Liposomal suspensions stabiliser

FIELD: pharmacology.

SUBSTANCE: conjugate of the invention is a compound of formula (C6O4H9NH2)m(C6O4H9NHX)n, wherein the remainder of the polyethylene glycol derivative, which is a monomethoxy-PEG succinate acts as a substituent on the amino group X, the molecular weight of chitosan used to prepare the conjugate is 15 to 120,000 daltons, am and n are the number of units in the molecule, where m/n is 6 to 19. The proposed method involves preparation of a solution of N-hydroxysuccinimide ester of PEG-hemisuccinate in dimethylformamide or dimethylsulfoxide, mixing of the solution prepared with an acidic solution of chitosan with a molecular weight of 15-120 kDa, and adjustment of the resulting mixture to a pH of 7.5-8.0, followed by purification by dialysis against buffer solution.

EFFECT: new substance effective for liposomal suspensions stabilization is disclosed, and an effective method for its preparation.

3 cl, 3 dwg, 4 ex

 



 

Same patents:

FIELD: medicine.

SUBSTANCE: on completion of the antibacterial course, sodium hyaluronate in the form of a gel is single administered by means of a syringe with a needle of 2 cm long or more under an oral mucosa along a transitory fold into the points within projections of apexes of dental roots 1.4, 2.4, 3.6, 4.6 and into a point on the mid-line of projections of apexes of anterior roots of upper and lower jaw respectively. The needle is brought under the mucosa on the lower jaw by transecting the projections of an alveolar counterfort line. On the upper jaw - by transecting the projections of the upper counterfort line. While removing the needle from the mucosa, the syringe content is squeezed out. Sodium hyaluronate is administered into both jaws in an amount of 3.0 to 4.4 ml.

EFFECT: method enables increasing the jaw bone density within counterforts, as well as soft and bone tissues of periodontium.

4 tbl, 16 dwg, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to obtaining chitosan. The method includes preliminary processing of a natural chitin-containing raw material for the separation from it of the material, which is not enriched with chitin by processing with a weak sodium hydroxide solution with the further separation and washing of the chitin-containing raw material. After that, the chitin-containing raw material is demineralised by submerging into a 0.5-2 M solution of hydrochloric acid at a temperature from 20°C to 30°C for 0.5-2 hours, the raw material is separated, washed for 0.5-2 hours and then separated from washing water. Then, the demineralised chitin-containing raw material is subjected to deproteinisation by processing in a 1-10% sodium hydroxide solution for 4-24 hours at a temperature from 60°C to 80°C, the deproteinised raw material is separated, washed for 0.5-2 hours and separated from washing water. After that, residual water is separated from the chitin raw material and the latter is submerged into a deacetylating 40-50% sodium hydroxide solution with carrying out deacetylation at a temperature from 90°C to 110°C for 1-3 hours. Then, the obtained chitosan biopolymer is separated from the deacetylating solution, washed and separated from washing water. Residual water is separated from the chitosan biopolymer. The biopolymer is dried in air at a temperature not higher than 65°C until the moisture content in the biopolymer reduces to less than 10 wt %. The obtained chitosan is characterised by the deacetylation degree of 80% or higher, protein content less than 0.3%, ash content less than 0.2% and moisture content less than 10%.

EFFECT: invention makes it possible to obtain chitosan of a medical purification degree and does not require additional bleaching stages.

12 cl, 7 dwg, 3 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a novel compound - N,O-(2,3-dihydroxypropyl)chitosanyl-borate, having formula , where m=500-3000.

EFFECT: compound has antibacterial, immunomodulating and antitoxic effect.

1 tbl, 6 ex

FIELD: chemistry.

SUBSTANCE: invention relates to producing chitosan from chitin and can be used in medicine, chemical, textile, paper and food industry. The method comprises crushing chitin to particle size of 1-2×2-3 mm; deacetylation of chitin in a double-neck reactor in 40% NaOH solution with in ratio to chitin of (1-3):(20-60) at 100°C, pressure of 300 mm Hg for 1-2 hours, wherein the double-neck reactor is fitted with a reflux condenser and is connected to a vacuum water-jet pump.

