reference method:

Answer 2

kjedahl

Question 3

Reagents:
Monoreagent:

Standard

Answer 3

Monoreagent (alkaline medium):
Rocher's salt
Alkaline copper sulfate
NaOh
KI tartrate

Question 4

Proteins in the sample are made to react with _____ in an _______ (NaOh gives alkalinity). Interference are inhibited by _______ (a stabilizer). The final product ______ will give ______ color

Answer 4

Cu++ sulfate
alkaline medium
KI tartrate 
protein- Cu++ complex
blue-violet

Question 5

Intensity of color refers to the _____ reacted by the reagents. The more the intense the _____ coloration is, the more peptide bonds are detected. There should be atleast _____ present in the sample to be detected by biuret method

Answer 5

number of peptide bonds
blue-violet
2 peptide bonds

Question 6

Assay procedure:

Wavelength:
Temperature:

Answer 6

Wavelength: 550 nm, 546 nm
Temperature:25 - 37C

Question 7

1st step:

Answer 7

Determine the reagent blank absorbance

Question 8

Mix and incubate for ____ at 25C or _____ at 37C. Read the absorbance against reagent blank

Answer 8

30 mins

10 mins

Question 9

Computation:

Answer 9

g/dL = 4 x SA sample/SA standard

Question 10

Conversion factor:

g/dL –> g/L =
g/L –> g/dL =

Answer 10

g/dL –> g/L = 10

g/L –> g/dL = 0.1