Assays of thiotriazoline and pyracetam in complex drugs

FIELD: analytical chemistry.

SUBSTANCE: invention relates to method for quantitative determination of thiotriazoline and pyracetam in complex drugs by high performance chromatography, wherein silicagel with grafted 3-(chlorodimethyl)-propyl-N-dodecylcarbamate having particle size of 5 mum is used as sorbent; and degassed 0.05 M aqueous solution of potassium dihydrophosphate is used as mobile phase. Mobile phase velocity is 1 ml/min, and column temperature is 30°C. Method of present invention makes it possible to determine content of two abovementioned active ingredients simultaneously.

EFFECT: simplified process of sample preparation.

3 ex, 3 tbl

 

The invention relates to the field of analytical chemistry, namely, methods of quantitative determination of piracetam and thiotriazoline medicines when their joint presence in the laboratories of gosinski and CPL chemical and pharmaceutical factories.

Improving the accuracy and selectivity of the methods of quantitative determination, especially in multicomponent dosage forms, is very important in analytical practice and pharmaceutical analysis.

It is known that the substance thiotriazoline quantitatively determined by the method of non-aqueous titration (FS W-45/151-533-99), and in medicinal forms (injectable solutions, tablets, eye drops, ointments) direct spectrophotometric determination in the UV region (FS W-11/151/37-671-00, FS W-9/151-968-00, FS W-11/151-589-99).

Substance piracetam quantitatively determined by the method of kildala (VFS U-711-98), and in dosage forms by spectrophotometry using tutorialinfo (FS W-4-994-00).

In a two-component dosage forms piracetam-thiotriazoline (film-coated tablets "Neotel and injectable solutions) is difficult to quantify as thiotriazoline, and piracetam. So, the definition of piracetam method celdas prevents thiotriazoline, which partially decomposes to form ammonia.

Definition thiotriazoline spectrophotometric method in complex drugs piracetam with thiotriazoline, especially in tablets, interferes with piracetam, which partially absorbs UV light, especially some excipients can absorb UV light in the field of 230-240 nm and this leads to certain errors.

Known methods of analysis thiotriazoline and piracetam dosage forms at their joint presence are labor intensive, require specific approaches when determining the amount of each ingredient.

The proposed method is high performance liquid chromatography (HPLC) to quantify thiotriazoline, piracetam and has a number of advantages, such as ease of sample for analysis, the simultaneous quantification of two active substances, the application of this method for the standardization of the drug on other indicators (e.g., solubility, homogeneity of the dosing and others).

As a result of experimental studies on the determination of active substances in the product by HPLC optimal conditions chromatography was carried out. The study was performed on the chromatograph firms Waters (USA):

- column size of 3.9×150 mm filled with silica gel grafted 3-(chlorodimethylsilyl)propyl-N-dodecylammonium the relationship with the size of particles of 5 microns, for which the conditions of the test "to test the suitability of the chromatographic system;

- mobile phase: 0.05 M solution of potassium dihydrophosphate, degassed in any convenient way;

- rate of mobile phase was 1.0 ml/min;

- detection at a wavelength of 210 nm;

the column temperature was 30°C;

the integration time of the signal is 1 sec;

- scale registration - 0.9 units of optical density.

Assessment of the quantitative content of the investigated substances was carried out according to the method of external standard.

In the conditions of the conducted analysis of model mixtures of the substances under study and pilot plant samples tablets with the purpose of validation of the methodology and its further use in GLP.

The results of the analysis of model mixtures (pill "Neotel", injection solution "Neotel") are shown in tables 1, 2, 3.

The results of the analysis of two pilot scale batches of product are shown in tables 2, 3.