EFFECT: invention improves the degree of acetylation of chitosan and preserves the natural structure of the finished product.

2 tbl, 1 dwg

FIELD: medicine.

SUBSTANCE: there are described compositions containing hyaluronic acid with a low degree of modification of functional groups, and mixtures prepared by a controlled reaction of this slightly modified hyaluronic acid with applicable difunctional or polyfunctional cross-linking agents. The compositions possess the low anti-inflammatory properties in injection in vivo and can be used as medical devices, biomedical adhesives and sealing matters.

EFFECT: targeted delivery of the bioactive substances.

49 cl, 14 dwg, 24 tbl, 45 ex

FIELD: biotechnology.

SUBSTANCE: method of production of the water-soluble bioactive nanocomposite comprising salt of hyaluronic acid modified by citric acid or salt of citric acid, as a matrix, and gold nanoparticles as the filler is carried out by chemical interaction of solid-phase powders of salt of hyaluronic acid, citric acid or salt of citric acid and aurichlorohydric acid or salt of gold under the temperature from -18° to 125°C, under conditions of simultaneous action of pressure from 50 to 1000 MPa and the shear deformation in a mechanochemical reactor.

EFFECT: invention enables to obtain water-soluble bioactive nanocomposite with reliably predictable characteristics, namely the high yield of the target product, high gold content, controlled size of gold nanoparticles, narrow distribution by size of nanoparticles of gold, significant increase in resistance of the composite during long storage the above parameters of the composite are maintained for at least one year, the method is carried out in the absence of the liquid medium and does not require the stage of purification and concentration.

20 cl, 18 ex

FIELD: chemistry.

SUBSTANCE: invention relates to natural polysaccharide polymers and can be used in medicine. The obtained water-soluble bioactive nanocomposite includes a melanin compound-modified hyaluronic acid salt as a matrix and gold nanoparticles as filler. The method includes chemical reaction of solid-phase hyaluronic acid powder, a melanin compound, aurichlorohydric acid or a gold salt in conditions of simultaneous pressure action in the range of 50 to 1000 MPa and shearing deformation in a mechanochemical reactor at temperature of -18° to 110°C.

EFFECT: invention enables to obtain a water-soluble bioactive nanocomposite with high output of the end product and high content of gold.

4 cl, 18 ex

FIELD: chemistry.

SUBSTANCE: stabiliser includes modified chitosan which is obtained by modifying chitosan particles located in an emulsion of an organic solvent - water, with pH 6.0-6.5, by first reacting a mixture consisting of a carboxylic acid in an organic solvent and a condensing agent, and then with an organic base, wherein the carboxylic acid used is either palmitic acid or stearic acid or dodecanoic acid, the condensing agent used is a mixture of hydroxysuccinimide and an aliphatic carbodiimide or formaldehyde and an aliphatic isocyanide, and the organic base used is triethylamine.

EFFECT: effective liposome composition stabiliser which can be obtained using a simple method.

8 cl, 3 tbl, 5 ex, 7 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to the field of organic synthesis. A method of obtaining a water-insoluble sulphur-containing chitosan-based biopolymer includes interaction of chitosan with a thiomethylating agent, preliminarily obtained by saturation of a formaldehyde solution with gaseous H2S, with molar ratio chitosan: formaldehyde: hydrogen sulphide 1:6:4, at a temperature of 60°C for 20-25 hours.

EFFECT: invention ensures obtaining the water-insoluble sulphur-containing chitosan-based biopolymer, which possesses a complexing activity to ions of noble metals (Pd, Pt).

1 ex, 1 tbl

FIELD: biotechnologies.

