Serum protein electrophoresis
(SPEP)

(SPEP) is an easy, inexpensive method of separating proteins based on their net charge, size, and shape.

Sample type:

• Urine samples or, cerebrospinal fluid (CSF).

• Serum is obtained by collecting a blood sample.

Uses:

• Used to identify patients with multiple myeloma and other serum protein disorders.

• Separates proteins based on their physical properties, and the subsets of these proteins are used in interpreting the results.

Precaution:

• Avoid prolonged application of a tourniquet.

• Avoid hemolysis and lipemic serum.

• Avoid blood from the side of the I/V infusion which will lower the result.

• Drugs like anabolic steroids, androgens, dextran, growth hormone, progesterone, and insulin increase the protein level.

Interfering factors:

Characteristics of the ion or molecule itself, the environment (buffer) in which the molecule or ions are being studied, and the applied electrical field. These factors specifically affect the migration rates of molecules in the sample during electrophoresis.

Pre analytical errors:

• Errors may occur in:

1. Error in the sample

2. The electrophoretic system

3. And the nature of proteins itself.

4. The electric field,

5. Temperature of the system,

6. PH of the ions,

7. Concentration of buffer.

Corrective action:

Correctly adjust all system component, including:

• Electricity, PH, temperature and buffer.

Post analytical errors:

1- Failure to report test results,

2-delay in reporting,

Reference rang:

• Total protein: 6.4 to 8.3 (g/dL)

• Albumin: 35 to 50 g/L

• Alpha-1 globulin: 1 to 3 g/L

• Alpha-2 globulin: 6 to 10 g/L

• Beta globulin: 7 to 12 g/L

• Gamma globulin: 7 to 16 g/L