Serum biochemical parameters TOTAL Protein assay Biochemistry Clinical practice CLS 432 Dr. Samah...

Serum biochemical parametersTOTAL Protein assay

Biochemistry Clinical practiceCLS 432

Dr. Samah KotbLecturer of Biochemistry

2015

What do you know about liver function

• 1. Total and conjugated bilirubin • 2. ALT• 3. AST• 4. Total protein• 5. GGT• 6. ALP • 7. 5 -nucleotidase′• 8. Albumin• 9. prothrombin time

Liver Function tests

• Total protein was estimated according to the method of (Burtis A and Koller A ., 1999) , Colorimetric method.

Principle

• Proteins give an intensive violet –blue complex with copper salts in an alkaline medium. Iodide is included as an antioxidant.

Principle

• The intensity of the color formed is proportional to the total protein concentration in the sample.

• Total protein Standard : Bovine serum albumin standard (7g/dL)(70 g/L).

• Biuret reagent: R1

• Sodium Potassium tartrate (21 mmol/L)

• Sodium hydroxide (0.75 mol/L)

• Potassium iodide (6 mmol/L)

• Cupric Sulfate (6 mmol/L)

Reagents

• 1- 1 ml of Biuret reagent was added into both unknown test and control tubes, then 0.02 ml of serum were added to unknown.

Procedure

• 2- 0.02 ml of Bovine albumin primary standard and 1 ml of Biuret reagent were added into standard tube, 1 ml of Biuret reagent was added into blank tube.

• 3- The contents were mixed well, incubated at 37°C for 5min, standard and blank tubes.

• 4- The absorbance read at 540 nm.

• 5- Blank was used for zero adjustment of standard, and the test.

• A sample • Concentration of protein ( g/dL) = x 7.0 • Where: A standard • A: absorbance of recorded sample• 7.0: Standard concentration

Calculation:

• Adults: 6.6-8.7 g/dL (66-87g/L).• Prematures: 3.6-6.0 g/dL (36-60 g/L).• Newborns : 5.3-8.9 g/dL (53-89 g/L)• Pregnancy: Concentration lowers from 69 to

61 g/L

Reference values