Multifunctional biocompatible hydrogel and method thereof
The invention relates to the field of medicine and related material for medical purposes, in particular the drive for human and animal cells, implanted in the body of a mammal, or depot for drugs, representing multifunctional biocompatible hydrogel containing cross-linked copolymer of acrylamide, methacrylamide, and a cross-linking agent is 2-hydroxyethyl methacrylate and N,N'-methylene-bis-acrylamide and water, and method of its production by copolymerize these monomers in three stages. 2 N. and 13 C. p. F.-ly, 2 ill., 1 PL.
The technical field,
The invention relates to a formulation and method for producing a biocompatible polyacrylamide hydrogel, which can be used as a material for medical purposes, in particular as a carrier for human and animal cells, implanted in a mammalian organism; as a depot for drugs with long-term medication, such as tumors or abscesses.
It is known that the polyacrylamide hydrogels (PAG) are fairly cheap and easy to manufacture materials and possess chemical and bioleaching and/or soft tissue with minimal trauma for the patient.
In medicine there is a method of treating insulin-dependent diabetes mellitus (EN 2165263) by transplantation of heterogeneous-cells of the pancreas in a pre-introduced to the patient, for example, subcutaneously polyacrylamide gel, around which the formed capsule.
There is also known a method of cultivation of heterogeneous mammalian cells (EN 2152800), in particular Leydig cells and melanoma cells by transplantation in previously introduced mammals polyacrylamide gel.
This opens up the possibility of treatment of diseases by transplantation into a patient heterogeneous cells that produce the necessary enzymes and/or hormones, as well as the implementation of vaccine therapy of cancer.
However, as it was experimentally found that the duration of the production of heterogeneous cells is necessary for the body of the patient substances under other equal conditions depends on the properties of polyacrylamide gel (PAG).
As you know, after implantation of the page in the body of a mammal around him formed a connective tissue capsule (A. B. Shekhter et all "Injectable hydrophilic polyacrylamide gel Formacryl and tissue response to its implantation", in the journal. "Annals of plastic, reconstructionancient in PAG heterogeneous cells and destruction of the implanted cells.
However, not only the presence of a connective tissue capsule affects the duration of the production of heterogeneous cells is necessary for the body of the patient substances.
Known biocompatible polyacrylamide hydrogel, as described in the application EP No. 742022 containing from 3.5 to 9.0 wt.% cross-linked copolymer of acrylamide with a cross-linking agent - methylene-bis-acrylamide and 96.5-a 99.0 wt.% water.
The hydrogel obtained by the method described there (EP No. 742022), which consists in the fact that they are carrying out the reaction of copolymerization of acrylamide with methylene-bis-acrylamide in an aqueous medium in the presence of peroxide initiators of polymerization by exposure of the reaction mixture at room temperature for 20 minutes for cross-linking of the copolymer. The process of copolymerization is carried out in one stage, as the peroxide polymerization initiators, a mixture of ammonium persulfate and tetramethylethylenediamine, and as the water environment take pyrogen-free water or sodium chloride solution.
The hydrogel obtained in this way has an insufficient degree of crosslinking, due to the low temperature of the process copolymerization and its single-stage process. This leads to the rapid germination of the connective tissue and in the ts implantation", in the journal. "Annals of plastic, reconstructive and aesthetic surgery", 1997, No. 2, page 19).
In addition, the thus obtained hydrogel contains unbound molecules tetramethylethylenediamine, free NH2radicals and monomers of acrylamide in amounts of 1.0-1.2 µg per 1 gram of polymer (1,0-1,2 ppm), which may cause the active aseptic inflammatory response in the early stage of injection of the hydrogel in the body (see A. B. Shekhter et all "Injectable hydrophilic polyacrylamide gel Formacryl and tissue response to its implantation", in the journal. "Annals of plastic, reconstructive and aesthetic surgery", 1997, No. 2, page 19).
