RU2637653C1 - Method for production of pharmaceutical compositions based on polymeric nanoparticles by microfluid technology - Google Patents

Abstract

FIELD: pharmacology.

SUBSTANCE: method includes passage of an aqueous solution containing polyvinyl alcohol and an acetone or acetonitrile solution of etoposide or niklozamide and a biodegradable polymer in the form of a copolymer of lactic and glycolic acids with an intrinsic viscosity of 0.41-1.0 dL/g and molar ratio of monomer units of 25 and 75 to 75 and 25%, or a mixture thereof with the medical polymethylmethacrylate Eudragi through a flow-through microreactor made of borosilicate glass, preliminarily, an aqueous solution of polyvinyl alcohol is passed through a flow-through microreactor made of borosilicate glass at a concentration of 0.5 to 1% by volume in an amount of 1-100 volumes of the microreactor heated to a temperature of 55-65°C, followed by microreactor cooling to room temperature.

EFFECT: stability of particle size distribution relative to the mean value and exclusion of the possibility of particles aggregation during their formation.

2 cl, 5 dwg, 4 tbl, 2 ex

Description

State of the art

In modern science and production, nanotechnology is a combination of technologies and techniques that allow the manipulation of individual atoms and molecules on a scale of 1-100 nanometers in one dimension. In the practical aspect, nanotechnology is the technology for the production of devices and their components necessary for the creation, processing and manipulation of nanoparticles.

The innovative method of microfluidic flow technology for producing and functionalizing nanoparticles for medical and pharmaceutical purposes is a special case of microfluidic technologies. Technically, it all comes down to replacing standard reactors (one of the main types of equipment in chemical and pharmaceutical industries) with capillary ones. The fundamental difference between microstructured (capillary) reactors and standard volume reactors is the laminar motion of fluid flows (liquids and gases).

Laminarity is determined by a dimensionless quantity — the Reynolds number, which is directly proportional to the diameter of the capillary, the flow rate and the density of the liquid, and inversely proportional to the viscosity. Experimental data show that when working with liquid media with standard values of density and viscosity, it is possible to use capillaries with an inner diameter of up to 4 mm, without exceeding a critical Reynolds number of 2300.

Proceeding from this, the use of capillaries predetermines an almost ideal mixture of reagents due to diffusion, and their design features allow the pressure and temperature of the internal medium to be varied in the same way. The small volume and large surface area make it possible to very quickly supply and remove heat to and from the reactor, practically eliminating the phenomenon of a temperature gradient in the volume of the medium in the reactor. The strength characteristics of the reactors are such that a significant increase in pressure (10 to 100 times higher than atmospheric) does not lead to the destruction of the reactor and, moreover, does not require the observance of generally accepted structural and organizational safety measures required when operating pressure vessels.

In contrast to turbulent mixing of reagents in volumetric mode, mixing in a laminar flow almost completely eliminates the formation of concentration and temperature gradients in volume and time. Ideal diffusion mixing predetermines high selectivity and purity of the reaction, and, as a result, a significant reduction in the formation of by-products and intermediates. In the case when chemical transformations do not occur in the reactor, the advantages described above can be used to obtain, for example, polymer nanoparticles with a uniform fractional composition and high yield of the finished product while minimizing labor costs (A. Gerbst, V.V. Shudegov, R.F. Yarullin, L. Nazemtseva, Nanotechnology and Microreactors - Parallels in Development // Bio- and Nanotechnologies, No. 3 (16) May 2012, P. 78-88.) [1].

The closest known method for producing polymer micron and submicron particles using microfluidic flow technologies, given in the authors DR Raimov, V.V. Suslov PRODUCTION OF POLYMERIC MICRON AND SUBMICRON PARTICLES USING MICROFLUID FLOW TECHNOLOGIES // Advances in Chemistry and Chemical Technology. VOLUME XXIX. 2015. No. 10, pp. 118-119. [2].

Describes how to obtain particles from a copolymer of lactic and glycolic acid (mass ratio of monomers in the polymer 50/50), in the form of separate fractions, the average particle size of which is from 0.7 to 4.5 microns. The resulting particles are of interest from the point of view of pharmaceutical technology, because can be loaded with various medicinal substances and, after parenteral or enteral administration into the body, act as a drug with controlled release.