Regarding the chromatograms of the standard solution of the sample (CO) piracetam and thiotriazoline: conducted to test the suitability of the chromatographic system. According to the test checks the suitability of the degree of separation of the peaks of piracetam and thiotriazoline is not less than 2.0 (indicating complete separation of drugs). The efficiency of a chromatographic column, calculated by peak pyracetam, the composition of yet not less than 1300 theoretical plates. The relative standard deviation calculated for the peak area of piracetam is not less than 2.0%. The peak asymmetry factor, calculated by peak piracetam is a maximum of 1.7.

These data indicate the accuracy and reproducibility of the presented methods of quantitative determination of thiotriazoline and pyracetam.

Thus, the developed method for quantitative determination of piracetam and thiotriazoline with high accuracy, reproducibility, selectivity. This technique allows the quantification of piracetam and thiotriazoline in one portion into powders, injectable solutions, tablets, coated tablets.

It has been tested on tablets "Neotel", coated, and injecting the solution "Neotel".

Example 1

Quantitative determination in artificial mixture of piracetam and thiotriazoline in the ratio 4:1.

About 0.25 g of a mixture of piracetam with thiotriazoline, accurately weighed, placed in a volumetric flask of capacity of 100 ml, dissolved in 60-70 ml of purified water, bring purified water to the mark, mix thoroughly.

10 ml of the resulting solution is placed in a volumetric flask capacity of 50 ml, the volume was adjusted with purified water up to the mark, mix thoroughly.

20 μl of the resulting solution chromatographic on highly the positive liquid chromatograph with UV detector, receiving not less than 5 chromatograms under the following conditions:

the column size of 3.9×150 mm filled with silica gel grafted 3-(chlorodimethylsilyl)-propyl-N-dodecylammonium ties with the size of particles of 5 μm, for which the conditions of the test "Primary suitability of the chromatographic system";

- mobile phase: degassed 0.05 M solution of potassium dihydrophosphate;

- the speed of the mobile phase, 1 ml/min;

- detection at a wavelength of 210 nm;

the column temperature was 30°C;

the integration time of the signal is 1 sec.

Simultaneously prepare and chromatographic solution WITH piracetam and thiotriazoline.

Content piracetam grams in the mixture are calculated according to the formula:

where S1- the average value of the peak areas of piracetam investigated mixtures;

S0- the average value of the peak areas of piracetam, solution WITH piracetam and thiotriazoline;

m1the weight of the mixture, in grams;

m0- the weight of the portion of piracetam in the standard sample, in grams;

The p - weight of the mixture of piracetam and thiotriazoline, in grams;

The content of thiotriazoline in grams in the mixture are calculated according to the formula:

where S3- the average value of the peak areas of thiotriazoline investigated mixtures;

S2- the average value of the square is th peaks thiotriazoline, solution WITH piracetam and thiotriazoline;

m1the weight of the mixture, in grams;

m2- the weight of the portion of thiotriazoline in the standard sample, in grams;

The p - weight of the mixture of piracetam and thiotriazoline, in grams.

Notes

1) Preparation of standard solution sample (CO) piracetam and thiotriazoline.

About 0.2 g (accurately weighed) WITH piracetam and 0.05 g (accurately weighed) WITH thiotriazoline placed in a volumetric flask of capacity of 100 ml, dissolved in 60-70 ml of purified water, bring purified water to the mark, carefully stirred.

10 ml of the resulting solution is placed in a volumetric flask of 50 ml, bring purified water to the mark and mix thoroughly.

Solution use freshly prepared.

2) Preparation of the mobile phase.

3.4 g of potassium dihydrophosphate placed in a volumetric flask capacity of 500 ml, dissolved in 350 to 400 ml of purified water, bring purified water to the mark and mix.

Solution use freshly prepared.

3) Check the suitability of the chromatographic system is performed according to the method specified in the State Pharmacopoeia of Ukraine 1 ed., section 2.2.29.

Example 2

Quantitative determination of piracetam and thiotriazoline tablets "Neotel".