Known biocompatible hydrogel described in patent RU No. 2127129 containing from 1.0 to 8.0 wt.% cross-linked copolymer of acrylamide with a cross-linking agent - methylene-bis-acrylamide and 92.0-a 99.0 wt.% water. The method of obtaining this material is also described in patent RU No. 2127129 and is copolymerization of acrylamide with methylene-bis-acrylamide in an aqueous dispersion medium in the presence of a peroxide polymerization initiator. At the same time as the water environment taking subjected to electrolysis of water, having a pH of 9.0 to 9.5. The stitching of the copolymer is carried out at incubation of the reaction mixture in two stages: at a temperature of 20-90C for 2-24 hours and who will win tetramethylethylenediamine, contains a little more than 1% of free NH2radicals and monomers of acrylamide in an amount of 0.6-0.8 µg per 1 gram of polymer (0,6-0,8 ppm). However, it is designed and intended primarily for plastics soft tissues and does not provide a sufficient duration of active operation of heterogeneous cells when used as a carrier of implanted cells.
Disclosure of the invention
The main task to be solved by the invention is the increased duration of the active life placed in polyacrylamide hydrogel heterogeneous cells in the body of the recipient.
Another objective is to reduce the degree of resorption of the hydrogel and the possibility of infiltration of macrophages after its implantation in the body of the recipient.
Another objective is to reduce tissue reaction to the implanted hydrogel by reducing the content of free radicals and monomers.
The task is solved by the fact that the proposed multifunctional biocompatible hydrogel containing polyacrylamide and water, which according to the invention as polyacrylamide copolymer contains acrylamide, methacrylamide, 2-hydroxyethylene the components, wt.%:
Specified polyacrylamide is from 3.0 to 10.0 wt.% from the total mass of biocompatible hydrogel.
Specified biocompatible hydrogel contains the following ratio of components, wt.%:
2-hydroxyethylmethacrylate of 0.003 to 0.4
N,N'-methylene-bis-acrylamide - 0,006-0,6
water to 100
As water hydrogel contains twice distilled pyrogen-free water.
Multifunctional biocompatible hydrogel has a pH of 3.5-4.5.
The specified hydrogel convenient for injection and packaged in syringes.
The specified hydrogel convenient for the formation of capsules in the body of animals and humans, for which it is implanted in the human or animal body, and then put him in the desired cell culture.
The tasks are solved in that a method of obtaining multifunctional biocompatible hydrogel by copolymerization of monomers and cross-linking agents in an aqueous medium in the presence of a peroxide initiator polymerization in several stages, in which according to the invention as take monomers acrylamide and methacrylamide, as cross-linking agents take 2-HYDR is p>methacrylamide 0,54-3,0
2-hydroxyethylmethacrylate of 0.003 to 0.4
water to 100
The copolymerization is carried out in three stages: the first stage at a temperature of 20-30With in 12-24 hours, the second stage - by-irradiation at a dose of 0.4 to 1.0 megarad and a third stage at a temperature of 100-130And pressure of 0-1,2 ATM for 20 to 40 minutes.
The specified hydrogel after the first stage copolymerization washed in hot water having a temperature of 70-110With, for at least 3 hours at a mass ratio of the hydrogel and water 1:8-10 and pressure 0-1,2 ATM.
Initiated copolymerization take the hydrogen peroxide and/or ammonium persulfate in an amount not exceeding 0.33 wt.% on the total weight of the starting components.
As the water environment take twice distilled pyrogen-free water.
The resulting hydrogel is placed or Packed in syringes and used for implantation in the human or animal body with the formation of the capsule and the subsequent introduction into the capsule of the desired cell cultures.
The proposed hydrogel can be obtained in different ways and claimed a method of obtaining a polyacrylamide hydrogel in no way ogenyi ways to obtain a hydrogel of this part with certain specified properties.
As you know, the hydrogel containing polyacrylamide, is a three-dimensional network Poperechnaya crosslinking agents monomers in cells which retained water, which contains some unknown number of unbound initiator of polymerization, as some also an unspecified number of the initiator of polymerization directly into the structure of the copolymer (see M. N. Savitskaya, Y. D. Kholodova "Polyacrylamide", Publishing house "Technika" 1969, page 103) or washed out from the hydrogel during washing.
This biologically active properties of this hydrogel largely depend on the mesh structure of the polymer, which in turn depends on the conditions of synthesis, namely qualitative and quantitative ratio of initial reagents, including cross-linking agents and initiators of polymerization, which are chemical and hydrogen bonds are embedded in the structure of the copolymer (groups NH, CH, COOH, NH2CH2), as well as the implementation of polymerization.