The method consists in the fact that by means of a microfluidic installation, an aqueous 2.5% (mass.) Solution of polyvinyl alcohol and a 0.5% (mass.) Solution of a copolymer of lactic and glycolic acid in an organic solvent, immiscible or simultaneously, are fed into a flowing microreactor (chip) limited to miscibility with water (chloroform, methylene chloride). Selecting the feed rates of the aqueous and non-aqueous - organic phases, an emulsion was obtained, after removal of the volatile solvent from which micron and submicron particles were obtained. Data regarding the conditions for obtaining particles described in the source [2] are shown in table 1.

The described method has the following disadvantages:

- upon receipt of particles of submicron size, the yield of particles sharply decreases or, accordingly, the volume of the solution for evaporation increases;

- used solvents are limitedly mixed with water, which creates some problems during evaporation;

- the resulting particles of submicron size are large enough, for practical use, particles are preferred whose average size is about 500 nm or less.

Microfluidic technologies make it possible to obtain heterogeneous systems (emulsions, suspensions) with smaller particles, but it is necessary to ensure optimal conditions in the process of particle formation in a microreactor. Due to the design features of microreactors, the ratio of the contact area to the volume of the reaction mixture of microreactors is many times greater than the contact area in volumetric reactors. The specific surface area of microstructural reactors is calculated from 10,000 to 50,000 m ² / m ³ , while traditional reactors reaches a maximum of 100 m ² / m ³ [1]. Therefore, it is necessary to take into account the processes taking place at the interface between the two phases (liquid / liquid, solid / liquid), where the solid is not only the forming particles, but also the wall of the reactor. The influence of surface tension forces and the degree of wettability of the material of the wall of the reactor have a direct effect on the shape, size and fractional composition of the resulting particles. Ways to influence the factors listed above are reduced either to the introduction of surfactants into the composition of the media to produce particles, or to modification of the surface of the reactor wall. A combination of these methods is also possible. In the case of pharmaceutical technology, the choice of surfactants is limited to substances approved for human use.

One of the most common methods for modifying the surface of a wall of reactors is its hydrophobization by chemical methods. Similar methods are applicable for microreactors, such as borosilicate glass. Shui, L., van den Berg, A. and Eijkel. J.C.T. (2009) 'Interfacial tension controlled W / O and O / W 2-phase flows in microchannel', Lab Chip, 9: 795-801 [3] describes a typical sequence of steps to obtain such a coating. The resulting coatings are considered permanent and indelible. The process proceeds in several stages, as a result of which a layer with the required properties is formed on the surface. The material of the layer and the wall material are chemically bonded to each other. During processing, hydrogen is replaced in the surface —OH group by a hydrophobic radical. The reaction proceeds as a nucleophilic substitution and can be schematically represented as follows:

-Si-OH + Cl-Si-R → -Si-O-Si-R + HCl,

where -Si-OH is the wall surface of the glass capillary with a hydroxide group;

Cl-Si-R is any halogenated organosilane with pronounced hydrophobic properties, for example, C ₁₀ H ₄ Cl ₃ F ₁₇ Si (FDTS - perfluorododecyl trichlorosilane, CAS # 78560-44-8).

The sequence of actions for obtaining coverage is as follows:

1. The microreactor is washed with water, the remaining water is removed by drying under vacuum;

2. The microreactor is washed with isopropyl alcohol, the remaining alcohol is removed by drying under vacuum;

3. The microreactor is washed with a 30% hydrogen peroxide solution, the remaining hydrogen peroxide is removed by drying under vacuum;

4. The microreactor is washed with a 2% (or other concentration) solution of organochlorosilane in a non-polar solvent, for example isooctane);

5. Excess organochlorosilane is removed by washing with a solution of isooctane;

6. The microreactor is washed sequentially with isopropanol and ethanol;

7. The microreactor is kept under vacuum when heated to 110 ° C to remove residual alcohols and hydrochloric acid released during the reaction.

The process described above is applicable only to glass surfaces and, in addition to the surface material, has limitations associated with the chemical structure of the grafted hydrophobic substance.

The methods closest to microfluidic technologies for modifying the surface of a microreactor without the formation of a layer chemically bonded to the reactor wall can be considered the methods used for capillary electrophoresis to coat the inner surface of capillaries with polyvinyl alcohol. The capillary cross section is close to the cross sections of microreactors; similar materials (glass) are used to create them. The purpose of creating such a coating is to reduce the interaction between the capillary material and the analyzed sample (various proteins, DNA fragments, etc.).

