RAYTMANA-FRENKELYA METHOD — a colorimetric method of definition of activity of aspartate aminotransferase (ASAT) and alaninaminotranspherase (ALAT) in blood serum. Activity of these enzymes serves as additional diagnostic test at a number of diseases in blood serum; increase in activity of ASAT and ALAT in blood serum is observed at a myocardial infarction, diseases of a parenchyma of a liver, especially at hepatitises, at acute pancreatitis, diseases of kidneys, various myopathies, injuries of muscles, etc.
The method is offered by S. Reitman and S. Frankel in 1957 and is one of numerous modifications of a method of definition of ASAT and ALAT developed by F.Wro blewski. In the USSR this method is accepted as unified.
Principle. As a result of the reaction of transamination (see) catalyzed by ASAT it is formed oxalacetic to - that, in the reaction catalyzed by ALAT — Pyroracemic to - that (see. Aminotransferases ). Oxalacetic to - that in the course of definition is translated in pyroracemic, edges with 2.4 dinitrophenylhydrazine in alkaline condition are formed by the painted hydrazone; intensity of coloring of solution is proportional to quantity formed pyroracemic to - you also can be measured colorimetric (see. Colorimetry ).
Course of definition of activity of ASAT. Mix 0,1 ml of blood serum from 0,5 ml preheated to t ° 37 ° so-called substrate solution, for preparation-rogo for 29,2 mg alpha and keto-glutaric to - you and 2,66 g asparaginic to - you dissolve in the solution containing 1 mol of NaOH in 1 l (pH of the received solution shall be 7,4), and add to 100 ml phosphatic buffer solution in concentration 0,1 mol/l (pH of solution 7,4). Mix of blood serum with substrate solution incubate at 2 °37 ° within 60 min. Then add 0,5 ml of solution 2,4 of dinitrophenylhydrazine (19,8 mg dissolve 2.4 dinitrophenylhydrazines in 100 ml salt to - you, concentration a cut is equal to 1 mol/l), maintain within 20 min. at the room temperature. Add 5 ml of ShON solution to concentration of 0,4 mol/l, carefully mix and leave for 10 min. at the room temperature. Kolorimetrirut on the photoelectrocolorimeter at the wavelength of 500 — 560 nanometers (the green light filter) in a ditch with thickness of a layer of 1 cm against single check. Single test is prepared as well as experienced, but solution 2,4 of dinitrophenylhydrazine is added to an incubation.
Course of definition of activity of ALAT. Mix 0,1 ml of blood serum from 0,5 ml preheated to t ° 31 ° substrate solution, for preparation-rogo for 29,2 mg alpha and keto-glutaric to - you and 1,78 g of alanine dissolve as well as at preparation of substrate solution for definition of activity of ASAT, incubate at t°37 ° within 30 min. The further course of the analysis same, as well as during the definition of activity of ASAT.
Calculation of activity of enzymes is made according to the calibration schedule, as standard solution use solution of pyruvate of sodium (110 mkg/ml) that corresponds to concentration pyroracemic to - you are the 88th mkg/ml (1 µmol/ml); prepare a number of the cultivations of standard solution containing 0,05; 0,10; 0,15; 0,20 and 0,25 µmol pyroracemic to - you, to the Crimea flow 0,5 ml of solution 2.4 of dinitrophenylhydrazine, further tests process as well as experienced.
Activity of enzymes express in micromoths pyroracemic to - you, the blood serum formed 1 ml at an incubation in 1 hour at t°37 ° — µmol/hour • ml; in SI units — nmol / (with • л).
Normal amounts of activity of ASAT and ALAT are equal in blood serum respectively 0,1 — 0,45 and 0,1 — 0,68 µmol pyroracemic to - you on 1 ml of blood serum in 1 hour of an incubation at t ° 37 °.
See also Blood , methods of a research.
Bibliography: Biochemical methods of a research in clinic, under the editorship of A. A. Pokrovsky, page 112, M., 1969; Todorov Y. Clinical laboratory trials in pediatrics, the lane with bolg., page 873, Sofia, 1968; Reitman S. Frankel S. A colorimetric method for the determination of serum glutamic oxalacetic and glutamic pyruvic transaminases, Amer. J. clin. Path., v. 28, p. 56, 1957.
L. M. Pimenova.