RU1826049C - Method for performing quantitative analysis of multicomponent pharmaceuticals for dimedrol - Google Patents

Abstract

Usage: in analytical chemistry SUMMARY OF THE INVENTION: A sample of an aqueous solution of diphenhydramine is treated with an O, 5% aqueous solution of chloranilic acid, followed by extraction of the resulting colored compound with chloroform, photometry and quantification. A table. "

Description

The invention relates to the analysis of organic chemical compounds, in particular to methods for the quantitative determination of arylalkylamines (diphenhydramine), and can be used in quality control of products manufactured by pharmaceutical manufactures and manufactured in pharmacies. Diphenhydramine is one of the main representatives of the group of antihistamines, along with this sedative anticholinergic and anti-inflammatory effect. It is widely used in complex drug mixtures.

The aim of the invention is to simplify the method, reduce the determination time and increase the accuracy of the analysis.

The goal is to reduce analysis time, improving accuracy is achieved by the fact that in the known method for the determination of diphenhydramine, which consists in processing

the analyte sample solution with a color reagent and photometry; the sample is treated with a color reagent with a 0.5% aqueous solution of chloranilic acid and subsequent extraction of the colored product with chloroform, without heating for 20-30 minutes.

The advantage of this method is its simplification by eliminating the first stage of the reaction with quinones, namely heating at 75 ° С for 20 min in a nonaqueous medium (dioxane), halving the analysis time by 2 times, and increasing selectivity by eliminating the effect on the optical density of the colored product of impurities and intermediate reaction products due to extraction with chloroform.

Additional studies showed that the maximum light absorption of the reaction product is at

00 Yu O

g

45

a wavelength of 540 nm. The reaction proceeds in a molar ratio of 1: 1. Color stability is maintained for 4-5 hours,

PRI me R 1. The definition of diphenhydramine in a substance.

Procedure: about 0.15 g (accurately weighed) of diphenhydramine powder meeting the requirements of GPC is placed in a 100 ml volumetric flask, dissolved in water and the solution is brought to the mark with water, 0.5 ml of the resulting solution is transferred into 25 ml separatory funnel. 10 ml of chloroform and 5 ml of a 0.5% aqueous solution of chloranilic acid are preliminarily added. Extract 10 ml of chloroform in two portions into a 25 ml volumetric flask and adjust the solution to the mark with chloroform. The optical density of the colored solution is measured using an SF-46 spectrophotometer or a KFK-2 MP photoelectric calorimeter at a wavelength of 540 nm, in a cuvette with a working layer thickness of 10 mm. Chloroform extraction of blind experiment is used as a comparison solution.

In parallel, a standard solution of diphenhydramine containing 0.0075 g of the drug in 1 ml is determined.

Further calculations to determine the quantitative content of diphenhydramine (in grams) were carried out according to the following formula

V h

Px 0.00375 Do -0.15 -0.5

where 0.00375 is the content of diphenhydramine in 0.5 ml of a standard solution;

0.15 g - the exact weight of the drug;

0.5 g is the number of ml of preparation taken for determination.

The data of 10 experiments on the determination of dimedrol in a substance are presented in Table 1.

PRI me R 2. Quantitative determination of diphenhydramine in a cardiological mixture of Valeodicramen.

Composition: Diphenhydramine 0.3

N-ki Bo Ryshnik 10ml

N-valerian10ml

Peppers 10 ml

Strawberry 10 ml

10 ml of chloroform and 5 ml of a 0.5% aqueous solution of chloranilic acid are measured in a 25 ml separatory funnel. Shake the contents. Then, 0.5 ml of the preparation is introduced into the separatory funnel with the reaction mixture. Extract two portions of chloroform (10 ml each) into a 25 ml volumetric flask and adjust to the mark with chloroform. Optical

the density of the resulting colored solution on an SF-46 spectrophotometer or FEK KFK-2MP spectrophotometer at a wavelength of 540 nm, in a cuvette with a working layer thickness of 10 mm.

Chloroform blind blind extract was used as a comparison solution. Calculation of the quantitative content of diphenhydramine is carried out according to the formula I in a known manner, in parallel the density of a standard diphenhydramine solution is measured.

The results of the quantification of diphenhydramine in a cardiological mixture are presented in Table 2.

Example 3. Quantitative determination of diphenhydramine in liniment. Composition: Diphenhydramine 1.0

Zinc Oxide 10.0

Sunflower oil Up to 100.0 Procedure: An exact weighed portion of liniment containing 0.02 g of diphenhydramine is placed in a flask, a small amount of water is added, chloroform is shaken until the base of the preparation is dissolved, filtered. 10 ml of chloroform and 5 ml of a 0.5% solution of chloranilic acid are measured in a 25 ml separatory funnel. Then, 0.5 ml of the preparation is added to the separatory funnel with the reaction mixture. It is extracted with 2 portions of 10 ml chloroform into a 25 ml volumetric flask and adjusted to the mark with chloroform. The optical density of the colored solution was measured using an SF-46 spectrophotometer or a KFK-2MP photoelectrocolorimeter at a wavelength of 540 nm, in a cuvette with a working layer thickness of 10 mm. Chloroform extraction of blind experiment is used as a comparison solution.

At the same time, the optical density of a standard solution of diphenhydramine containing 0.0055 g of the preparation in 1 ml is determined. Further calculations on the quantitative content of diphenhydramine are carried out according to the formula I.

PRI me R 4. Determination of diphenhydramine in ointments used in pediatrics. Composition: Diphenhydramine 0.25

Menthol 0.4

Streptocide 3.0

Zinc Ointment 40.0

Methodology About 0.25 g (accurately weighed) of the ointment is shaken with 5 ml of ether and 5 ml of water until the base of the preparation is dissolved and the mixture is filtered. 10 ml of chloroform and 5 ml of a 0.5% aqueous solution of chloranilic acid are measured into a 25 ml separatory funnel. Then, 0.5 ml of the obtained filtrate is introduced into the separatory funnel with the reaction mixture. It is extracted with 2 portions of 10 ml chloroform into a 25 ml volumetric flask and adjusted to the mark with chloroform.

The optical density of the resulting colored solution was measured at a wavelength of 540 nm, in a cuvette with a working layer thickness of 10 mm. Chloroform extraction of blind experiment is used as a comparison solution. Then, the content of diphenhydramine is calculated by the formula I. - The results of the quantitative determination of diphenhydramine in ointment are presented in Table 4.

In conclusion, it should be noted that the proposed method for the determination of diphenhydramine is characterized by the replacement of the quinone reagent in a nonaqueous solvent (chloranil) with an aqueous solution of quinone (a 0.5% solution of chloranilic acid), which eliminates the need for prolonged heating of the reaction mixture in a nonaqueous mixture (wild - dignity), reduces time from 1 hour to

30 min, increases the selectivity and versatility of the method,

The photoextraction method allows the determination of diphenhydramine in various dosage forms (cardiological mixture, ointments, liniment used in pediatrics).

Claims (1)

SUMMARY OF THE INVENTION A method for the quantitative determination of diphenhydramine in multicomponent pharmaceutical preparations, which consists in processing a sample with a color reagent in an organic solvent medium followed by photometric measurement of the obtained colored solution, characterized in that, in order to simplify, shorten the determination time and increase accuracy, 0 is used as a color reagent. 5% aqueous solution of chloraniloyl acid, the resulting colored compound is extracted with chloroform and subjected to photometry extract. Table 1 Table 2 Table3 Table 4