Method of determining glycine in an aqueous solution

FIELD: analytical methods.

SUBSTANCE: method of determining glycine when developing continuous protein fermentation processes consisting in preparing aqueous solution of glycine followed by extraction and further analysis of organic phase is characterized by that 20-35% by weight of lithium sulfate as salting-out agent is added to aqueous solution of glycine (pH˜5) and then solution is extracted with ternary mixture of hydrophilic solvents: 65-65.5% isopropyl alcohol, 20-20.5% acetone, and 14-15% ethyl acetate at volume ratio of extractant mixture to aqueous salt solution 1:10. Nonaqueous concentrate is further analyzed using potentiometric titration technique.

EFFECT: increased degree of glycine recovery to 98-99% and avoided use of dangerous reagents in organic phase analysis.

1 tbl, 11 ex

 

The invention relates to analytical chemistry of organic compounds and can be used in process development, continuous fermentation of proteins.

The closest in technical essence and the achieved effect is the extraction method determination of amino acids in aqueous solutions with the use of dinonyl naphthalene sulfonic acid (Svemirska, Env, I. C. Pletnev. Extraction of amino acids with dinonylnaphthalenesulfonic acid in the presence of DICYCLOHEXYL-18-crown-6 // News. Mosk. Univ. Series 2. Chemistry. 2000. V.41. No. 3. S-188.), comprising preparing an aqueous solution of glycine, extraction and analysis of the aqueous phase.

The disadvantages of this method are the low degree of extraction of glycine (40%), the use of toxic compounds - ninhydrin - by Spectro-photometric analysis of an aqueous solution of glycine.

An object of the invention is to increase the degree of extraction of glycine to 98-99%, the analysis of the organic phase with the safe use of chemicals.

The technical problem is achieved by the method of determination of glycine in aqueous solution, comprising preparing an aqueous solution of glycine, extraction and analysis of the organic phase, it is new that to aqueous solution of glycine (pH≈5) add 20-25 wt.% vicariates - lithium sulfate, extracted with three-component mixture of hydro is strong solvents, consisting of 65-65 .5 wt.% isopropyl alcohol, 20-20 .5 wt.% acetone and 14-15 wt.% ethyl acetate at a volume ratio mixture of extractants and aqueous-salt solution 1:10, non-aqueous concentrate analyzed by potentiometric titration.

The technical result consists in increasing the degree of extraction of glycine in aqueous solution up to 98-99%, the analysis of the concentrate with the safe use of chemicals.

The proposed method for the determination of glycine in aqueous solution is carried out by the following method.

To 20 ml of an aqueous solution of glycine with pH≈5 (initial concentration of glycine 0.05-0.1 mg/ml) add 20-25 wt.% vicariates sulfate lithium, 2 ml of a mixture of hydrophilic solvents (65-65 .5 wt.% isopropyl alcohol, 20-20 .5 wt.% acetone and 14-15 wt.% ethyl acetate and extracted on vibromaster to establish the interfacial equilibrium (5 min). After stratification (1-2 min), the organic phase is quantitatively separated from the aqueous phase and analyzed by potentiometric titration in acid-base mechanism. Titrant - 0.01 mol/l KOH solution in anhydrous ethyl alcohol. The indicator electrode is chemically neutral glass electrode, characterized by the maximum change in potential near the point of stereometrical. The reference electrode is chloresteral filled with a saturated solution is lorida potassium ethyl alcohol to prevent the ingress of water from the electrode into the organic phase. Electromotive force is measured on the high-resistance potentiometer, build a differential potentiometric titration curve based changes EMF from the volume of titrant.

On the differential potentiometric titration curve of glycine has a maximum corresponding to the content of the acid in the extract. The organic phase is transferred 98-99% glycine from its original content in the analyzed solution.

The implementation of the method is illustrated by the following examples.

Example 1

To 20 ml of the analyzed aqueous solution of glycine (pH≈5) add 2 ml of a solvent mixture containing 65 wt.% isopropyl alcohol, 20 wt.% acetone and 15 wt.% ethyl acetate. Extracted on vibromaster 5 minutes Extraction with a mixture of a hydrophilic solvent in the absence of vicariates does not lead to the formation of the organic phase, the method impracticable.

Example 2

To analyze the solution of glycine (pH≈5) add crystal lithium sulfate to obtain a solution with a salt content of 20 wt.%. To 20 ml of water-salt solution of glycine add 3 ml of solvent mixture containing 65 wt.% isopropyl alcohol, 20 wt.% acetone and 15 wt.% ethyl acetate. Extracted on vibromaster 5 min, the extract is separated, not grasping the aqueous layer, quantitatively transferred into a cell for potentiometric titration and titrated 001 mol/l KOH solution in anhydrous ethyl alcohol. The indicator electrode is chemically neutral glass electrode, characterized by the maximum change in potential near the point of stereometrical. The reference electrode is chloresteral filled with a saturated solution of potassium chloride in ethyl alcohol to prevent the ingress of water from the electrode into the organic phase. Electromotive force is measured on the high-resistance potentiometer, build a differential potentiometric titration curve based changes EMF from the volume of titrant.