The invention consists in the fact that was selected qualitative and quantitative composition of polyacrylamide gel and conditions of the copolymerization, allowing zoom what I get offered polyacrylamide hydrogel was allowed to reduce the amount of unbound amino groups, free NH2radicals and unsaturated double bonds. Also managed to increase the degree of crosslinking due to the formation of structural groups (-H2C-NH-CH2-), (-CO-NH-CR2-O-R), (-CO-NH-NH-CO-), (H-COR-NH-CR-O-R), (-CONH-R-NH-CO), where R is CH3CH2, NH2C2H5C3H7and increasing the number of cross-links - N-N bonds.
All this helped to ensure the high stability of the proposed hydrogel to resorption and shrinkage in the body of the patient and the conditions for experiencing implanted in the gel cells.
A brief description of the illustrations
For a better understanding of the invention examples of specific receiving offer biocompatible hydrogel with reference to the accompanying illustrations, where:
In Fig.1A presents an infrared (IR) absorption spectrum of the proposed hydrogel;
Fig.1B - IR absorption spectrum of the hydrogel of the prototype, produced in the Russian patent RU No. 2127129 under the trade name “Formacel”. Both the IR spectrum made in the field of 4000-500 cm-1(along the axis "x" indicates the wavelength of light (cm-1); axis "y" is the degree of light absorption T (in %).
In Fig.2A shows a photograph of the proposed hydrogel, obtained using scanning (SEM) electron microscopy; F. the boe pictures obtained using an electron microscope Hitachi S 405A.
Examples of carrying out the invention
To obtain the proposed biocompatible hydrogel take:
- acrylamide (acrylamide): C3H5NO, they say. weight 71.08, white crystalline powder, odorless, a melting point of 84.5With; produced by Sigma (Catalogue Reagents for biochemistry and research in the field of natural Sciences SIGMA, 1999, S. 47, catalogue No. A);
- methacrylamide (methacrylamide):3H7NO; mol. weight 73.08, white powder; melting point 111With; produced by Fluka (Fluka Katalogue "Chemica-Biochemica", Fluka AG, Switzerland, 1986/87, p.1151);
- 2-hydroxyethylmethacrylate -(2-hydroxyethylmethacrylate):6H10About3, mol. weight 130.1, liquid; boiling point 205-208S; density of 1.07 g/ml; produced by Sigma (Catalogue Reagents for biochemistry and research in the field of natural Sciences SIGMA, 1999, S. 567, catalogue No. N);
-N,N'-methylene-bis-acrylamide (N,N'-methylene-bis-acrylamide): C7H10N2O2, mol. weight 154,16, white crystalline powder, without odor, melting point 185With production company Sigma (Catalogue Reagents for biochemistry and s the O8-they say. weight 228.19; colorless flat crystals; temperature fracture 120With; produced by Sigma (Catalogue Reagents for biochemistry and research in the field of natural Sciences SIGMA, 1999, S. 117);
- hydrogen peroxide: H2About2- they say.weight 34,0; colourless liquid density at 0With - 1,465; melting point - 0,89With; produced by Sigma (Catalogue Reagents for biochemistry and research in the field of natural Sciences SIGMA, 1999, S. 556, catalogue No. N);
All of the above take monomers suitable for biological purposes and does not require additional purification.
Water taken twice distilled pyrogen-free (pH 5,6).
The method is as follows.
To prepare the reaction mixture is taken twice distilled pyrogen-free water, having a pH of 5.6.
Prepare a water solution containing acrylamide, methacrylamide, 2-hydroxyethylmethacrylate and N,N'-methylene-bis-acrylamide, taken in the ratio 65,0-80,0:18,0-30,0:0,1-4,0:0,2-6,0.
The total mass of the initial monomers in the solution is from 3.0 to 10.0 percent (varying the number of initial monomers in the mixture, get the hydrogel of different density and elasticity).
In the resulting solution is injected initiators is x a mixture in any proportion and number not exceeding the sum of their maximum values. Varying the amount of hydrogen peroxide and ammonium persulfate, receive material having a desired pH in the range 3.5 to 4.5.