Analysis of Nucleic Acids by Capillary Electrophoresis [4] describes a method for applying a temporary coating, which reduces to the fact that a 0.05% solution of polyvinyl alcohol (PVA) in a buffer solution is passed through a capillary. The coating is hydrophilic and meets the requirements for it. From a practical point of view, it will be unstable and the capillary will require re-treatment with a PVA solution before each analysis.

The method of applying a permanent coating of PVA is reduced to treating the capillary with a 10% aqueous solution of PVA followed by immobilization of the PVA on the surface of the capillary in a stream of nitrogen at 140 ° C for several hours. The resulting coating is considered permanent and indelible. It does not require subsequent treatments with a buffer solution containing PVA before each analysis [4].

Both methods of coating from PVA do not lead to the formation of a coating chemically bonded to the capillary wall, but the result is either an unstable or permanent (difficult to remove) coating.

Also known are methods for producing a PVA-based coating chemically bonded to the surface of a capillary (Tohei Moritani, Kyunghwan Yoon, Miriam Rafailovich, Benjamin Chu. DNAcapillary electrophoresis using polyvinyl alcohol. I. Inner capillary coating. Electrophoresis 2003, 24, 2764-2771) [5] . The scheme of its deposition as a whole repeats the scheme of applying a chemically bound hydrophobic coating described in [3]. The difference is that the synthesis step of the silanol derivative of PVA is added. The same authors showed the possibility of obtaining a capillary wall coating hydrolytically stable over a wide pH range with a more stable —Si — С— bond obtained by the Grignard reaction (Shabarov Yu. S. Organic chemistry: In 2 books. - M .: Chemistry , 1994. - 352 s: ill.) [6]. The scheme for obtaining such a coating includes a separate stage for producing a magnesium-halogen derivative of PVA.

Among the disadvantages of the described methods for producing coatings, it is worth noting the high complexity, the impossibility of subsequent removal of the coating and the need for thorough cleaning of the microreactor after receiving the coating from reaction by-products.

Thus, the currently known methods for processing the internal surfaces of capillaries, applicable including and in microreactor technologies, they come down either to the formation of non-removable capillaries chemically associated with the material (the methods are suitable only for glass capillaries) coatings, or to the formation of hard-to-remove coatings by holding the capillary for a long time in an inert atmosphere under the influence of elevated temperatures, or to the formation of extremely unstable coatings, the use of which in the case of a long-time installation does not justify itself. A serious obstacle to the formation of chemically bonded coatings can be the microreactor material, which can be made not only of glass, but also of metals and their alloys [1].

For pharmaceutical applications, it is of interest to apply a moderately resistant coating, which should not be significantly destroyed (washed off) during the process, but if necessary, could be removed by available methods using low-toxic and easily removable reagents in the future. The second important factor is the simplicity and convenience of applying such a coating without dismantling the microreactor and without the need for subsequent removal of by-products formed during the formation of the coating, as such products are toxic to the human body and will definitely affect the formation of nanoparticles. Moreover, the choice of materials for coating formation is extremely limited; PVA remains the most promising from this point of view due to its technological properties, biological inertness and the absence of toxic effects in the doses used.

Based on the foregoing, the objective of the invention is to develop a method for producing nanoparticles using microfluidic technology, which involves creating a coating on the wall of a microreactor without the use of additional reagents and processes that are time-consuming, includes lengthy operations for coating and subsequent cleaning of a flow microreactor from residues of reagents and by-products of reactions that can cause contamination of the resulting particles, while effectiveness to the stability of particle size distribution relative to the average value, the size of nanoparticles in the range of 200-400 nm, and removing the possibility of aggregation of the particles during their formation.

To this end, a method for producing pharmaceutical compositions based on polymer nanoparticles by the microfluidic technology is proposed, which consists in passing through a flow microreactor made of borosilicate glass, an aqueous solution containing polyvinyl alcohol and a solution in etone or acetonitrile of etoposide or niclosamide and a biodegradable polymer in the form of a milk and glycolic acid with a characteristic viscosity of 0.41-1.0 dl / g and a molar ratio of monomer units of 25 and 75 to 75 and 25%, or a mixture thereof with a polymer tilmethacrylate for medical use Eudragit, while an aqueous solution of polyvinyl alcohol with a concentration of 0.5 to 1% by volume in an amount of 1-100 volumes of a microreactor heated to a temperature of 55-65 ° C, followed by cooling, is preliminarily passed through a flowing microreactor from borosilicate glass microreactor to room temperature.

