Total Protein and Albumin Estimation

Question 1

Functions of proteins (introduction)

Answer 1

• structural
• catalyse reactions
• protection
• maintain oncotic pressure
• hormonal
• carrier proteins
• storage

Question 2

Total proteins (introduction)

Answer 2

• amino group from one aa combines with carboxyl group of another to give peptide bond
• joined together directly or through a single carbon or nitrogen

Question 3

Biuret method (introduction)

Answer 3

• colour dependant on peptide bond number
• peptide bonds react w/ copper in alkaline solution to give purple coloured chelate
• colour produced at 540nm is proportional to concentration

Question 4

Albumin (introduction)

Answer 4

• synthesised in liver
• synthesis increases in protein loss
• binds and transports compounds such as calcium, thyroid hormones, bilirubin, drugs

Question 5

Albumin method (introduction)

Answer 5

• acts as cation to bind anionic dyes at pH 4.2
• albumin and BCG reagent are allowed to bind at pH 4.2
• absorbance is determined at 628nm

Question 6

Define accuracy (results obtained and accuracy)

Answer 6

• how close a measurement is to actual true value

Question 7

Causes of inaccuracy and how to improve (results obtained and accuracy)

Answer 7

• incorrect pipetting, incorrect timings and other human errors
• multiple measurements, choice of equipment that reduces systematic errors

Question 8

Equation of albumin (results obtained and accuracy)

Answer 8

• concentration of unknown = (absorbance of unknown/absorbance of standard) x standard concentration

Question 9

QC ranges for total protein and albumin

Answer 9

• total protein QC range: 55-65 g/L

- albumin QC range: 35-45 g/L

Question 10

Elevated total protein

Answer 10

• inflammations or infections (such as viral hepatitis B or C, HIV)
• bone marrow disorders (such as multiple myeloma or Waldenstrom’s disease)

Question 11

Low total protein

Answer 11

• bleeding
• liver or kidney disorders (such as glomerulonephritis)
• malnutrition
• malabsorption conditions (such as coeliac disease or inflammatory bowel disease)
• agammaglobulinemia (blood not having enough of globulin, affecting strength of immune system)

Question 12

Elevated albumin (hyperalbuminemia)

Answer 12

• may indicate dehydration and severe diarrhoea

Question 13

Low albumin (hypoalbuminemia)

Answer 13

• infection
• inflammation (due to sepsis, surgery, or other conditions)
• inflammatory bowel disease
• kidney disease
• liver disease (such as cirrhosis, fatty liver disease, liver cancer or hep A,B or C)
• poor nutrition
• thyroid disease