On the differential potentiometric titration curve of glycine has a maximum corresponding to the content of the acid in the extract. The recovery (R%) of glycine are calculated according to the formula

R=D·100/D+r

where D is the distribution coefficient of glycine between the mixture of solvent and water-salt solution, r is the ratio of the equilibrium volumes of aqueous and organic phases.

The organic phase transitions that 98.9% of glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) extract of glycine, the method is executed.

Example 3

The analysis performed as in example 2, but to aqueous solution of glycine type crystalline lithium sulfate in the amount of 25 wt.%. The organic phase is transferred 98.6% glycine from the original content in the analyzed solution. Achieved a CR is chicosci full (98-99 wt.%-Noah) removing glycine, the method is executed.

Example 4

The analysis performed as in example 2, but to aqueous solution of glycine type crystalline lithium sulfate in the amount of 30 wt.%. After extraction are crystals vicariates, the method impracticable.

Example 5

The analysis performed as in example 2, but by water and salt to a solution of glycine type three-component mixture of a hydrophilic solvent containing 45 wt.% isopropyl alcohol, 10 wt.% acetone and 45 wt.% ethyl acetate. The organic phase is transferred 35.6% glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved, the method impracticable.

Example 6

The analysis performed as in example 2, but by water and salt to a solution of glycine type three-component mixture of a hydrophilic solvent containing 70 wt.% isopropyl alcohol, 25 wt.% acetone and 5 wt.% ethyl acetate. The organic phase is transferred 80.3% of glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved, the method impracticable.

Example 7

The analysis performed as in example 2, but at the pH of the aqueous salt solution of glycine equal to 3. The organic phase is transferred 65.6% of glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved, the procedure impossible.

Example 8

The analysis performed as in example 2, but at the pH of the aqueous salt solution of glycine equal to 4. The organic phase is transferred 70.1% of glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved, the method impracticable.

Example 9

The analysis performed as in example 2, but at the pH of the aqueous salt solution of glycine equal to 6. The organic phase is transferred 39.7% of glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved, the method impracticable.

Example 10

The analysis performed as in example 2, but at the pH of the aqueous salt solution of glycine equal to 7. The organic phase is transferred 49,6% glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved, the method impracticable.

Example 11

The analysis performed as in example 2, but to aqueous solution of glycine type crystalline lithium sulfate in the amount of 15 wt.%. The organic phase jumps 54% glycine from the original content in the analyzed solution. Almost complete (98-99 wt.%-Noah) removing glycine is not achieved. The method impracticable.

The table shows the comparative characteristics of examples of the determination of glycine in aqueous solution by the present method.

As can be seen from the ablity, the positive effect of the proposed method is achieved when the content of vicariates 20-25 wt.%, the application of three-component mixtures of hydrophilic solvents consisting of 65-65 .5 wt.% isopropyl alcohol, 20-20 .5 wt.% acetone and 14-15 wt.% ethyl acetate and the volume ratio mixture of extractants and aqueous-salt solution 1:10.

Comparative characteristic examples of the determination of glycine in aqueous solution by the present method
Number exampleThe content of vicariates, wt.%the pH of the analyzed solutionThe composition of the extractant, wt.%The degree of extraction of glycine,%
isopropyl alcoholacetonethe ethyl acetate
1-5652015-
2205652015the 98.9
325565201598,6
4305652015 -
520545104535,6
62057025580,3
720365201565,6
820465201579,1
920665201539,7
1020765201549,6
1115565201554,0

The method of determination of glycine in aqueous solution, comprising preparing an aqueous solution of glycine, extraction, and analysis of the organic phase, wherein the aqueous solution of glycine (pH≈5) pre-add visivel - sulphate to lithium concentration in the solution 20-25 wt.%, the extraction was carried out three-component mixture of hydrophilic solvents consisting of 65-65 .5 wt.% isopropyl alcohol, 20-20 .5 wt.% acetone and 14-15 wt.% ethyl acetate at a volume ratio mixture of extractants and the one-saline 1:10.



 

Same patents:

FIELD: organic chemistry, chemical technology, medicine.