Finished, the reaction mixture was filtered through a bactericidal polymer filters, for example, the brand F8273 with pore size of 0.45 mm CA/CN, manufacturer Sigma (USA), and placed for copolymerization of monomers for incubation at a temperature of 20-30With in 12-24 hours. After this incubation produce washing of the hydrogel, already having the form of gel, hot water, why put the gel in a container of water having a temperature of 70-110C, at a pressure of 0-1,2 ATM, and the ratio of the volume of gel and water 1:8-10 4-6 hours.
Then spend the second stage copolymerization, the processing intermediateirradiation at a dose of 0.4 to 1.0 megarad. After this semi-finished product Packed in the required amount in vials or syringes and spend the third stage copolymerization, maintaining the gel at a temperature of 120C and a pressure of 1.2 ATM for 20-40 minutes.
Were held physico-chemical, sanitary-chemical and Toxicological studies of samples of the proposed hydrogel in accordance with ISO 10993 "Assessment Biol is new and latex medical products" (Ministry of health of the USSR, M., 1988) and the recommendations of the "Allowable amount of migration of chemical substances that leach from plastics and other materials in contact with food hydrogels, and methods of their definition of" SanPiN 42-122-42-40-86.
The determination of the content in samples obtained hydrogel monomers of acrylamide and N,N'-methylene-bis-acrylamide was performed in accordance with the methodology described in the work of V. V. Kuznetsov et al. “Determination of Acrylamide in Polyacrylamidic gels"// The 52-nd Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy. -New Orleany, LA, 2001, Abstract Book No. 1648.
These studies it was found that the proposed hydrogel has the following physicochemical characteristics:
- Appearance - gel;
- Color - colorless to translucent dark brown, opalescense;
Is the refractive index - 1,328-1,360;
- Density - 1,0-1,2 g/cm3;
- pH 3,5-4,5;
The content of monomers to 0.4 ppm;
The level of broniruete - not more than 1,0 (mg bromine per 1l). Sanitary-chemical tests showed that
- migration of the metals cu, Fe, Ni, Zn, Al, Ti, Ag in aqueous extract of hydrogel, determined by atomic absorption method is not found within the sensitivity of the method(0,02; 0,05; 0,05; 0,02; 0,005; 0,04 mg/l, respectively), which is well below acceptable levels adopted for drinking water is the cue trials showed that aqueous extract of hydrogel showed no hemolytic effect in experiments in vitro with isolated rabbit erythrocytes. Installed hemolysis 0.04% of the permissible value of 2%.
In the acute experience on white mice in injecting a hydrogel samples at a dose of 50.0 ml per 1 kg of body weight there were no deaths in animals and clinical signs of intoxication: common condition experienced mice, their behavior, eating food, coat condition did not differ from control.
At autopsy experienced mice established that tissue at the site of injection of the hydrogel, regional lymph nodes, internal organs (liver, kidney, spleen) were within the physiological norm and control.
No statistically significant differences in the dynamics of body weight, clinical and biochemical blood indices, coefficients of internal organs in the experimental animals compared to control after subcutaneous implantation of the gel for a period of 2.5 months.
Not detected sensitizing effect of hydrogel when performing an immunological diagnostic reaction degranulation of mast cells (RTC).
Micronuclear test for drugs bone marrow is not installed mutagenic effect of hydrogel. Histologic is Alo the presence of a mild tissue reaction to the hydrogel in the first days after implantation and the absence of dystrophic and necrotic changes in the organs.
The following are specific examples of the preparation of the proposed biocompatible hydrogel and its application for the cultivation of heterogeneous cells in the body of the recipient.
To obtain a hydrogel took 384 ml twice distilled pyrogen-free water, having a pH of 5.6, and was dissolved therein 11.2 g of acrylamide, 3.6 g of methacrylamide, of 0.48 g of 2-hydroxyethylmethacrylate and 0.72 g of N,N'-methylene-bis-acrylamide, suitable for biological purposes. Then in the original solution was brought 0.04 g of ammonium persulfate and 2 ml of 30% hydrogen peroxide. The resulting mixture was filtered through a bactericidal polymer filter brand F8273 with pore size of 0.45 mm CA/CN, manufacturer Sigma (USA), and placed in a container which was placed for incubation in a water bath at a temperature of 30With over 22 hours.