SUBSTANCE: skins of pond fish are flushed with cold flushing water during 10-15 minutes. They are crushed to the size of 2-3 mm. Water extraction is performed at the temperature of 40-45°C during 40-50 minutes at the ratio of crushed skins to water, which is equal to 1:1 at periodic mixing. Then, they are filtered; liquid fraction is dried in a spraying drier at the drier outlet product temperature of 60-65°C during 15-25 minutes so that hyaluronic acid is obtained. Solid fraction is subject to bleaching during 12 hours with hydrogen peroxide-salt solution that is prepared by mixing of 1 l of 3% hydrogen peroxide and 20 g of sodium chloride. Treatment of bleached solid fraction is performed with 1.0-1.2% solution of sodium hydroxide during 24 hours at the temperature of 20-25°C with further neutralisation of the obtained mixture with 3% boric acid solution. Treatment of swollen solid fraction is performed with Pancreatin ferment preparation solution taken in the quantity of 0.5-0.6% to the weight of solid fraction during 1.5-2.0 hours at the temperature of 37-40°C. Flushing of solid fraction is performed with cold flushing water for removal of Pancreatin residues so that collagen is obtained. The obtained collagen, depending on the purpose, is supplied for drying in drying chambers with forced air circulation at the temperature of 18-20°C during 12 hours and storage in dry ventilated rooms at the temperature of not higher than 20°C during 24 months or frozen to the temperature of minus 18 - minus 20°C and stored at the temperature of minus 18 - minus 20°C during 24 months. The liquid fraction dried in the spraying chamber is stored at the temperature of 0-4°C during 12 months or dissolved in physiological buffer solution.

EFFECT: improvement of the method.

2 dwg, 1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to methods of obtaining and modification of a hyaluronan derivative, containing an aldehyde group in position (6) of a glucosamine polysaccharide fragment. Claimed is a hyaluronic acid derivative. The derivative is oxidised by position 6 of the glucosamine fragment to the aldehyde (formula X)

.

Its hydrated form is called geminal diol (formula Y)

.

A method of obtaining the said hyaluronic acid derivative includes the interaction of hyaluronic acid with Dess-Martin periodinane (DMP) in a polar aprotic solvent. As the polar aprotic solvent, dimethylsulphoxide is preferably used. A method of modification of the obtained hyaluronic acid derivative is also claimed. The oxidised hyaluronic acid derivative is subjected to interaction with an amine of the general formula H2N-R or with hyaluronan, substituted with the group -R-NH2, where R is an alkyl with a linear or branched C1-C30 chain and optionally contains aromatic and heteroaromatic groups.

EFFECT: invention makes it possible to obtain the hyaluronic acid derivative with different possibilities of further modification due to the aldehyde group.

16 cl, 14 ex

FIELD: food industry.

SUBSTANCE: method involves girasol tubers milling, extraction and juice separation. Then obtained juice is subjected to sequential ultrafiltration on AP-2 semi-fibre filters with pores sized 1.2 - 1.8×10-6 m and AP-6 filters with pores sized 0.2 - 0.4×10-6 m. The produced concentrate with dry substances content equal to 20-22% is cleared on ion-exchange columns till inulin content in the concentrate is equal to 20-21%. Before extraction one performs pulp blanching at a temperature of 70±2°C during 15 minutes. Extraction with water is performed with usage of vibration impact, oscillation frequency f=6.6-23 Hz and amplitude A=5 mm during 30-60 min. According to the more preferable version, milled raw material mixing with water during extraction is performed with water duty equal to 1:4.

EFFECT: invention allows to increase inulin yield, reduce its colourity and decrease expenditures.

2 cl, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to chemical industry and can be used in integrated processing of wood. The method for integrated processing of larchwood includes breaking down crushed wood material in a rotary-oscillatory apparatus in three steps, where at the first step the wood raw material is treated with an aliphatic alcohol at 58-60°C, followed by cooling to 30°C and separating the obtained pulp into a liquid phase and a solid phase. The aliphatic alcohol is distilled from the liquid phase. The thick residue is extracted with hexane, filtered to obtain a solid component and a liquid component; hexane is distilled from the liquid component and evaporated at low pressure to obtain wood oil. The solid component is extracted with methyl-tert-butyl ether to obtain a filtrate and wood resin; the filtrate is evaporated in a vacuum, dissolved in deionised water, crystallised, filtered and dried to obtain dihydroquercetin. The solid phase is treated with water in the rotary-oscillatory apparatus at 90-95°C for 12-3 minutes, separated to obtain a wood mass and a filtrate which is precipitated with an alcohol, filtered and dried to obtain arabinogalactan. The obtained wood mass is treated in the rotary-oscillatory apparatus while adding an aqueous emulsion of latex at 50°C for 2-3 minutes to obtain a modified wood biopolymer.