SUBSTANCE: invention relates to a method for preparing the synthetic 5-aminolevulinic (5-amino-4-oxopentanoic) acid hydrochloride (5-ALA) representing an endogenous substance (metabolite). Method for preparing 5-ALA involves electrochemical reduction of 5-nitrolevulinic acid methyl ester in acid aqueous medium on graphite cathode at temperature 60-75°C and the current density value 2-10 A/dm2. 5-ALA can be used in medicine for photodiagnosis and photodynamic therapy of malignant tumors of different localization and for treatment of diseases of non-tumor nature also. Invention provides simplifying technology of synthesis of 5-ALA, improved economy indices and provides ecological safety of the process.

EFFECT: improved preparing method.

4 ex

The invention relates to an improved method for producing a water-soluble amino acid derivatives of fullerene that can be used in pharmacology and Microbiology
The invention relates to an improved method for producing a water-soluble salts of amino acid derivatives of fullerene that can be used in pharmacology, Microbiology and medicine
The invention relates to the production of 4-aminobutyric acid (-aminobutyric acid), used for the manufacture of neurotropic drug aminalona, and also as an intermediate product for the synthesis of a number of other pharmaceutical preparations, for example, to retrieve picamilon

The invention relates to the production of new labeled analogue of physiologically active compounds O-(4-hydroxy-3,5-diiodophenyl)-3',5'-diiodo-L-tyrosine ("t") the compounds of formula 1, which can be used in organic chemistry, biology and medicine

The invention relates to new 6-dimethylaminomethyl-1-phenylcyclohexane compounds of General formula 1 in the form of bases or of their physiologically acceptable salts exhibiting analgesic activity and intended for the production of pharmaceutical compositions, and to methods for their preparation

The invention relates to a process for the preparation of organic compounds labeled with stable isotopes, namely to obtain deuterated glycine, which can be used in physico-chemical and spectral studies

The invention relates to a method for producing synthetic hydrochloride of 5-aminolevulinic (5-amino-4 - oxopentanoate) acid formula HCLH2NCH2COCH2CH2COOH

FIELD: analytical methods.

SUBSTANCE: method of determining glycine when developing continuous protein fermentation processes consisting in preparing aqueous solution of glycine followed by extraction and further analysis of organic phase is characterized by that 20-35% by weight of lithium sulfate as salting-out agent is added to aqueous solution of glycine (pH˜5) and then solution is extracted with ternary mixture of hydrophilic solvents: 65-65.5% isopropyl alcohol, 20-20.5% acetone, and 14-15% ethyl acetate at volume ratio of extractant mixture to aqueous salt solution 1:10. Nonaqueous concentrate is further analyzed using potentiometric titration technique.

EFFECT: increased degree of glycine recovery to 98-99% and avoided use of dangerous reagents in organic phase analysis.

1 tbl, 11 ex

FIELD: organic chemistry, biochemistry, chemical technology.

SUBSTANCE: invention relates to a method for purification of synthetic 5-aminolevulinic (5-amino-4-oxopentaenic) acid hydrochloride (5-ALA) representing endogenous substance and biological precursor of porphyrines in living organism and plants. Preliminary purification of 5-ALA hydrochloride is carried out by electrodialysis of 5-ALA solutions with the concentration 140-300 g/l in current density 0.5-2.0 A/dm2 and at temperature 20-30°C. Proposed method of purification of 5-ALA hydrochloride provides isolating expensive preparation from filtrates and to enhance the content of basic substance in technical 5-ALA hydrolyzate prepared by catalytic and electrochemical methods with the parent content of basic substance 87.0%, not above, that results to enhancing yield of final 5-ALA hydrochloride. Purified substance can be used in research and industrial practice.

EFFECT: improved purifying method.

8 ex

FIELD: chemistry.

SUBSTANCE: anhydride is a physiologically active substance and can be used, for example, in chemotherapy as a low-toxic agent for inhibiting growth of carcinoma 755 (breast cancer). The object of the present invention is synthesis of a novel mixed anhydride based on dichloroacetic and aminoacetic acid which, for instance, enables to inhibit growth of carcinoma 755 (breast cancer) in monotherapy. The given task is solved through synthesis of a novel mixed anhydride based on dichloroacetic acid and aminoacetic acid of formula 1, which can be used in medical practice as an anti-tumour agent which enables, for example, to inhibit growth of carcinoma 755. The other objective of the invention is designing a method of producing the mixed anhydride based on dichloroacetic acid and aminoacetic acid. This task is solved using a method which involves successive reaction of aminoacetic acid with an alkali metal hydroxide in an aqueous medium followed by treatment of the reaction mass with dichloroacetyl chloride in a chloroalkane solution, acidation of the reaction medium with aqueous hydrochloric acid solution and extraction of the end product using existing techniques. The disclosed compound can be used in medical practice as an anti-tumour compound.

EFFECT: use of said compound in oncological practice inhibits growth of carcinoma.

