Determination of beta-lipoproteins in blood serum

Laboratory diagnostics and determination
Fasting for 12-14 hours prior to collection. Ingestion of water or calorie-free liquids is permitted. The blood must be collected under standard conditions, in a sitting position.


 * 1) Electrophoretic (more precisely) — LDL is found in the electric field of &beta;–globulins
 * 2) By protein (apoprotein) concentration (indicative)

&beta;-lipoproteins are LDL lipoproteins: They form the nucleus (cholesterol esters, triglycerols) and the phospholipid and protein envelope: Apoprotein B-100

Principle
Heparin activates lipase to release lipoproteins from lipids. The released protein produces a clot with calcium, which we measure photometrically.

Equipment
Test tubes, pipettes, cuvette, spectrophotometer

Chemicals
0,025 mol/l solution of CaCl2, 10 g/l heparin

Method

 * 1) Pipette into the tube: 0.1 ml of blood serum, 0.1 ml of heparin, 4 ml of CaCl2
 * 2) Wait 10 minutes.
 * 3) To be measured spectrophotometrically at &lambda; = 650 nm in relation to distilled water (reference sample)
 * 4) Calculation: c = A. 9,25	 (g/l) 9.25 correction factor

Physiological parameters: 3,5-5,5 g/l

&beta;-lipoprotein disorders
↑ Elevated values: obesity, atherosclerosis, familial hyperbetalipoproteinaemia associated with insulin resistance (diabetes mellitus), hypothyroidism, fish eye disease, hypercholesterolaemia ↓ Decreased values: abetalipoproteinaemia, hypobetalipoproteinaemia, hunger, hyperthyroidism, pregnancy