About 0.35 g (accurately weighed) of powder pounded 20 tablets "Neotel" (composition: 0.2 g / kg, 0.05 g of teatria the oline, auxiliary substances to 0.356 g) is placed in a volumetric flask of capacity of 100 ml, add 60-70 ml of purified water, stirred for about 10 minutes, bring purified water to the mark, mix, filter through the filter of "blue ribbon", discarding the first 10 to 15 ml of the filtrate.

10 ml of the obtained filtrate is placed in a volumetric flask capacity of 50 ml, the volume was adjusted solution with purified water up to the mark and mix thoroughly.

20 μl of the resulting solution chromatographic on liquid chromatograph with UV detector.

Terms definitions, see example 1.

The content of piracetam in one tablet, in grams, calculated by the formula:

where S1- the average value of the peak areas of piracetam, calculated from the chromatograms powder tablet mass;

S0- the average value of the peak areas of piracetam, calculated from the chromatograms of a solution WITH piracetam and thiotriazoline;

In the average weight of the tablets "Neotel", in grams;

m0- the weight of the portion of piracetam, in grams, taken to cook WITH;

m1- weight tablet mass, in grams.

The content of thiotriazoline, in grams, in one pill calculated by the formula:

where S3- the average value of the peak areas of thiotriazoline calculated with XP is mamogram powder tablet mass;

S2- the average value of the peak areas of thiotriazoline calculated from the chromatograms of a solution WITH piracetam and thiotriazoline;

In the average weight of the tablets "Neotel", in grams;

m2- the weight of the portion of thiotriazoline, in grams, taken to cook WITH;

m1- weight tablet mass, in grams.

Example 3

Quantitative determination of piracetam and thiotriazoline in injectable solution "Neotel (100 g / kg, 25 g thiotriazoline, water for injection to 1000 ml) in 5.0 ml.

2.0 ml of the solution "Neotel" is placed in a volumetric flask of capacity of 100 ml, bringing purified water to the mark, mix thoroughly.

10 ml of the resulting solution is placed in a volumetric flask of 50 ml and bring purified water to the mark.

20 μl of the resulting solution chromatographic, as shown in example 1.

The content of pyracetam, in grams, in 1 ml of the solution calculated by the formula:

where S1- the average value of the peak areas of piracetam, calculated from the chromatograms of the investigated solution;

S0- the average value of the peak areas of paracetamo calculated from the chromatograms of a solution WITH piracetam and thiotriazoline;

m0- the weight of the portion of piracetam, in grams, in;

m1- the number of ml of injection solution "Neotel"taken for analysis.

The content of thiotriazoline, in grams, in 1 ml of the solution calculated by the formula:

where S3- the average value of the peak areas of thiotriazoline calculated from the chromatograms of the investigated solution;

S2- the average value of the peak areas of thiotriazoline calculated from the chromatograms of a solution WITH piracetam and thiotriazoline;

m2- the weight of the portion of thiotriazoline, in grams, in;

m1- the number of ml of injection solution "Neotel"taken for analysis.

The method for quantitative determination of piracetam and thiotriazoline medicines when their joint presence using high-performance liquid chromatography, characterized in that the sorbent using silica gel with grafted 3-(chlorodimethylsilyl)propyl-N-dodecylamine ties with the size of particles of 5 μm, and as the mobile phase is degassed 0.05 M aqueous solution of potassium dihydrophosphate with the velocity of the mobile phase, 1 ml/min at a column temperature of 30°C.



 

Same patents:

FIELD: medicine, medicinal toxicology, microbiology, biology.

SUBSTANCE: invention relates to a method for testing different immune preparations, for example, immunoglobulins. Method involves carrying out the combined culturing test-strain of microorganism with the corresponding immune preparation under standard conditions of the human embryo monolayer of cultured cells. Results are estimated by degree of the adhesion decrease value of test-strain of microorganism as compared with control value. Invention provides elevating rate in evaluation of an anti-infectious activity of immune preparations based on approaching conditions of evaluation to macroorganism conditions.

