High-flux double-emulsion micro-fluidic chip, chip and preparation method of drug microspheres

Abstract

The invention relates to the field of drug delivery, in particular to a high-flux double-emulsion micro-fluidic chip, a chip and a drug microsphere preparation method.The micro-fluidic chip comprises a chip body, a plurality of micro-fluidic unit structures are integrated in the chip body, and each micro-fluidic unit structure comprises an outer water phase flow channel, an oil phase flow channel, an inner water phase flow channel and a discharge flow channel; the oil phase flow channel and the inner water phase flow channel intersect to form a water-in-oil microsphere forming position and extend to form a water-in-oil microsphere flow channel, the outer water phase flow channel and the water-in-oil microsphere flow channel intersect to form a water-in-oil-in-water microsphere forming position, and the discharge flow channel is connected with the water-in-oil-in-water microsphere forming position. According to the high-flux double-emulsion micro-fluidic chip and the chip preparation method, the quality of the micro-fluidic chip can be improved, the technological process is simplified, and the manufacturing cost of the micro-fluidic chip is reduced; the drug microspheres prepared by using the micro-fluidic chip not only can improve the encapsulation efficiency and the high drug loading capacity, but also can further improve the yield of the drug microspheres while ensuring the uniform and controllable particle size.

Description

Technical Field

[0001] The present application relates to the field of drug delivery, and in particular to a high-throughput double-emulsion microfluidic chip, a chip and a method for preparing drug microspheres. Background Art

[0002] Drug microspheres are microspheres with biocompatible, degradable polymer materials as carriers, with drugs adsorbed on the surface or encapsulated inside. The particle size is usually 1 to 250 μm. Due to the large particle size, they generally enter the body through subcutaneous injection or intramuscular injection. After the drug microspheres enter the body, the carrier is gradually dissolved and decomposed, and the encapsulated drugs are slowly released and absorbed by the human body.

[0003] Drug microspheres have the advantages of stable drug properties, targeting, sustained and controlled release, reduced irritation, high efficiency and safety, and are widely used in the medical field. Drug microspheres can be used to treat tumors. Anticancer drugs are encapsulated in microspheres and delivered to the tumor site in a targeted manner to improve the treatment effect and avoid damage to healthy tissues in the body. Microspheres can be used as carriers of vaccines. Through the vaccine delivery system, the human immune response can be improved, effectively extending the shelf life of the vaccine. Drug-loaded microspheres have important applications in the treatment of chronic diseases such as diabetes and cardiovascular diseases. Through the sustained release mechanism of microspheres, the drug concentration in the body can be kept constant. In addition, drug microspheres are also widely used in the treatment of mental illness, blocking opioid dependence, etc., and have broad market application prospects.

[0004] The main methods for preparing drug microspheres on the market include emulsification, phase separation, spray drying, hot melt extrusion, etc. These methods have the advantages of simple preparation process and large output, but the particle size uniformity of the prepared drug microspheres is poor and requires screening. In addition, for some water-soluble drugs that are difficult to dissolve in organic solvents, these methods are limited by technical conditions during the preparation process, resulting in the process becoming cumbersome or even unable to obtain the target drug microspheres. Microfluidic technology is a process that drives immiscible continuous phase and dispersed phase to flow and intersect in the channel through pressure, relying on the extrusion / shearing effect of the continuous phase on the dispersed phase to cause the interface to be unstable and break, and generate dispersed microspheres. Microfluidic technology can be used to prepare drug microspheres with uniform and controllable particle size, which plays an important role in improving the stability of the efficacy of drug preparations. However, this technology still needs to be further optimized and improved in terms of the preparation process and cost of microfluidic chips, as well as the output of drug microspheres. Currently, commonly used microfluidic chip materials include PDMS, glass, and single-crystal silicon wafers, but the preparation process of these chips mainly adopts etching, micro-injection molding, etc., which has a complex preparation process and high cost. The traditional preparation process is limited by technical conditions, and the chip structure design freedom is poor, making it difficult to prepare complex high-integration chips, thereby limiting its ability to prepare high-throughput drug microspheres, especially for water-soluble drug microspheres, which are usually prepared in the form of water-in-oil-in-water (W / O / W). Since its preparation difficulty is further increased compared to water-in-oil (O / W), the requirements for structural design are also higher.

[0005] To this end, the present invention is proposed. Summary of the invention

[0006] The main purpose of the present invention is to provide a high-throughput double-emulsion microfluidic chip, a chip and a method for preparing drug microspheres, aiming to solve at least one of the above technical problems.