Then the hydrogel in the form of a gel was washed in hot water with the ratio of water and gel 10:1 at a temperature of 90within 4 hours and spent the second stage copolymerization, the processing intermediateirradiation at a dose of 0.8 megarad. After this intermediate was packaged in syringes of 0.5 to 3.0 ml and perform the third stage copolymerization, maintaining the gel at a temperature of 120C and pressure is from.% acrylamide have to 22.5 wt.% methacrylamide, 0.3 wt.% 2-hydroxyethylmethacrylate and 0.4 wt.% N,N'-methylene-bis-acrylamide and has a pH of 4.3.
The sample obtained hydrogel has the following physicochemical characteristics:
Appearance: colorless, translucent, opalescent gel;
The refractive index - 1,348;
the pH of 4.3;
The density is 1.0 g/cm3;
The content of monomers 0.1 ppm;
The level of broniruete - 0,1 (mg bromine per 1 liter).
Were obtained IR spectrum and the electron-microscopic examination of the dried sample of the hydrogel, are presented respectively in Fig.1A and 2A.
For comparison in Fig.1B and Fig.2B presents the IR spectrum and chromatogram of an extract known hydrogel prototype, produced in the Russian patent RU No. 2127129 under the trade name “Formacel”, which contains 96 wt.% the aqueous phase and 4 wt.% copolymer, where 96 wt.% acrylamide has to 4.0 wt.% N,N'-methylene-bis-acrylamide, has a pH of 5.4, the level of broniruete of 0.27 (mg bromine per 1 l), and obtained by incubation of the mixture in the presence of hydrogen peroxide and ammonium persulfate in a total amount of 0.3 wt.% at a temperature of 60C for 12 hours and then at 100 ° With another 2 hours.
As can be seen from the spectrum shown in Fig.1A, which are available NH2radicals, which could form coordination with the structural grid of the hydrogel.
As can be seen from the spectrum shown in Fig.1B, there is a band - 1620 cm-1that indicates the presence of NH2radicals in the amount of slightly more than 1%.
For carrying out electron microscopic studies stated hydrogel and hydrogel “Formacel samples of the gels obtained, as described in this example was dried to constant weight. When the samples were taken form the film. The structure of the hydrogels was investigated by the method of scanning (SEM) electron microscopy using electron microscope Hitachi S 405A, which carried out the preparation method of the chip frozen in liquid nitrogen dried samples of hydrogels. Before viewing by scanning electron microscopy on the surface of the samples deposited gold.
Electron microscopic (SEM) pictures of the proposed hydrogel and hydrogel “Formacel” presented respectively in Fig.2A and 2B.
As can be seen from the comparison shown in Fig.2 photos, the proposed hydrogel has a more fine structure compared with hydrogel “Formacel”.
The use of the hydrogel for the and subcutaneously in a volume of 1 ml of the mice S Black. After 1.5 months in the implanted gel, around which is formed a connecting-woven capsule, made of cells of human melanoma lines SKMEL-1 at 1 million cells per capsule with a hydrogel.
After 3, 6 and 9 months of gel kapule was removed from the animals and tested the viability and physiological activity in these capsules of human melanoma cells.
It is established that the cells of the human melanoma line SKMEL-1 remains viable even after 9 months of cultivation in the capsule of the proposed hydrogel.
When translating selected from the capsules of melanoma cells in culture was determined using a standard method of polymerase chain reaction full identity conservative myoglobin human melanoma cells cultured in a nutrient medium, and the cells cultured for 9 months. in the capsule of the hydrogel implanted in the body of the mouse.
This example shows the possibility of long-term cultivation with the help of the proposed hydrogel implanted cells in the body of the recipient while maintaining their viability.
The use of the hydrogel for the cultivation of porcine Leydig cells in the human body for lichenification connective woven gel capsule around it made Leydig cells obtained from Mature pigs.
The testosterone level in the blood of patients was determined using a diagnostic kit company Homemedia (Russia) according to the manufacturer's instructions.
The testosterone level in patients after implantation them porcine Leydig cells presented in the table.
As can be seen from this table, the proposed hydrogel enables cultivation of porcine Leydig cells in the human body when storing these cells ability to synthesize testosterone for 22 months, while during implantation of the cells in the gel-prototype (formail) their ability to active synthesis of the hormone begins to decline in 10 months.