EFFECT: improved method of evaluation.

2 tbl, 2 ex

FIELD: medicine.

SUBSTANCE: method involves scanning pulse with glass plate placed on pulse measurement point. The glass plate bears biological test system containing composition of 0.1% aqueous amino acid solutions like tryptophan, aspartic acid, alanine, treonine, valine, serine, glycine and tyrosine taken in equal proportions, 0.5% aqueous solution of dopamine, 0.5% aqueous solution of histamine, 12% aqueous solution of magnesium sulfate taken in 3:3:13 proportion. The plate is hold on pulse for 1-2 min before and 10-15 min after giving the pharma- or parapharmaceutic under study to a patient. Then, the plate is dried at T=+18-20°C during 2-3 min and another glass plate is covered with biological test system surrounded with wall of the pharma- or parapharmaceutic under study arranged along periphery and dried at T=+18-20°C during 2-3 min. The biological test system structures formed on the plates are compared in polarized light with quartz compensator. Structural similarity being detected, identification of pharma- or parapharmaceutic introduced into human organism is to be recorded.

EFFECT: enhanced effectiveness in identifying biologically active substances introduced into human organism.

26 dwg

FIELD: analytical methods in medicine.

SUBSTANCE: concentration of miramistin (C26H47N2O) in an aqueous medium is found from spectrophotometrically measured optical density of solution. Spectrophotometric measurement is performed in the region of maximum UV absorption of solution, namely within 261-263 nm wavelength range.

EFFECT: simplified analytical procedure at rather high accuracy level.

2 tbl

FIELD: medicine, clinical pharmacology.

SUBSTANCE: invention relates to a method for identification of antidepressant possessing an anti-itching effect by using the computer program for measurement of models of chemical structures. Method involves visual analysis of all stable conformers of antidepressant molecule and antidepressant possessing anti-itching effect is identified in detection at least one stable conformer comprising structure of two inter-centered aromatic rings wherein their planes are able to orient at angle 120° with respect to one another. Also, invention relates to using antidepressant identified by above described method in treatment of itching. Invention provides identifying anti-itching effect of antidepressants.

EFFECT: improved method for identification.

2 cl, 7 ex

FIELD: gene engineering.

SUBSTANCE: the present innovation deals with transferring a mutant gene due to homologous recombination into animal embryo. The animal obtained is characterized by the capacity to express mutant protein of presenylin-1 and induction of beta-myeloid protein production that leads to the development of progressing nervous disease in hippocampus or peripheral department of cerebral cortex, It is, also, suggested to apply several plasmids carrying a mutated gene. It is, also, described the way to obtain primary cell culture or subcultivated cell out of obtained mutated animals. Moreover, several methods are, also, suggested for testing the substances for usefulness in therapeutic and/or prophylactic procedures at treating Alzheimer's disease. They deal with introducing a tested substance for mutated animal to evaluate the data obtained. The obtained mutated animals could be applied as model animals while studying Alzheimer's disease nature.

EFFECT: higher efficiency.

25 cl, 8 dwg, 10 ex

FIELD: medicine.

SUBSTANCE: method involves determining quantitative and qualitative composition of short chain fatty acids of C2-C4 fraction in feces and peripheral blood serum to evaluate fatty acids metabolism at various levels (hepatic, vesicular and intestinal).

EFFECT: high accuracy in measuring metabolism characteristics at various levels; accelerated process.

1 tbl

FIELD: medicine, microbiology.

SUBSTANCE: invention relates to a method for assay of pathogenicity of microorganism Staphylococcus epidermidis. Method involves incubation of experimental samples isolated from donors with lactofferin taken in the concentration 320-580 ng/ml followed by counting amount of revived microorganisms as compared with control value. Advantage of invention involves enhancing sensitivity of method.

EFFECT: improved assay method.