Besides:

- the pharmaceutical composition is a finished dosage form in the form of sterile or non-sterile lyophilisates for subsequent dissolution and preparation of suspensions for injection, or inhalation, or tablets, or capsules, or granules, or aerosols, or powders, or ointments.

The technical result is achieved by the fact that an additional stage of processing the inner surface of the flowing microreactor with a surface-active substance, which has a high

adhesion to the surface of the flow microreactor and is part of the pharmaceutical composition for producing nanoparticles. Such a substance can be a solution of polyvinyl alcohol in concentrations from 0.5 to 1.0% by volume, which is introduced into the microreactor before the start of nanoparticle production and under the influence of elevated temperature due to adhesion creates a coating on the inner surface of the microreactor that is acceptable from the point of view of operational properties, which, if necessary, can be removed, the pharmaceutical composition in addition to polyvinyl alcohol will contain etoposide, niclosamide or other active pharmaceutical substances or mixtures thereof, used in pharmaceutical practice, a biodegradable polylactide glycolide polymer (lactic acid glycolic acid copolymer - PLGA) or other similar substances, polymethimethacrylate (Eudragit), approved for medical use or similar substances. Pharmaceutical compositions obtained by the above method as shown below have an average particle size in the range from 200 to 400 nm.

In FIG. Figure 1 presents data on the distribution of particle sizes of PLGA by volume (histogram). The curve shows the relative number of particles whose sizes are below the specified limit. Data obtained for a borosilicate glass microreactor without any pre-processing.

In FIG. Figure 2 presents data on the distribution of particle sizes of PLGA by volume (histogram). The curve shows the relative number of particles whose sizes are below the specified limit. The data were obtained for a borosilicate glass microreactor through which a PVA solution was previously passed.

In FIG. Figure 3 presents data on the distribution of particle sizes of PLGA by volume (histogram). The curve shows the relative number of particles whose sizes are below the specified limit. The data obtained for the microreactor of borosilicate glass which was treated with a PVA solution by the proposed method.

Figure 4 presents data on the distribution of particle sizes containing a pharmaceutical composition with etoposide (histogram). The curve shows the relative number of particles whose sizes are below the specified limit. Nanoparticles contain etoposide in a carrier polymer PLGA 50/50. To obtain particles, a microfluidic setup with a reactor that underwent processing of the internal surface of PVA was used.

In FIG. 5 presents data on the size distribution of particles containing a pharmaceutical composition with etoposide (histogram). The curve shows the relative number of particles whose sizes are below the specified limit. The nanoparticles contain niclosamide in the carrier polymer PLGA 50/50 and Eudragit (Eudragit RS PO). To obtain particles, a microfluidic setup with a reactor that underwent processing of the internal surface of PVA was used.

A study was made of the formation of particles in a microreactor. As a polymer for the preparation of unloaded particles, a polylactide glycolide copolymer (PLGA) with a 50/50 ratio of lactic and glycolic acid copolymers was used. Prepared 1% (mass.) Solutions in an organic solution (acetonitrile). The second solution is 1% (mass.) Aqueous solution of PVA. It is known that particles obtained using the above solutions are distinguished by a homogeneous fractional composition and an acceptable (small) size. The resulting particles are promising from the point of view of their use in medicine and pharmacy (A. Gerbst, S.A. Kedik, D.R. Raimov, E.S. Zhavoronok, E.A. Petrova, A.V. Panov, V.V. Suslov, L. Griner, L. Nazemtseva Microreactor systems for microencapsulation in pharmacy. // Development and registration of medicines - 2014. - Issue 4 (9). - P. 76-85.) [7]. In contrast to the known method (Xie and Smith: Fabrication of PLGA nanoparticles with a fluidic nanoprecipitation system. Journal of Nanobiotechnology 2010 8:18) [8], the Qmix microreactor unit (Wingflow AG, Switzerland), the microreactor volume 0, was used to obtain particles. 4 ml, material - borosilicate glass. The feed rate of the liquid phases was selected experimentally. In the described experiment, it was 1 ml / min for a 1% PVA solution, 0.1-0.2 ml / min for a 1% PLGA 50/50 solution with a similar result.

