FOLIN METODA (K. O. of Folin, the Swedish physiologist and the chemist, 1867 — 1934) — methods of quantitative definition in blood of the general content of amino acids, concentration of uric acid and glucose; have great clinicodiagnostic value.
Folina a method of definition of the general a soderzhaniiya of amino acids in blood. The method is offered in 1922.
Principle of a method: amine
of acid (see) with | 5-naphthoquinone-sul-fokislym sodium form colored compound, intensity of coloring of solution is proportional to the content of amino acids and can be measured colorimetric (see Colorimetry).
Course of definition. For sedimentation of proteins of 1 ml of a blood plasma mix from 7 ml of a distilled water, 1 ml of 10% of solution of sodium tungstate and 1 ml 2/3 N of solution a chamois to - you. Stir up, then filter or centrifuge. At the same time prepare standard test: to 1 ml of standard solution of glycine (37,5 mg of glycine and 0,14 g of sodium benzoate dissolve in 100 ml 1 N of solution salt to - you; 1 ml of standard solution contains 0,07 mg of nitrogen) add 3 ml of a distilled water and 1 ml of 2,5% of sodium carbonate. And to standard test add to 5 ml of a filtrate (the pilot test corresponding to 0,5 ml of a blood plasma) on 1 drop 1% of solution of phenolphthalein; pilot test titrate before emergence of pink coloring 2,5% solution of sodium carbonate (3 — 5 drops). Then add 1 ml to pilot and standard tests freshly cooked (not earlier than in 1 day prior to the use) 0,5% of solution (Z-naftokhinon-sulfokislogo sodium. Slightly stir up and leave both test tubes on 19 — 30 hours in the dark. Then add 1 ml of solution to both test tubes acetoacetic to - you (to 100 ml of 50% of solution acetic to - you add 100 ml of 5% of solution of sodium acetate), on 1 ml of 4% of solution of sodium thiosulphate and on 7 ml of a distilled water. Stir up, kolorimetrirut at the wavelength of 470 nanometers against the single test containing mix of reactants.
Calculation of content of amino-acid nitrogen (mg / 100 ml) is done on a formula:
Eop-0,07 - 200 Eats
where Eop — a zkstinktion of pilot test, Eats — a .zkstinktion of standard test, 0,07 — concentration of nitrogen in standard solution (mg/ml), 200 — coefficient of recalculation on 100 ml of blood serum.
Amino-acid nitrogen normal makes about 25% of all fraction of residual (nonprotein) nitrogen in blood (see residual nitrogen).
Increase in content of amino-acid nitrogen is observed at the exudative diathesis, a spasmophilia, diseases of a liver, a fenilketonuriya, diseases which are followed by fever, tumors, etc.
Folina a method of definition of uric acid in blood. The method is offered in 1922.
Principle of a method: uric acid (see) in alkaline condition recovers phosphatotungstic to - that with formation of the connection painted in blue color; intensity of coloring of solution is proportional to concentration uric to - you also can be measured colorimetric.
Course of definition. For sedimentation of proteins or a blood plasma add to 4 ml of serum 4 ml of 10% of solution of sodium tungstate, 28 ml of a distilled water and 4 ml 2/3 N of solution a chamois to - you. Stir up, in a few minutes filter. Place 20 ml of a filtrate in a volumetric flask (25 ml), the corresponding 2 ml of blood serum, 1,5 ml of 40% of solution of sodium carbonate and 0,5 ml of a phosphatotungstic reactant (10 ml of 10% of solution of sodium tungstate, 80 ml of 85% of solution phosphoric to - you and 750 ml of a distilled water), mix, boil not less than 2 hours with the reflux condenser, after cooling add water up to 1 l, bring to 25 ml a distilled water. At the same time prepare standard test. For preparation of the main standard solution dissolve 0,2 g uric to - you, 2 g of disodium phosphate and 1 g of monosodium phosphate in 600 ml of a warm distilled water (60 °), after cooling bring water to 1 l. Working solution is prepared by cultivation of the main solution in the ratio by 1:2, 1 ml contains 0,1 mg uric to - you. Add
1,5 ml of 40% of solution of sodium carbonate and 0,5 ml to 1 ml of working standard solution - a phosphatotungstic reactant, bring to 25 ml a distilled water. In 10 min. kolorimetrirut both tests against single, containing mix of reactants.