EFFECT: invention provides fuller processing of larchwood to obtain arabinogalactan, dihydroquercetin, wood oil and resin, as well as a modified wood mass using an affordable process scheme and extract wood products of high quality.

6 cl, 2 dwg, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to polymer xanthan gum. Xanthan gum has the following properties in solution: a) viscosity at low shear rate at 3 rev/min higher than approximately 1600 mPa s, when hydration is carried out in standard tap water with concentration of xanthan gum 0.25 wt %, b) viscosity in sea water higher than approximately 20 with concentration 1 lb/bbl (2.86 kg/m3), when hydration is carried out in synthetic sea water, c) rate of hydration lower than approximately 3 minutes in 1 wt % NaCl solution with 1 wt % concentration of xanthan gum and d) ability of in fact be completely hydrated within less than approximately 10 minutes in 6 wt % NaCl solution with 1 wt % concentration of xanthan gum. Organism, applied for fermentation with obtaining xantham gum, as a rule, represents strain Xanthomonas campestris pathovar campestris.

EFFECT: xanthan gum has improved properties, such as improved resistance to hydration, hydration rates and/or viscosity characteristics in comparison with traditional xanthan gum, with simultaneous preservation of favourable properties of xanthan gum, such as fermentative stability and resistance to shear load.

19 cl, 10 dwg, 4 tbl

FIELD: chemistry.

SUBSTANCE: method includes the interaction of arabinogalactan with a sulphating complex sulphaminic acid-urea in dimethylsulphoxide with continuous mixing and a temperature of 75-85°C for 2.0-3.0 hours. The product is extracted after the neutralisation of the reaction mixture by an ammonia water solution by sedimentation in ethyl alcohol with the following purification by dialysis.

EFFECT: method makes it possible to obtain a water-soluble product and increase the environmental friendliness and efficiency of the process with the application of a novel system of reagents.

1 tbl, 12 ex

FIELD: chemistry.

SUBSTANCE: method includes centrifuging alkali-treated seaweed extract at 70-80°C at 10000-14000 rpm for 5-15 minutes; mixing the hot extract with 2-5% surfactants at a temperature in the range of 60-100°C while stirring continuously and allowing settling for 1-10 hours at a temperature in the range of 25-35°C to precipitate the solid agarose mass; decanting the supernatant liquid and washing said mass with water to remove residual surfactants in the solid substance; redissolving the obtained wet mass in a minimum amount of water in the range of 7 to 10% (wt/wt) with respect to the weight of the agarose product and treating with a minimum amount of isopropanol. The ratio of the amount of the agarose sol to the isopropanol is in the range of 1:0.5 to 1:1.5 (wt/wt) for agarose precipitation. Further, the solid product is isolated and dried in a suitable drier to obtain agarose powder. The obtained agarose powder matches the mesh size according to the American standard in the range of 200 to 300. The seaweed used is selected from Gracilaria and Gelidiella species, preferably Gracilaria dura and Gelidiella acerosa of Indian Ocean water obtained from the Gujarat and Tamil Nadu coasts. Said surfactant is a nonionic surfactant and is selected from commercially available octyl phenol ethoxylate (Triton X-100) and nonyl phenol ethoxylate (Synperonic 91/6) Said surfactant induces flocculation only when the content of sulphate in agarose is <0.82% (wt/wt), preferably <0.5% (wt/wt) and even more preferably <0.25%.

EFFECT: invention enables to obtain agarose of high quality and reduces power and labour consumption of the method.