[0007] To achieve the above-mentioned purpose, the present invention proposes a high-throughput double-emulsion microfluidic chip, comprising: a chip body, wherein a plurality of microfluidic unit structures are integrated inside the chip body, and each of the microfluidic unit structures is a water-in-oil-in-water (W / O / W) template; each of the microfluidic unit structures comprises an external water phase flow channel, an oil phase flow channel, an internal water phase flow channel and a discharge flow channel, the oil phase flow channel and the internal water phase flow channel intersect to form an oil-in-water microsphere formation site and extend to form an oil-in-water microsphere flow channel, the external water phase flow channel and the oil-in-water microsphere flow channel intersect to form a water-in-oil-in-water microsphere formation site, and the discharge flow channel is connected to the water-in-oil-in-water microsphere formation site.

[0008] In some embodiments of the present invention, an external aqueous phase separation tube, an oil phase separation tube, an internal aqueous phase separation tube and a collecting tube are formed in the chip body, and an external aqueous phase total inlet connected to the external aqueous phase separation tube, an oil phase total inlet connected to the oil phase separation tube, an internal aqueous phase total inlet connected to the internal aqueous phase separation tube and a total outlet connected to the collecting tube are formed on the surface of the chip body; the inlet of the external aqueous phase flow channel of each microfluidic unit structure is respectively connected to the external aqueous phase separation tube, the inlet of the oil phase flow channel is respectively connected to the oil phase separation tube, the inlet of the internal aqueous phase flow channel is respectively connected to the internal aqueous phase separation tube, and the inlet of the discharge flow channel is respectively connected to the collecting tube.

[0009] In some embodiments of the present invention, a plurality of the microfluidic unit structures are arranged in a single layer or multiple layers in the chip body.

[0010] In some embodiments of the present invention, the widths of the flow channels where the water-in-oil microspheres are formed and where the water-in-oil-in-water microspheres are formed are 25 to 100 μm, respectively.

[0011] To achieve the above-mentioned purpose, the present invention also proposes a chip preparation method for the above-mentioned high-throughput double-emulsion microfluidic chip, comprising the following steps: designing a high-throughput double-emulsion microfluidic chip using three-dimensional drawing software; preparing the designed high-throughput double-emulsion microfluidic chip using integrated 3D printing technology; cleaning excess resin material of the prepared high-throughput double-emulsion microfluidic chip using a cleaning solution; preparing a hydrophilic layer in each flow channel inside the high-throughput double-emulsion microfluidic chip; and connecting the high-throughput double-emulsion microfluidic chip to an interface.

[0012] In some embodiments of the present invention, the processing accuracy of the integrated 3D printing is 2 to 10 μm.

[0013] In some embodiments of the present invention, the preparation of the hydrophilic layer includes: successively using piranha solution and potassium hydroxide / sodium hydroxide aqueous solution to treat each flow channel inside the high-throughput double-emulsion microfluidic chip to form a hydrophilic layer; or adding 5-10% emulsifier to the resin material of the 3D printed high-throughput double-emulsion microfluidic chip, and obtaining the hydrophilic layer after printing and cleaning.

[0014] To achieve the above-mentioned purpose, the present invention also proposes a method for preparing drug microspheres, using the above-mentioned high-throughput double-emulsion microfluidic chip or the high-throughput double-emulsion microfluidic chip prepared by the above-mentioned chip preparation method to prepare microspheres, comprising the following steps: preparing inner water phase, oil phase, and outer water phase solutions; using a microfluidic pressure pump to inject the inner water phase, oil phase, and outer water phase into the high-throughput double-emulsion microfluidic chip at a certain flow ratio to obtain water-in-oil-in-water drug microspheres; dispersing the drug microspheres into a receiving liquid for solidification; cleaning the solidified drug microspheres; freeze-drying the drug microspheres and storing them.

[0015] In some embodiments of the present invention, the components of the inner aqueous phase include water-soluble drugs, protective agents, suspending agents and deionized water.

[0016] In some embodiments of the present invention, the oil phase includes a biocompatible, degradable polymer material and an oil phase solvent; and the external aqueous phase is a polyvinyl alcohol solution.

[0017] Compared with the prior art, the present invention achieves the following technical effects:

[0018] 1. The highly integrated multi-channel double-emulsion microfluidic chip provided by the present invention can prepare drug microspheres with uniform and controllable particle size, and can achieve high-quality preparation of drug microspheres in the form of water-in-oil-in-water (W / O / W), which plays an important role in improving the stability of the efficacy of drug preparations, and can achieve high-throughput preparation of water-soluble drug microspheres, greatly improving the production efficiency of drug microspheres with good repeatability.