1 tbl, 3 ex

FIELD: medicine, in particular urology.

SUBSTANCE: method relates to method for determination of pathogenic activity of microorganism staphylococcus epidermidis isolated from sperm. Microorganism samples isolated from donors are incubated with spermine or spermidine in concentration of 0.02-0.06 mg/ml followed by determination of survived microorganism amount by comparison of sample and standard optical density. Increased microorganism amount in sample in contrast with standard denotes the pathogenic activity of analyzed strain.

EFFECT: method with improved selectivity and accuracy.

3 ex, 2 tbl

FIELD: microbiology, pharmaceutical agents.

SUBSTANCE: invention relates to method for determination of genome response of specific cells to vegetable extract action. Method for drug screening includes 1) treatment of specific cells with vegetable extract; 2) protein or RNA isolation from said treated cells; 3) identification of isolated protein or RNA; 4) determination of compound(s) in said vegetable extract; 5) treatment of said cells with determined compound(s); 6) protein or RNA isolation from said treated cells; and 7) determination of compounds providing expression or suppression of said protein or RNA which have another concentration than in untreated said specific cells.

EFFECT: identification of individual compound(s) for screening of new pharmaceutical agents or new pharmaceutical application of existing drugs.

14 cl

The invention relates to biology and medicine and relates to a method for the identification of new anti-inflammatory drugs, molecules that contain common code fragment: carbonyl - phenyl radical, a secondary or tertiary amino group, for example, four rows derivatives of Anthranilic acid, namely, the first N-substituted Anthranilic acid, the second arylamide and hydrazides N alkenylphenol acids, third - arylamine N-acetyl-N-alkynylaryl acids, fourth - allylamine N-acylanthranilic acids, the representatives of which in the experiment on animal model carragenine edema determine the anti-inflammatory effect (EDTexp

FIELD: analytical methods.

SUBSTANCE: to determine methyl alcohol in water, sample to be assayed is preliminarily subjected to distillation with sulfuric acid added in amount required to provide its concentration in mixture to be distilled c(1/2 H2SO4) = 0.002 M, while strippings constitute 6-7% of the volume of sample. Stripped liquid is thrice rinsed with hexane or Nefras at 1:1 hexane (Nefras)-to-strippings ratio. Rinsed material is then introduced into packed column filled with diatomite modified with 1,2,3-tris(β-cyanoethoxy)propane having deposited fixed phase thereon, which phase is prepared by way of consecutively keeping glycerol each time for 4 h at ambient temperature, 100°C, 130°C, 160°C, and 200°C, and then for 8 h at 230°C and for 40 h at 200°C under nitrogen bubbling conditions. Calculation of methanol content is performed taking into consideration calibrating coefficient.

EFFECT: enabled determination of small concentrations of methyl alcohol in water with sufficient selectivity and reliability.

2 cl, 2 tbl, 6 ex

Gas analyzer // 2267123

FIELD: investigating or analyzing materials.

SUBSTANCE: gas analyzer comprises chromatographic columns, detectors, unit for preparing air mounted inside the thermostat, unit for control and processing signals, member for sampling, switches of gas flows, pump for pumping gas mixture, and separating passages connected in parallel and provided with the check valve interposed between them. Each of the separating passages is made of absorbing and separating chromatographic columns connected in series, and the pump is connected to the input of the gas line through the electric valve. The gas analyzer can be made of two separating passages and low pressure chromatographic columns.

EFFECT: enhanced quality of analyzing.

2 cl, 1 dwg, 1 ex

FIELD: physics.

SUBSTANCE: in the method, hard carrier with system of narrow pores and channels is kept under temperature below height of potential barriers for movement of at least one type of separated molecules.

EFFECT: higher efficiency.

4 dwg

FIELD: oil and gas production.

