METHOD FOR EVALUATING ANTIOXIDANT POTENTIAL OF LOW-DENSITY LIPOPROTEINS (LDL)

摘要

FIELD: clinical biochemistry. SUBSTANCE: the present innovation deals with obtaining LDL out of blood serum due to depositing in the presence of heparin (200 U/ml serum) and manganese chloride (50 mM/ml serum) at 0 C, washing deposited LDL with 0.9%-sodium chloride solution, their dissolving in 1 ml 1 M-sodium chloride solution, measuring there protein concentration by the well-known Lowry method followed by addition of 0.5 ml ethanol to 0.25 ml LDL, shaking, addition of 0.25 ml ascorbic acid and 0.5 ml 10 N KOH (for samples' saponification). Then samples should be incubated in water bath at 70 C for 40 min and cooled, 2 ml heparin should be added followed by thorough 3- min-long shaking, superior hexane layer is transferred into other tubes to detect there concentrations of vitamins E and A due to spectrofluorimetric method. Wave length for retinol corresponds to Ex 340, Em 490 nm, for alphatocopherol - Ex 290, Em 334 nm. Results are expressed for vitamin E in mg/ml LDL protein, for vitamin A - in mcg/mg LDL protein. The innovation suggested provides higher information value, simplicity of the method, its shortened time for implementation and could be applied under conditions of clinical biochemical laboratories. EFFECT: higher efficiency of evaluation. 1 cl