SU1402932A1 - Method of determining mannitol content in products of mannitol production - Google Patents

Abstract

The invention is in the field of analytical chemistry and can be used in the food and medical industry for the quantitative determination of mannitol by thin layer chromatography. The goal is to increase the accuracy of quantification of mannitol and reduce the analysis time. A saturated solution of 2,4-dinitrophenylhydrazine in acidic medium is added to the weighed portion of the initial solution (mother liquor) of the mannitol production. The mixture is heated until the reduction of hydrazones, then cooled and filtered. The obtained filtrate is extracted with an organic solvent and diluted with water to achieve a concentration of 0.1-0.5%. The sample is applied to the plate and the mixture of ztanol, acetic acid and water is zoned in a volume ratio of 60: 0.25: 5. The amount of mannitol is determined by comparing the sample spot and standard solutions visually or using a densitometer, table 2. with (L

Description

1C

about him

: The invention relates to analytical chemistry and can be used in the food and medical industry for the quantitative determination of mannitol by thin layer chromatography (those).

The purpose of the invention is to improve the accuracy of quantification of mannitol and reduce the analysis time. The method is carried out as follows.

A saturated solution of 2,4-dinitrophenylhydrazine (DNPH) IB is added to the weighed portion of the initial solution (mother liquor) in an acidic medium. The mixture is heated to form hydrazones, then the mixture is cooled and filtered. The obtained filtrate is extracted with an organic solvent and diluted with water to achieve a concentration of 0.1-0.5%. The sample is applied to the plate and eluted with a mixture of ethano-PA, acetic acid and water in a volume ratio of 60: 0.25: 5. The amount of mannitol is determined by comparing a sample and a spot of a sample and standard plants visually or with a densitometer.

I And p and me R 1. To a portion of the mother liquor (2.0-2.5 g), add 2 ml of a saturated solution of DNPH in 2 N, HCl. The mixture is heated at 80-85 ° C for -10 min, which makes it possible to isolate reducing compounds 3 in the form of hydrazones. The solution is cooled: “filtered. The precipitate is washed with a total volume of solution of 8-10 ml. The filtrate is extracted with 5 ml of ethyl acetate. After separation of the extract, the aqueous solution is transferred to a 100 ml measuring flask and adjusted to the mark with distilled water to obtain a mannitol concentration of 0.1-0.5%. Next, 1-2 µl of the test solution is chromatographed on Silufol plates in the eta-1nol system - acetic acid - water (60: $ 0.25: 5). The sample is applied to the plate S of the middle part of the starting line in parallel with 4 standard mannitol solutions with a concentration of O, 1-0.5%. "Mannitol periodate and benzis are shown, the spot area is determined (in square millimeters) and the graphics plotted over the areas of the standard solutions spot find the concentration of mannitol in the test solution. Standard opshbka definition of 1015%, which corresponds to the accuracy of the method of those.

To assess the accuracy of the method, 7 weights of a 10% aqueous solution of mannitol were analyzed. The results of the analysis and their static processing are given in Table 1, where n is the number of parallel definitions; x - ± d. x confidence interval of the mean value of the concentration of the analyzed component; P - confidence probability.

Since the student coefficient calculated experimentally (0.381) turned out to be less than the tabular one (2.45), the TLC method for the quantitative determination of mannitol should be considered accurate.

EXAMPLE: Mme R 2. A portion of the queen in the amount of 2.5776 g is taken on an analytical balance in a pre-weighed glass, 2 ml of a saturated solution of DNPH in 2 N, HCl is added. The mixture is heated at 85 ° C. for 5 minutes, cooled in air and filtered through a folded filter. The precipitate is washed on the filter with distilled water so that the total volume of the solution does not exceed 10 ml. Next, the filtrate is extracted with 5 ml of ethyl acetate. After separation in the separating funnel of the extract, the aqueous solution is transferred to a 100 ml volumetric flask. The contents of the flask are made up to the mark with distilled water.

For analysis by TLC, 1 μl of the resulting solution is used. The test solution is applied in the middle part of the starting line in parallel with standard solutions of mannitol with a concentration of 0.1-0.5%. The plate is placed in the chromatobox with the system ethanol - acetic acid - water (60: 0.25: 5).

After the eluent has reached the front line, the chromatogram is dried in air, sprayed sequentially with a saturated aqueous solution of potassium metaperiodate and an ethanol-acetone solution of benzene. Mannitol gives yellow spots on a blue background. The spot area is then determined and a plot of the concentration of the spot mannitol spot is plotted. Since at a mannitol concentration of 0.1-0.5%, a direct dependence of the spot area on the concentration is observed, it is expressed directly.

314U2932

passing through the origin. the initial solution on a plate. Using the plotted graph, the elution with a mixture of solvents will give the content of mannitol in the weighed portion of the mother liquor. Results of determination

and detecting mannitol stains with reagents, characterized in that, in order to increase the accuracy of the amount of mannitol determination and reduce the analysis time, a sample of the initial solution is applied to excess mannitol concentrations in the about-Q plate treated with an excess of 2.4 samples not treated with DNPH, 43,6 ± -dinitrophenylhydrazine in an acidic environment,

the precipitated precipitate is removed, unreacted 2,4-dinitrophenylhydrazine is extracted with organic solution. The formula of the invention is 15 with a solvent and diluted with water until the mannitol concentration reaches 0.1-0.5%,

mannitol in the end liquor are given in table 2.

Confidence interval average

3.00%, and after treatment with DNPH, 33.5 ± 13.14%.

The method for determining mannitol content in mannitol intermediate products, including application of pro- duction as a solvent, uses a mixture of ethanol, acetic acid and water in a volume ratio of 60: 0.25: 5,

Table 1

Claims (1)

The claims of the invention ^ A method for determining the mannitol content in mannitol intermediates, including applying a sample of the initial solution to the plate, eluting it with a mixture of solvents and detecting mannitol stains with reagents, characterized in that, in order to increase the accuracy of the amount of mannitol determination and reduce analysis time, a sample of the initial solution before application the plate is treated with an excess of 2,4-dinitrophenylhydrazine in an acidic medium, the precipitate is removed, the unreacted 2,4-dinitrophenylhydrazine is extracted with organic skim solvent and diluted with water until the mannitol concentration of 0.1-0.5%, and as the eluent a mixture of ethanol, acetic acid and water in a volume ratio of 60: 0.25: 5, Table! Found mannitol,% η x + yx at P = 0.95,% 8.4 10.5 9,4 9,4 - - 4 9.4 + 1.37 8.4 9.1 9.0 And 9 10.7 9.0 6 9.7 + 1.40 h 9.3 10.5 10,4 10.6 10.6 10.7 6 10.4 + 0.20 13.0 8.5 10.9 - - - 3 10.8 + 3.59 10.7 12.0 9.1 - - - 3 10.6 + 3.60 9.2 9.0 - - - - 2 9.1 + 1.26 9,4 8.6 - - - - 2 9.0 + 5.13 Table and 2 Without DNFH processing FROM DNFH treatment Hitch g Found mannitol % Hitch, g Found mannitol,% 2.7616 36.52 - - 1,7013 33.45 28.38 35.00 1.8576 46.41 49.21 - 2.4812 39.28 40.93 35.45 2,2473 42.58 45.66 51, 00 2,2107 33.14 31.21 - 2,6252 40.72 36.48 40.41 2.7756 28.90 31.69 - 2,1887 48.83 44.79 - - - - 2,5776 46.83 37.48 - . - - '- . ATTENTED Order 2851/34 Circulation 847 Subscription Custom polygon. ave, city of Uzhhorod, st. Project, 4