The use of the hydrogel for the cultivation of heterogeneous cells of the pancreas in the human body for the treatment of insulin dependent diabetes mellitus
1. Patient F., 37 years. Insulin-dependent diabetes mellitus diagnosed 11 years ago, one year after childbirth.
Pregnancy, the patient proceeded hard: with toxemia second half of pregnancy, nevropatologii, much to 26 kg weight gain. The disease wore all the years of unstable character that trabado 30 IU/day. In the last two years diagnosed with pathological changes in the kidney, which is defined as diabetic nephropathy. In the analysis of urine increased upper bound of proteinuria 10-12 times. The increase in blood pressure up to 170/110 mm RT.article.
Obtained as described in example 1, the hydrogel implanted in this patient. After the formation of connective woven gel capsule around it introduced the culture of cells in the pancreas of newborn rabbits.
Already 7 days after injection of the cells of the pancreas, the patient had improvement in General condition, reduced sense of thirst and dryness of oral mucosa, reduce blood pressure to 140/90 mm RT.article After 15 days the patient's condition has reduced the need for exogenous insulin from 30 to 18 units (blood and urine). After 30 days, the need for exogenous insulin decreased to 12 IU/day, and by the end of the 2nd month up to 4 meals/day.
After introduction of the cells of the pancreas, the patient is observed for 12 months. Clinical manifestations of nephropathy is not detected, the blood pressure within the age norm. The patient was transferred to oral antidiabetic drugs with a prerequisite of sobludenia. Insulin-dependent diabetes mellitus diagnosed 18 years due to severe stressful situation. The nature of the disease was first unstable heavy. Doses of exogenous insulin reached 70 IU/day. Over time, the nature of the disease has stabilized, but the deterioration occurred after stressful situations and errors in diet.
In the last three years was noted deterioration of the vessels of the lower extremities, decreased libido, decrease in erection quality and sexual intercourse. Diagnosed diabetic angiopathy of the lower extremities and the penis. The need for exogenous insulin over the last year from 20 to 40 IU/day.
Obtained as described in example 1, the hydrogel implanted this patient. After the formation of connective woven gel capsule around it introduced a culture of pancreatic cells 14-day-old piglets.
Two weeks after injection of cells of the pancreas, the patient noted improvement in General condition. One month later the need for exogenous insulin decreased to 12 IU/day. After 2 months - up to 6 units/day. 4 months after transplantation the patient was transferred to oral antidiabetic drugs. Normal sexual life of the patient, considerable is tov, data of additional methods of investigation (blood, urine) allow you to talk about high efficiency of treatment of diabetes by introducing heterogeneous pancreatic cells in the hydrogel of the proposed structure.
therapeutic effect lasts, as a rule, from 10 to 20 months depending on the severity of the disease. The number of transplanted cells is also determined by the severity of diabetes, in particular the amount of sick of exogenous insulin.
Thus, examples of specific performance show that the proposed biocompatible hydrogel can be obtained by using the proposed method.
The proposed hydrogel practically does not cause tissue reaction, does not cause sensitization of the organism, does not cause dystrophic and necrotic changes and can be used for implantation in the body of animals and humans for the formation of capsules and subsequent cultivation in her desired cell cultures.
Compared with the known hydrogel-prototype (hydrogel “Formacel”) in the structure of the proposed hydrogel are no free NH2radicals, which could form co more fine structure and provides the possibility of more long-term cultivation of implanted cells in the body of the recipient with preserving their viability and ability to produce necessary products, in particular testosterone and insulin.
1. Multifunctional biocompatible hydrogel containing polyacrylamide and water, characterized in that it contains polyacrylamide cross-linked copolymer of acrylamide, methacrylamide and cross-linking agent is 2-hydroxyethyl methacrylate and N,N'-methylene-bis-acrylamide.
2. Multifunctional biocompatible hydrogel under item 1, characterized in that the specified polyacrylamide contains the following ratio of components, wt.%:
2-Hydroxyethyl methacrylate 0,1-4,0
N,N'- Methylene-bis-acrylamide 0,2-6,0
3. Multifunctional biocompatible hydrogel under item 1, characterized in that it contains the specified polyacrylamide from 3.0 to 10.0 % of the total mass of biocompatible hydrogel.
