SU1506338A1 - Method of quantitative analysis of tropaphene - Google Patents

Abstract

This invention relates to analytical chemistry, in particular, to the quantitative determination of tropaphene. In order to increase the detection sensitivity and simplify it, the solution of the analyzed sample in water is treated with 1,4- (2,4,5-trimethyl-1-sulfonate sodium cyclohexyl-3-amino) perhydroanthraquinone at a pH of 1.8-3.0. The resulting associate is extracted with chloroform, the extract is treated with an alkaline solution of borax, followed by photometric measurement of the resulting aqueous phase. The relative error in the determination of tropaphene in the substance and in the lyophilized powder does not exceed ± 1.65%, the sensitivity of the method is 15 times higher. 6 tab.

Description

The invention relates to a method for quantifying tropaphene, which may find application in control laboratories.

The purpose of the invention is to increase the detection sensitivity and simplify it.

Example 1. Definition of tropafen in substance. 1 ml of an aqueous solution of tropafen (0.25 mg per sample) is added to the separatory funnel, 8 ml of a universal buffer mixture with a pH of 2.75, 1 ml of a 0.1% aqueous solution of reagent and 10 ml of chloroform are added. The mixture was agitated for 3 minutes, then left to separate the phases for 10 minutes. After separation of the phases, the chloroform layer is transferred to a separatory funnel containing 10 ml of a 3.8% borax solution in 0.2N. sodium hydroxide solution, and shake for 10-15 seconds. After settling the phases, the colored alkaline solution is separated. The optical density of the colored foliar solution was measured using a KFK-2 photo-reflectorimeter (a light filter at 590 tlO nm, a cuvette of 20 mm). A 3.8% borax solution in 0.2 N was taken as a comparison solution. sodium hydroxide solution. Build a calibration graph.

8 separatory funnels are introduced at 0.1; 0.2; 0.4; 0.6; 0.8; 1.0 ml of standard solution of tropafen, in 1 ml of which 0.25 mg of the preparation is contained, then a solution of UBS (pH 2.75) is added to all separatory funnels

9 ml, 1 MP of a 0.1% reagent solution, 10 ml of chloroform each, and proceed as indicated above. Using the obtained values of optical density

9) 00 WITH

00

ti (Table 1). build calibration graph. Subjection to the Bouguer-Lambert-Beer law is observed within concentrations of tropafen (0.025-O, 25 mg / ml).

Using a calibration chart, determine the amount of preparation to be assayed. This method can be used to quantify tropaphene both in substance and in a lyophilized powder.

Example 2. Quantitative determination of tropaphene in a lyophilized powder. The content of one vial is 0.02 g quantitatively transferred to a 100 ml volumetric flask, dissolved in water and made up to the mark.

10 ml of chloroform, 8 ml of the universal buffer mixture (pH 2.75), 1 ml of the analyzed preparation and 1 ml of O, 1% reagent solution are added to the separatory funnel. Next, proceed analogously to example 1.

The calculation of the concentration of tropafen in the lyophilized powder can be carried out not only according to the calibration schedule, but also according to the following formula:

7 5-PA02925 U 100

 t lt g m

D

st

V - 0.02

where D is the optical density of the solution being analyzed; DtT optical density of the standard solution (0.79 with a content of 0.25 mg / ml, tropafen);

0,00025 - the content of tropafen in 1 ml of the standard solution; Vj (is the volume of the test solution,

taken for analysis:

VP is the volume, in which the tropafen sample is dissolved, taken for analysis; 0.02 - the amount of tropaphene in one

vial.

In tab. 2 shows the comparative assessment and results of the quantitative determination of tropaphene in a substance and in a lyophilized powder by known and proposed methods. I

In tab. 3 shows data on the dependence of the optical density on the pH of the universal buffer mixture (UBS).

From the results table. 3 it follows that the ionic associate of tropafen and the reagent is extracted in the largest quantities by chloroform at pH 1.8-3.0

Q

0

five

0

five

five

0

In further studies, a solution of a universal buffer mixture with a pH of 2.75 is used.

In tab. 4 presents data on the dependence of the optical density on the volume of O, 1% reagent solution.