SUBSTANCE: aim of invention is estimating expectations for oil and gas of oil-source rock areas. For that aim, sampled rock is treated to isolate organic substance soluble in organic solvents, after which organic substance is chromatographed to detect 4-methyldibenzothiophene and 1-methyldibenzothiophene. When ratio of 4- to 1-isomer exceeds 0.9 rock is regarded as ripened.

EFFECT: increased determination reliability and rapidity.

2 tbl

FIELD: chemical industry.

SUBSTANCE: during process of taking sample from technological pipe-line, absorption of water vapors and nitrogen oxides (II) and (IV) are conducted simultaneously. For the purpose the chemical agents are used which don't absorb nitrogen oxide and don't react with it. Chromatographic measurement of volume fraction of nitrogen oxide (I) is carried out by means of industrial chromatograph having heat-conductance detector by using column of thickness of 5 m and diameter of 3 mm. The column is filled with polysorbent; temperature of column's thermostat is 20-30 C and temperature of evaporator is 100C. Hydrogen is used as a gas-carrier. Concentrations of nitrogen oxide, measured by the method, belong to range of 0, 05-0, 50% of volume fraction. Method excludes aggressive affect of corrosion-active components on sensitive parts of chromatograph. Method can be used under industrial conditions for revealing factors influencing process of forming of nitrogen oxide at the stage of catalytic oxidation of ammonia and searching for optimal conditions for minimizing effluent of ammonia into atmosphere.

EFFECT: high reproduction; simplification; improved efficiency of operation.

3 ex

FIELD: analytical chemistry, ecology, in particular controlling of environmental air.

SUBSTANCE: claimed method includes aspiration if air sample through chemosorbtive medium, elution of formed dimethylamine salt, eluate closure with alkali, and gas chromatography analysis of gas phase with flame-ionization detection. Dimethylamine salt elution from adsorbent is carried out with 1 cm3 of distillated water; closured with alkali eluate is held in thermostat for 5 min; and as filling in separating chromatography column chromosorb 103, containing 5 % of PEG-20000 and treated with 20 % hexamethyldisilazane solution is used.

EFFECT: method for dimethylamine detection with improved sensibility and accuracy.

FIELD: chemical engineering; medical engineering.

SUBSTANCE: method involves plotting two chromatograms one of which is based on radioactivity (No 1) and the other one on ultraviolet absorption (No 2) or on radioactivity (No 1) and on fluorescence (No 2) and chromatogram specific relative to ultraviolet absorption (No 3) or relative to fluorescence (No 3). Material quality is estimated to be the more high the more close studied labeled compound peak shape is to trapezoid shape on the third chromatogram.

EFFECT: high accuracy of the method.

8 dwg

The invention relates to the field of analysis of the safety and hygiene of food products and food raw materials, namely, to determine the toxicity of 1-nitrosoamines in food products by the method of inverse gas chromatography

,'illogicality on individual index holding" target="_blank">

The invention relates to the field of chemical analysis and physical properties of substances, particularly to the analysis of non-biological materials by physical and chemical methods

FIELD: organic chemistry, possible use when determining total organic pollution of surface, underground, drinking and industrial waters, and also for determining total amount of volatile compounds in these waters.

SUBSTANCE: in accordance to method for determining total organic pollution of water, a sample of water with organic pollution is taken, subjected to effect of ultraviolet radiation, in process of this effect, light absorption coefficient is measured, content of soluble iron is determined by means of chemical analysis and, if iron content does not exceed 0,15 mg/dm3, content of common organic carbon is calculated using formula C=k/a [%dm3/mg], where C - content of common organic carbon, mg/dm3; k - light absorption coefficient, %; a - experimentally calculated proportionality coefficient, characterizing connection between light absorption coefficient and content of common organic carbon at volumetric concentration of sample, having light absorption coefficient above 25% and content of soluble iron not above 0,15 mg/dm3.

EFFECT: simplification of realization, high objectivity of evaluation, high precision of measurements.

3 tbl, 1 dwg

Up!