4. Multifunctional biocompatible hydrogel under item 1, characterized in that it contains the following ratio of components, wt.%:
2-Hydroxyethyl methacrylate 0,003-0,4
N,N'- Methylene-bis-acrylamide 0,006-0,6
Water To 100
5. Multifunctional biocompatible hydrogel under item 4, characterized in that the quality of the water it contains twice distilled pyrogen-free water.
6. Multifunctional hydrogel under item 1, characterized in that it is suitable for injection.
8. Multifunctional biocompatible hydrogel under item 1, characterized in that it is suitable for the formation of capsules in the tissues of animals and humans.
9. Multifunctional biocompatible hydrogel under item 1, characterized in that it is suitable for cultivation heterogeneous (allogeneic or xenogeneic) or autologous cells.
10. Multifunctional biocompatible hydrogel under item 7, characterized in that it is packaged in syringes.
11. The method of obtaining multifunctional biocompatible hydrogel by copolymerization of monomers and cross-linking agents in an aqueous medium in the presence of a peroxide initiator polymerization in several stages, wherein as monomers take acrylamide and methacrylamide, as cross-linking agents take 2-hydroxyethyl methacrylate and N,N'-methylene-bis-acrylamide in the following ratio, wt.%:
2-Hydroxyethyl methacrylate 0,003-0,4
N,N'- Methylene-bis-acrylamide 0,006-0,6
Water To 100
the copolymerization is carried out in three stages: the first stage at a temperature of 20-30C for 12-24 h, the second stage - by-irradiation at a dose of 0.4 to 1.0 Mrad and p. 11, characterized in that the hydrogel after the first stage copolymerization washed in hot water having a temperature of 70-110With, for at least 3 h at a pressure of 0-1,2 ATM. and the mass ratio of the hydrogel and water 1:8-10.
13. The method according to p. 11, characterized in that as the initiator of the copolymerization take the hydrogen peroxide and/or ammonium persulfate in an amount of not more than 0.33 % of the total weight of the starting components.
14. The method according to p. 11, characterized in that the quality of the aquatic environment take twice distilled pyrogen-free water.
15. The method according to p. 11, characterized in that the hydrogel is Packed into syringes.
FIELD: organic chemistry.
SUBSTANCE: invention relates to methods for stabilizing compounds based on benzimidazole or its physiologically acceptable salt. One variant of a method involves incorporation of crospovidone having small diameter of particles and at least one compound taken among sodium hydroxide and potassium hydroxide into benzimidazole-base compound represented by the formula (1):
wherein Het1 means:
R1 and R2 are similar or different and taken among hydrogen atom, methoxy- and difluoromethoxy-group; R3 is taken among hydrogen and sodium atom; R4, R5 and R6 are similar or different and taken among group comprising hydrogen atom, methyl, methoxy-, methoxypropoxy- and trifluoroethoxy-group, or its physiologically acceptable salt. Other variants involve applying at least one compounds taken among sodium hydroxide and potassium hydroxide on core formed by incorporation of crospovidone into benzimidazole-base compound represented by the formula (1) or its physiologically acceptable salt, enteric soluble coating, or intermediate coating and the following applying additional enteric soluble coating on it. Also, invention relates to a method for prevention of the benzimidazole-base compound color change or its physiologically acceptable salts and this method involves incorporation of crospovidone and at least one compound taken among sodium hydroxide and potassium hydroxide into benzimidazole-base compound by cl. 1, or its physiologically acceptable salt.
EFFECT: improved stabilizing method.
7 cl, 2 tbl, 8 ex
FIELD: medicine, pharmacy.
SUBSTANCE: invention relates to a solid pharmaceutical composition. The composition comprises tegaserod or its salts as an active component that is sensitive to acid effect and/or difficultly soluble in water, and a loosening agent taken in the amount at least 15 wt.-% as measured for the total mass of the composition. The composition is stable and can be prepared easily, it shows good rate release after its administration patients and good biological availability. The composition is designated for prophylaxis, modulation or treatment of visceral pain or discomfort, for modulation of visceral sensitivity or perception, improvement of sensory perception of rectum intestine tension and for treatment of anal dysfunction regulation.