Polymer particles were obtained, the size of which was determined by laser light diffraction using a Zetasizer Nano instrument (Malvern Instruments Ltd., United Kingdom). The size and distribution of particles by volume were estimated. In FIG. 1 shows a typical distribution for the obtained sample. The presence of a micron-sized fraction and the fact that 95% of the total particle volume are less than 1090 nm are noteworthy. After washing the microreactor with water and repeated experiments on obtaining particles, similar results were obtained, which indicates a systematically repeating process associated with the interaction of the wall of the microreactor and the solutions entering it.

The experimental conditions were changed and the solution of polyvinyl alcohol began to be fed into the microreactor earlier than the solution of the polymer in an organic solvent. Thus, the aim was to provide preliminary contact of the PVA and subsequent adhesion of a certain amount of PVA on the capillary wall to reduce the likelihood of adhesion of forming polymer particles on the capillary wall. The results are shown in FIG. 2. The result obtained did not differ much from the previous one, but it was noted that 95% of the particles of the total volume are 870 nm in size, ie. a shift in the fractional composition towards a smaller particle size was recorded both in average size and in aggregate.

Experiments where the feed rates and concentrations of PVA and PLGA 50/50 polymer solutions were varied showed that this problem has no obvious solution, because restrictions imposed on the process are often insurmountable, because are associated with the loss of stability of many active pharmaceutical substances with increasing temperature and a decrease in the viscosity of the liquid phases supplied to the microfluidic setup (leads to a significant enlargement of the resulting particles). Also, experiments were carried out using solutions of PLGA polymer in another organic solvent, acetone, under similar conditions. There were no differences in the sizes of the obtained particles from those obtained from a solution in acetonitrile.

A method for producing pharmaceutical compositions has been proposed, comprising treating the inner surface of the microreactor and not requiring dismantling it. The method consists in the fact that the microreactor is processed by the component used for the subsequent production of nanoparticles under certain conditions. Solutions of polyvinyl alcohol of various concentrations (from 0.5% to 2.5%) and the results of their treatment of the inner surface of the reactor were studied. All of these solutions were used to treat the reactor in a similar manner. The best results were obtained for solutions with a PVA content of from 0.5 to 1.0%. The processing was reduced to passing PVA solutions through the microreactor in volumes from 10 to 100 volumes of the microreactor when the microreactor was heated to a temperature of 60 ° C. Heating above this temperature is associated with a risk of disruption of fluid flow through the microreactor due to the formation of gas bubbles (steam). It was found that the result is affected by temperature (processing time decreases with increasing temperature). The flow rate can affect the result when using solutions with a concentration of up to 0.5% PVA; for PVA solutions with a concentration of more than 1%, an increase in the flow rate of more than 1.5 ml / min leads to a significant increase in pressure in the system without any positive effects; therefore, further study of PVA solutions with higher concentrations was considered impractical. Thus, the optimal conditions for processing the microreactor were established: the concentration of the PVA solution from about 0.5 to 1%, the feed rate of the solution from 0.5 to 1 ml / min, heating to 60 ° C, the processing time of 20-40 minutes. The presence of surface modification was determined through analysis of the size of the resulting particles.

Also, an increase in pressure in the system was noted during the passage of water through the treated microreactor compared with the pressure observed during the passage of water at the same flow rate through the untreated microreactor. It was reliably established that after processing the microreactor, the pressure of water passed through it increases on average from 0.05 bar for feed rates of 0.5-0.75 ml / min to 0.075-0.1 bar for a feed rate of 2.5 ml / min (table. 2).

Unloaded polymer nanoparticles and nanoparticles containing active pharmaceutical substances were obtained. The preparation of nanoparticles is illustrated by examples of pharmaceutical compositions based on nanoparticles containing active pharmaceutical substances as having practical value.

Example 1

Obtaining polymer forms of etoposide using microfluidic technology.

Materials:

- A solution of polyvinyl alcohol (Sigma-Aldrich) 0.5% or 1% (prepared immediately before use, filtered under vacuum in hot form through a fiberglass filter with a pore size of 1 μm).

- A solution of etoposide (meets USP requirements) and a copolymer of lactic and glycolic acids PLGA 50/50 (PURAC Biochemicals) in acetone (analytical grade) or in acetonitrile (analytical grade). The etoposide content in the solution is 1 mg / ml (0.1%), the PLGA 50/50 polymer content is 10 mg / ml (1%).

Equipment:

Qmix microreactor installation (Wingflow, Switzerland):

Flowing microreactor: 400 μl volume, borosilicate glass (Wingflow, Switzerland).