7 cl, 3 dwg, 5 tbl, 28 ex

FIELD: chemistry.

SUBSTANCE: method of pectin extraction with high degree of polymerisation includes addition of oxalic acid and/or water-soluble oxalate in water suspension which contains peel pectin. Oxalic acid and/or water-soluble oxalate is added until mixture with pH in the range between 3.0 and 3.6 is obtained. The total molarity of oxalate must be more than the total molarity of calcium (II) in peel. Then mixture is heated to temperature from 50 to 80°C for the time, sufficient for pectin extraction. Then extracted pectin is separated from mixture by sedimentation. In other version of method after heating mixture is subjected to unessential filtering to remove insoluble solid substances and then mixture is brought in contact with cation-exchange resin. Extracted pectin is separated from mixture by sedimentation with obtaining pectin output relative to peel more than 23%. Output of pectin (YP) is evaluated by formula YP=0,1·yS·M/WP (I), where yS represents output of liquid extract in g/kg, M represents the total mixture weight before separation of extracted pectin and WP represents weight of peel applied in water suspension. Invention makes it possible to obtain pectin with degree of etherification (DE), at least, 72, high degree of polymerisation and intrinsic viscosity higher than 6.5 dl/g.

EFFECT: increase of polymerisation degree and viscosity.

20 cl, 7 dwg, 3 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: in the claimed method sulphated derivatives of arabinogalactan, separated from larix sibirica wood, are obtained by the interaction of arabinogalactan in a solvent with a sulphating agent with continuous mixing and a stable temperature not higher than +50°C for not more than 12 hours with the following separation, purification and drying of the product, as the sulphating mixture applied is dry potassium persulphate (K2S2O8) in a solution of dimethylsulphoxide. Claimed is a novel effective method, which makes it possible to obtain sulphated AG derivatives both in acidic and in salt forms. A degree of biopolymer macromolecule substitution in terms of the quantitative sulphur content constitutes 9.3-14.2%.

EFFECT: obtained sulphated AG derivatives preserve structural organisation, water solubility and membranotropism of a natural polysaccharide and demonstrate a pharmacological activity.

4 cl, 1 dwg, 3 ex

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to oligosaccharide carrier conjugates effective for treating and preventing infectious diseases and containing an oligosaccharide conjugated with the carrier through a linker of formulas

VIIIa

or

VIIIb:

wherein n is more than 1, m is specified in 1-10, p is specified in 1-20 and R represents H or alkyl; the linker is bound to an oligosaccharide oxygen atom through a terminal CH2 group, and the linker is bound through a terminal CO group with an amino group of the carrier compound by an amide bond; the oligosaccharide is β-1-6 related glucosamine, and the carrier is peptide, protein, polysaccharide, nucleic acid, lipid or tetanus toxoid.

EFFECT: there are presented new conjugates effective to stimulate the immune response, and a method for preparing them.

21 cl, 12 ex, 23 dwg, 1 tbl

FIELD: biotechnologies.

SUBSTANCE: modified capsular saccharide includes linker of the following formula: -A-N(R1)-L-M (I). With that, A represents -C(O)- or -OC(O)-. R1 is chosen from H or C1-C6-alkyl. L represents group of C1-C12-alkene. M represents a masked aldehyde group. Besides, the invention proposes other versions of modified saccharide, versions of a saccharide modification method, a conjugate of saccharide-protein and a pharmaceutical composition. Preferably, a new linker is used to obtain saccharide conjugates Neisseria meningitidis of serogroup A.

EFFECT: invention allows obtaining conjugates with a new linker, which have improved immunising capacity.

10 cl, 3 dwg

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to the chemical-pharmaceutical industry and represents a substance-delivering carrier for the substance delivery to a bone marrow cell producing an extracellular matrix containing retinoid as a delivering agent, wherein the substance is a therapeutic agent, which inhibits the beginning, progression and/or recurrence of myelofibrosis.

EFFECT: invention provides the effective inhibition of the beginning, progression and recurrence of myelofibrosis.

10 cl, 14 dwg, 8 ex

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