2 cl, 1 ex

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to a method for preparing a solid form of the compound gadobenate dimeglumine of formula (I) used as a contrast agent for diagnostic visualisation, particularly in magnetic resonant tomography. The presented method involves spray drying of a liquid composition of the above compound. Preferentially, the liquid composition represents an aqueous solution. The invention also refers to a solid powder form of gadobenate dimeglumine prepared by the method described above, a pharmaceutical kit containing this form, and a method for preparing a solid form of 4-carboxy-5,8,11-tris(carboxymethyl)-1-phenyl-2-oxa-5,8,11-triazatridecane-13 acid.

EFFECT: method enables preparing the high-yield and reproducible solid form of gadobenate dimeglumine, which possesses good flowability and dissolution rate.

15 cl, 3 ex

FIELD: organic chemistry, chemical technology, medicine.

SUBSTANCE: invention relates to a method for preparing the synthetic 5-aminolevulinic (5-amino-4-oxopentanoic) acid hydrochloride (5-ALA) representing an endogenous substance (metabolite). Method for preparing 5-ALA involves electrochemical reduction of 5-nitrolevulinic acid methyl ester in acid aqueous medium on graphite cathode at temperature 60-75°C and the current density value 2-10 A/dm2. 5-ALA can be used in medicine for photodiagnosis and photodynamic therapy of malignant tumors of different localization and for treatment of diseases of non-tumor nature also. Invention provides simplifying technology of synthesis of 5-ALA, improved economy indices and provides ecological safety of the process.

EFFECT: improved preparing method.

4 ex

FIELD: analytical methods.

SUBSTANCE: method of determining glycine when developing continuous protein fermentation processes consisting in preparing aqueous solution of glycine followed by extraction and further analysis of organic phase is characterized by that 20-35% by weight of lithium sulfate as salting-out agent is added to aqueous solution of glycine (pH˜5) and then solution is extracted with ternary mixture of hydrophilic solvents: 65-65.5% isopropyl alcohol, 20-20.5% acetone, and 14-15% ethyl acetate at volume ratio of extractant mixture to aqueous salt solution 1:10. Nonaqueous concentrate is further analyzed using potentiometric titration technique.

EFFECT: increased degree of glycine recovery to 98-99% and avoided use of dangerous reagents in organic phase analysis.

1 tbl, 11 ex

FIELD: chemistry, medicine.

SUBSTANCE: claimed invention relates to main fatty acid ethers of general formula R1-O-CO-A or their pharmaceutically acceptable salts, where R1 represents C10-C24alkenyl, and A represents residue, containing at least one acyclic or cyclic aminogroup and/or at least one heteroaromatic ring, which contains tertiary or quaternary nitrogen atom, and to their application as anti-inflammation or immunomodulatory medications in particular for treatment of immune-mediated inflammation, as well as adjuvants for antigens, participating in cell and humoral response.

EFFECT: invention ensures enhancing composition and treatment method efficiency.

180 cl, 22 ex, 4 tbl, 10 dwg

FIELD: chemistry.

SUBSTANCE: novel stabilised antiperspirant salts of aluminium/zirconium/glycine contain stabilizing additive, representing betaine of formula I in amount sufficient to ensure (a) total ratio (betaine+glycine)/Zr within interval 0.1-3.0:1, (b) ratio of betaine to glycine 0.001:1; and (c) enough betaine to ensure 0.1% of ratio betaine+glycine at expense of betaine, and to method of their production.

EFFECT: obtaining improved antiperspirant or deodorant product.

9 cl, 3 ex, 10 tbl

FIELD: chemistry.

SUBSTANCE: antiperspirant salt composition including aluminium and/or zirconium salt with betaine with mol ratio of metal to chloride within 0.3-2.5:1 range, mol ratio of betaine to aluminium within 0.05-1.0:1 range and/or mol ratio of betaine to zirconium within 0.2-3.0:1 range, where betaine is applied in its regular form described in the formula I , or in the form of derivated betaine hydrochloride described in the formula IA .

EFFECT: obtaining salt composition with aluminium and/or zirconium salt and betaine for improvement of cosmetic goods quality.

12 cl, 39 ex, 5 tbl

FIELD: chemistry.

SUBSTANCE: invention refers to pharmaceutical chemistry, namely to new biologically active substances (BAS) and to their properties, namely to kreatine derivatives of general formula: NH=C(NH2)-N(CH3)-CH2-CO-NH-R∗X, where R is aminoacid residual of aliphatic, aromatic or heteroaromatic amino acid or its derivative, representing pharmaceutically acceptable salts of amino acids, esters of amino acids, amides of amino acids or peptides; X is low-molecular organic or mineral acid, or water. New substances are produced by interaction of guanydilic agents and sarcosine amides in polar organic solvents at temperature 50°C and less.

EFFECT: new compounds can be used as a neuroprotective agent.

3 cl, 10 ex, 6 tbl

Up!