Liquid phase feed rate:

- 0.5% or 1% solution of polyvinyl alcohol: 0.5 ml / min or 1 ml / min (coating), then 1 ml / min;

- a solution of etoposide and polymer PLGA 50/50: 0.2 ml / min.

Particle production

The microfluidic installation was turned on, the supply of a 0.5% or 1% polyvinyl alcohol solution was set at a rate of 0.5 or 1 ml / min, the flowing microreactor was heated to 60 ° C, and the polyvinyl alcohol solution was continued for the next 20 or 40 minutes. Then, the flow was stopped until the flowing microreactor was cooled to room temperature. After that, the flow of polyvinyl alcohol was resumed at a rate of 1 ml / min and a solution of etoposide and PLGA 50/50 polymer in acetone or acetonitrile began to be supplied to the unit at a rate of 0.2 ml / min. After the start of feeding the etoposide and polymer solution, the head fraction was collected under pressure control in the system. The onset of suspension formation was recorded by increasing pressure. The head fraction was collected within 3 minutes from the beginning of the increase in pressure and was subsequently discarded. The main fraction was collected before the solutions were consumed.

Next, the main fraction was evaporated under vacuum on a rotary evaporator to remove the volatile organic solvent and part of the water. If necessary, excess polyvinyl alcohol was removed by centrifugation and removal of excess supernatant. Then, the amount of water necessary for resuspension was added to the precipitate and resuspension was carried out using a mechanical shaker or an ultrasonic bath. Next, the previously calculated amount of D-mannitol (cryoprotectant) was added to the resulting suspension. If the centrifugation-resuspension stage was not carried out, a cryoprotectant was added immediately after evaporation on a rotary evaporator. The suspension with a cryoprotectant was frozen in liquid nitrogen and freeze-drying of the suspension was carried out. The finished product is a porous lyophilic mass, which can be used as a finished dosage form, or as an intermediate for its preparation.

The quality of the resulting series was evaluated by the average particle size and polydispersity index (table 3).

Example 2

Obtaining polymer forms of niclosamide using microfluidic technology.

Materials:

- A solution of polyvinyl alcohol (Sigma-Aldrich) 0.5% or 1% (prepared immediately before use, filtered under vacuum in hot form through a fiberglass filter with a pore size of 1 μm).

Pharma Polymers») в ацетоне (ч.д.а.) или ацетонитриле (ч.д.а). Содержание никлозамида в растворе - 1 мг/мл (0,1%), содержание полимера PLGA 50/50 - 6 мг/мл (0,6%), содержание Эудрагита - 4 мг/мл (0,4%).- A solution of niclosamide (meets EP requirements), a copolymer of lactic and glycolic acids PLGA 50/50 ("PURAC Biochemicals") and Eudragit ^® RS PO (Eudragit) ("Evonik

Pharma Polymers ") in acetone (analytical grade) or acetonitrile (analytical grade). The content of niclosamide in the solution is 1 mg / ml (0.1%), the polymer content of PLGA 50/50 is 6 mg / ml (0.6%), the content of Eudragit is 4 mg / ml (0.4%).

Equipment:

Qmix microreactor installation (Wingflow, Switzerland):

Flowing microreactor: 400 μl volume, borosilicate glass (Wingflow, Switzerland).

Liquid phase feed rate:

- 0.5% or 1% solution of polyvinyl alcohol: 0.5 ml / min or 1 ml / min (coating), then 1 ml / min;

- a solution of niclosamide and polymers (PLGA, Eudragit): 0.2 ml / min.

Particle production

The microfluidic installation was turned on, the supply of a 0.5% or 1% polyvinyl alcohol solution was set at a rate of 1 ml / min, the heating microreactor was turned on to 60 ° C and the polyvinyl alcohol solution was continued for the next 20 or 40 minutes. Then, the flow was stopped until the flowing microreactor was cooled to room temperature. After this, the flow of polyvinyl alcohol resumed at the same rate and a solution of niclosamide and polymers (PLGA, Eudragit) in acetone or acetonitrile began to be supplied to the unit at a rate of 0.2 ml / min. After the start of feeding the etoposide solution and the polymers, the head fraction was collected under pressure control in the system. The onset of suspension formation was recorded by increasing pressure. The head fraction was collected within 3 minutes from the beginning of the increase in pressure and was subsequently discarded. The main fraction was collected before the solutions were consumed.