Calculations of contents uric to - you (^иг/100 ml) are made on a formula:
Eop - ODES • 50
where Eop — a zkstinktion of pilot test, Eats — a zkstinktion of standard test, 0,1 — contents uric to - you in standard test (mg), 50 — coefficient for recalculation of contents uric to - you on 100 ml of blood serum.
In 2 — 3 days prior to the analysis of the patient shall keep to a milk and vegetable diet.
Contents uric to - you in blood, defined by means of F. the m, normal makes 2 — 5 zhg/100 ml. Strengthening uric to - you in blood observe at disturbances of exchange of purine bases, nek-ry diseases of kidneys (nephrite, nefroza, tuberculosis of kidneys), at a decompensation of heart failure, lead poisoning, nek-ry diseases of blood, etc.
Folin — By a method of definition of glucose in blood (H. Wu, the Chinese biochemist, 1893 — 1959). The method is offered in 1919
P r and N of c and and a method: glucose (see) during the heating in alkaline condition recovers cupric tartrate in copper oxide, in turn, recovers edges fosforno-molibde - new and tungsten to - that with education molybdenic blue, intensity of coloring of solution is proportional to amount of glucose and can be measured colorimetric.
Course of definition. For sedimentation of proteins to 1 ml of the blood taken with anticoagulant (sodium fluoride) flow
7 ml of a distilled water, 1 ml 2/z N of solution a chamois to - you, 1 ml of 10% of solution of sodium tungstate, stir up and in 15 min. filter. To 2 ml of a filtrate, the corresponding 0,2 ml of blood, in a volumetric flask (25 ml) add 2 ml of a copper-sodium reactant of Folin — By (40 g of anhydrous sodium carbonate dissolve in 400 ml of the bidistilled water, add 5 g wine to - you and 4,5 g of the crystal copper sulfate dissolved in 50 ml of water bring water to 1 l). The flask is placed in the hot water bath, in 6 min. cooled, then quickly add 2 ml of a phosphorus-molybdenum-tungsten reactant (35 g molybdenic to - you, 5 g of sodium tungstate, 200 ml of 10% of solution of caustic soda and 200 ml of the bidistilled water boil within 1 hour, охлаждают^, add 125 ml of 85% of solution phosphoric to - you, bring to 500 ml), add water up to 25 ml, mixed. At the same time prepare standard test. For preparation of the main standard solution dissolve 1 g of anhydrous glucose in 100 ml of 0,25% of solution of the benzoic to - you; 1 ml of the main standard solution contains 10 mg of glucose. Working solution is prepared by cultivation of the main solution by 100 times; 1 ml of working standard solution contains 0,1 mg of glucose. For preparation of standard test of 2 ml of working standard solution process the same as pilot test. Both tests kolorimetrirut against single, containing mix of reactants.
Calculation of content of glucose in blood (mg / 100 ml) is done on a formula;
Eop • 0,2 • 500
where Eop — an extinction of pilot test, Eats — an extinction of standard test, 0,2 — the content of glucose in standard test (mg), 500 — coefficient for recalculation on 100 ml of blood.
FOLLIKULOSTIMULIRUYUSHCHIYA HORMONE 365
the Content of glucose in blood during the definition by this method normal makes 70 — 110 mg! 100 ml. However in clinic the increasing place is taken by definition of glucose by a glyukozo-oksidazny method — more specific and exact (see Gorodetsky methods).
Definition of concentration of glucose in blood has important diagnostic value, especially at a diabetes mellitus. The iperglikemiya (see) can be observed at acute pancreatitis, diseases of a liver, hypersecretion of nek-ry hormones at a thyrotoxicosis, Itsenko's disease — Cushing, etc. The hypoglycemia (see) can take place at nek-ry inf. diseases, a hypothyroidism, an addisonovy disease, poisonings with phosphorus, benzene, etc.
See also Blood, methods of a laboratory research.
Bibliography: D to P. and
Peunesku B. zhordzhesk. Biochemical methods of the diagnosis and a research, the lane from Romanians., Bucharest, 1963; F about 1 i and O. of A system of blood analysis, J. biol. Chem., v. 38, p. 81, 1919, v. 51, p. 377, v. 54, p. 153, 1922. L. M. Pimenova.