From the data table. 4 it follows that in order to completely form an ionic association between tropaphen and the reagent, it is necessary to add 0.5-2 ml of O, 1% aqueous solution of a bright blue anthraquinone dye. In further studies, 1 ml of the solution of the indicated reagent is added.

It has been established that in order to achieve optimal conditions for the quantitative determination of tropafen, based on the interaction of the preparation with the acid bright blue anthraquinone dye, it is necessary to take 1-2 ml of a solution of tropafen containing in this volume 0.05-0.25 mg of this preparation ml. universal buffer solution with a pH of 2.75, 1 ml of O, 1% reagent solution and 10 ml of chloroform.

The data on the values of optical density after sample processing with solutions of various concentrations of sodium and potassium hydroxides containing 3.8% borax are given in Table. five.

From the data table. 1, it follows that more suitable for complete destruction of the ion associate of tropafen and dye are 0.15 n. - 0.25 n. sodium hydroxide solutions containing borax. Subsequently, 0.2 N is used. sodium hydroxide solution containing borax.

Results of a study of the effect of a borax amount of 0.2N. a solution of sodium hydroxide; ri the solubility of the dye liberated from the ionic associate is given in Table. 6

The data from the table. 6 indicate that the complete dissolution of the 0.2 d released from the ionic associate of the dye. sodium hydroxide solution is observed in the presence of 0.2 n. sodium hydroxide solution 3,4- 4,0% borax. The most reproducible optical density of the released dye is achieved when it is dissolved in 0.2 N. sodium hydroxide solution containing 3.6-3.8% borax. Subsequently, to dissolve the dye released from the ionic associate, the samples are treated with a 3.8% borax solution in 0.2N. sodium hydroxide solution.

It was established that in order to observe the direct dependence of the optical density of the dye on the quantity of the preparation, a sample containing up to 0.25 mg of tropafen should be treated with 0.5-2 ml of a 0.1% acidic solution .. : it is anthraquinone (1I (, 25 tropafen corresponds to i-D, 63-10 moles of this preparation). In 0.5-2 ml of a 0.1% solution of dye contain / 7, 12-10 - 2.8 10 the mole of this cranial body. Therefore, in the analyzed sample, tropafen and reagent should have a molar ratio of 1: 1.26–4.97.

The proposed method for the quantitative determination of tropafen is simpler in execution, eliminates the use of non-soluble solvents and toxic acetate of mercury oxide.

The proposed method is characterized with higher accuracy than the known one. The relative error in the determination of tropaphene in the substance and in the lyophilized powder by the proposed method does not exceed ± 1.65%, while the relative error in the determination of tropaphene in the substance and the lyophilized powder by a known method is 2.55%.

The sensitivity of the proposed method is 15 times higher in comparison with the substance known for analyzing tropafene in a substance.

The proposed method allows the determination of tropaphene not only in the substance and the lyophilized powder, but also in objects of biological origin.

Claims (1)

Invention Formula The method of quantitative determination of tropaphene, which means that, in order to increase the sensitivity of the determination and its simplification, the solution of the analyzed sample in water is treated with 1,4- (2,4,5-trimethyl-1-g. sodium cyclohexyl 3-amino) perhydro-anthraquinone at pH 1.8-3.0 and the resulting associate is extracted with chloroform, the extract treated with an alkaline solution of borax followed by photometry of the image of the aqueous phase. Table 1 Tropafen in substance Tropafen in lyophilized powder in vials on 0.02 g 0.396.67 X 99,200,0299.70 X 99.37 0.398.33 S 2, OA0.029.8.10 S 1.32 Table X 100.32 S 0.85 S 0.38 c, 9S 1, 05 A „,, 05 a 99.27-101.02 101.33 Sj 0.910.02 98.33f ,, s 2,530.02 101.33Ao, t2,550.02 a 96.65-101.75 The exact weight of tropafen (0.02 g), defined in the substance is suggested; method, dissolved in 100 ml} yuda, for analysis take 1 ml of the resulting solution. Table 3 Oh, 15 n 0.20 n. 0.25 n. Continuation of table 2 98, 10 S, 0.59 101.25 „,, f 1.6 / 4 98, 10 LBTC 11.6 a 97.72-101.02 20 Table 4 Table 5 0.76; 0.77; 0.77 0.77; 0.78; 0.78 0.76; 0.76; 0.77 150633810 Table 6