Next, the main fraction was evaporated under vacuum on a rotary evaporator to remove the volatile organic solvent and part of the water. If necessary, excess polyvinyl alcohol was removed by centrifugation and removal of excess supernatant. Then, the amount of water necessary for resuspension was added to the precipitate and resuspension was carried out using a mechanical shaker or an ultrasonic bath. Next, the previously calculated amount of D-mannitol (cryoprotectant) was added to the resulting suspension. If the centrifugation-resuspension stage was not carried out, a cryoprotectant was added immediately after evaporation on a rotary evaporator. The suspension with a cryoprotectant was frozen in liquid nitrogen and freeze-drying of the suspension was carried out. The finished product is a porous lyophilic mass.

The quality of the resulting series was evaluated by the average particle size and polydispersity index (table 4).

As shown above, the invention allows to obtain nanoparticles in the range of 200-400 nm with a uniform distribution of particle sizes relative to the average, which is confirmed by the values of the polydispersity index, not exceeding 0.2. The lyophilisate obtained from nanosuspension is a ready-to-use product. The sterility of the obtained lyophilisate can be achieved both by production under aseptic conditions and by the introduction of an additional sterilization step. The properties of the obtained lyophilisate allow its dissolution with the resuspension of nanoparticles in volume and apply in the form of suspensions for injection, inhalation, external and internal use; tablets, capsules, granules, aerosols, powders and ointments in the composition of the finished dosage forms.

Information sources

1. A. Herbst, V.V. Sudegov, R.F. Yarullin, L. Nazemtseva. Nanotechnology and microreactors are parallels in development. // Bio- and nanotechnology, No. 3 (16) May 2012, S. 78-88.

2. D.R. Raimov, V.V. Suslov PRODUCTION OF POLYMERIC MICRON AND SUBMICRON PARTICLES USING MICROFLUID FLOW TECHNOLOGIES // Advances in Chemistry and Chemical Technology. TOM XXIX. 2015. No. 10, pp. 118-119.

3. Shui, L., van den Berg, A. and Eijkel. J.C.T. (2009) 'Interfacial tension controlled W / O and O / W 2-phase flows in microchannel', Lab Chip, 9: 795-801.

4. Heller, Christoph. Analysis of Nucleic Acids by Capillary Electrophoresis. Braunschweig: Vieweg, 1997. Print., 143.

5. Tohei Moritani, Kyunghwan Yoon, Miriam Rafailovich, Benjamin Chu. DNAcapillary electrophoresis using polyvinyl alcohol). I. Inner capillary coating. Electrophoresis 2003, 24, 2764-2771.

6. Shabarov Yu.S. Organic chemistry: In 2 kn. - M .: Chemistry, 1994 .-- 352 s: silt.

7. A. Herbst, S.A. Kedik, D.R. Raimov, E.S. Lark, E.A. Petrova A.V. Panov, V.V. Suslov, L. Griner, L. Nazemtseva. Microreactor systems for microencapsulation in pharmacy // Development and registration of medicines - 2014. - Issue 4 (9). - S. 76-85.

8. Xie and Smith: Fabrication of PLGA nanoparticles with a fluidic nanoprecipitation system. Journal of Nanobiotechnology 2010 8:18.

Claims (2)

1. A method of producing pharmaceutical compositions based on polymer nanoparticles by microfluidic technology, consisting of passing through a flow microreactor made of borosilicate glass, an aqueous solution containing polyvinyl alcohol and a solution of etoposide or niclozamide in acetone or acetonitrile and a biodegradable polymer in the form of a milk glycol copolymer acids with a characteristic viscosity of 0.41-1.0 dl / g and a molar ratio of monomer units of 25 and 75 to 75 and 25%, or a mixture thereof with polymethyl methacrylate d I have a medical use of Eudragit, in this case, an aqueous solution of polyvinyl alcohol with a concentration of 0.5 to 1% by volume in an amount of 1-100 volumes of a microreactor heated to a temperature of 55-65 ° C, followed by cooling of the microreactor, is passed through a borosilicate glass microreactor first. to room temperature. 2. The method according to p. 1, characterized in that the pharmaceutical composition is a finished dosage form in the form of sterile or non-sterile lyophilisates for subsequent dissolution and preparation of suspensions for injection, or inhalation, or tablets, or capsules, or granules, or aerosols, or powders, or ointments.

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