EFFECT: improved and valuable medicinal properties of composition.
14 cl, 7 ex
FIELD: medicine, endocrinology, pharmaceutical technology, pharmacy.
SUBSTANCE: invention relates to nateglynide-containing preparation used in treatment of diabetes mellitus that comprises nateglynide as an active component and a carrier wherein nateglynide in amorphous form and indicated carrier represents hydrophilic material. Amorphous property of crystalline nateglynide is provided by the following methods: 1) by dissolving nateglynide crystals in pharmacologically acceptable solvent in common with hydrophilic materials taken among the group consisting of water-soluble polymers, water-swelling polymers, sugar alcohols and salts followed by granulation in fluidized layer, granulation by stirring at high rate, drying by spraying and process for coat applying for granulation of amorphous nateglynide; 2) by mixing nateglynide crystals with hydrophilic materials taken among the group of water-soluble polymers, water-swelling polymers, sugar alcohols and salts and the following application of the high shift force to the prepared mixture; 3) by mixing nateglynide crystals with hydrophilic materials taken among the group of water-soluble polymers, water-swelling polymers, sugar alcohols and salts and the following plasticizing the prepared mixture in melt by heating and milling at cooling; 4) by dissolving nateglynide crystals in pharmacologically acceptable liquid additives wherein liquid additives represent water-soluble polymers that are liquid at 37°C. Using amorphous nateglynide allows preparing the nateglynide preparation with immediate release wherein the dissolving rate of medicinal agents is high and without crystalline transition during preparing or preserving preparations.
EFFECT: valuable pharmaceutical properties of preparation.
6 cl, 3 tbl, 9 dwg
FIELD: medicine, dermatology, pharmacy.
SUBSTANCE: invention relates to a pharmaceutical gel composition for applying on skin. The composition comprises at least one vitamin D or analog of vitamin D, at least one corticosteroid, at least one solvent and an excipient enhancing viscosity. Viscosity value of the composition is in the range from 5 mPa x s to 500 mPa x s. The composition is designated for treatment of psoriasis and associated states in humans. The composition is suitable for applying on skin, shows the improved absorption and stable at 40°C in storage for 3 months.
EFFECT: improved and valuable properties of composition.
22 cl, 2 tbl, 1 ex
SUBSTANCE: composition has hydrophilic gel produced from chitosan and hydrophilic poly(N-vinyl lactame) having kinematic viscosity index less than 60. When deposited on cracks, the gel absorbs exudate undergoing no structural transformations.
EFFECT: improved skin compatibility properties.
FIELD: medicine, obstetrics, gynecology.
SUBSTANCE: due to instrumental technique one should pre-detect the volume of uterine cavity and its longest length against the cervix. Moreover, it is necessary to fix a woman's body in position at which the upper edge of uterine cavity bottom is below against the lower edge of uterine cervical opening till the moment of complete filling in uterine cavity with blood. With the help of a catheter one should introduce medicinal preparation heated up to +42- +45° C into uterine cavity through an opening in uterine cervix into area of cavitary bottom at the volume exceeding the half of cavitary volume. Moreover, as the above-mentioned medicinal preparation it is necessary to apply dehydrated silicone gel impregnated with equal volume of 3%-hydrogen peroxide solution. The innovation enables to interrupt postpartum hypotonic uterine hemorrhage efficiently and safely.
EFFECT: higher efficiency.
FIELD: medicine, pharmacy.
SUBSTANCE: invention relates to a pharmaceutical composition for controlled release that comprises a medicinal agent, polyethylene oxide with molecular mass 2000000 Da or above and a special size-regulating agent for indicated polyethylene oxide and wherein indicated medicinal agent and size-regulating agent are dispersed uniformly in polyethylene oxide. Also, invention relates to a method for preparing indicated pharmaceutical composition for controlled release and a pharmaceutical preparation for controlled release comprising indicated pharmaceutical composition for controlled release. The pharmaceutical composition with controlled release possesses good uniformity of the content and can be prepared using polyethylene oxide powder particles showing properties suitable for making tablets that is prepared by uniform dispersing a size-regulating agent for polyethylene oxide.
EFFECT: improved and valuable pharmaceutical properties of composition.
32 cl, 1 tbl, 16 ex