[0019] 2. The present invention adopts integrated 3D printing technology to prepare a high-throughput double-emulsion microfluidic chip, which has the advantages of simple processing technology, low cost, and convenience for large-scale production; based on the integrated 3D printing technology, the chip structure design has a high degree of freedom, and complex high-integration chips can be prepared, thereby improving the ability to prepare high-throughput drug microspheres, especially for water-soluble drug microspheres, which are usually prepared in the form of water-in-oil-in-water (W / O / W). Although the preparation difficulty is more difficult than water-in-oil (O / W), the high-throughput double-emulsion microfluidic chip prepared by the present invention using integrated 3D printing technology can efficiently, conveniently and ensure the quality of water-in-oil-in-water water-soluble drug microspheres.

[0020] 3. The present invention improves the hydrophilic treatment scheme of the inner surface of the flow channel of two microfluidic chips, the hydrophilic effect is long-lasting, and the high-throughput double-emulsion microfluidic chip has good repeatability.

[0021] 4. The prepared core-shell structured drug microspheres have uniform and controllable particle size, high drug loading capacity and high drug encapsulation rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0023] Figure 1 A top view of a high-throughput double-emulsion microfluidic chip provided by the present invention;

[0024] Figure 2A front view of a high-throughput double-emulsion microfluidic chip provided by the present invention;

[0025] Figure 3 A flow chart of a high-throughput double-emulsion microfluidic chip and a method for preparing drug microspheres provided by the present invention;

[0026] Figure 4 A diagram showing the formation process of PLGA-leuprorelin microspheres provided by the present invention;

[0027] Figure 5 A structural diagram of a PLGA-leuprorelin microsphere provided by the present invention;

[0028] Figure 6 An optical microscope image (A) and a particle size distribution diagram (B) of PLGA-leuprorelin microspheres provided by the present invention.

[0029] The reference numerals in the accompanying drawings represent as follows: 1. total inlet of external aqueous phase; 2. total inlet of oil phase; 3. total inlet of internal aqueous phase; 4. total outlet; 5. external aqueous phase separatory tube; 6. oil phase separatory tube; 7. internal aqueous phase separatory tube; 8. collecting tube; 9. upper unit structure; 10. formation place of water-in-oil microspheres; 11. formation place of water-in-oil-in-water microspheres; 12. lower unit structure; 13. internal aqueous phase; 14. oil phase; 15. external aqueous phase; 16. gelatin; 17. leuprorelin; 18. PLGA. DETAILED DESCRIPTION

[0030] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0031] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0032] In the description of the present application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated before and after are in an "or" relationship.

[0033] The present application discloses a high-throughput double-emulsion microfluidic chip. Figure 1 and Figure 2 As shown, the high-throughput double-emulsion microfluidic chip includes a chip body, and a plurality of microfluidic unit structures are integrated inside the chip body, and each microfluidic unit structure is a water-in-oil-in-water (W / O / W) template.

[0034] Each microfluidic unit structure includes an external water phase flow channel, an oil phase flow channel, an internal water phase flow channel and a discharge flow channel. The oil phase flow channel and the internal water phase flow channel intersect to form an oil-in-water microsphere forming location 10 and extend to form an oil-in-water microsphere flow channel. The external water phase flow channel and the oil-in-water microsphere flow channel intersect to form a water-in-oil-in-water microsphere forming location 11. The discharge flow channel is connected to the water-in-oil-in-water microsphere forming location 11.

[0035] By using the high-throughput double-emulsion microfluidic chip in the technical solution, a microfluidic pressure pump is used to inject the inner water phase 13, the oil phase 14, and the outer water phase 15 into the high-throughput double-emulsion microfluidic chip at a certain flow ratio, such as Figure 3 As shown, first, at the water-in-oil microsphere formation location 10, the oil phase 14 squeezes / shears the inner water phase 13 to form water-in-oil microspheres, and then at the water-in-oil-in-water microsphere formation location 11, the outer water phase 15 squeezes / shears the water-in-oil microspheres to form water-in-oil-in-water microspheres, i.e., drug microspheres, thereby preparing drug microspheres with uniform and controllable particle sizes, achieving high-quality preparation of drug microspheres in the form of water-in-oil-in-water (W / O / W), which plays an important role in improving the stability of the efficacy of drug preparations, achieving high-throughput preparation of water-soluble drug microspheres, greatly improving the production efficiency of drug microspheres, and having good repeatability.

[0036] It should be understood that the number of microfluidic unit structures of the high-throughput double-emulsion microfluidic chip of the present invention can be more than 2, for example, the number of microfluidic unit structures is 2, 3, 4, 5, 6, 7, 8, 9 or 10, etc., and the pressure drop of each microfluidic unit structure remains consistent or substantially consistent.

[0037] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, an external water phase separation tube 5, an oil phase separation tube 6, an internal water phase separation tube 7 and a collecting tube 8 are formed in the chip body, and an external water phase total inlet 1 connected to the external water phase separation tube 5, an oil phase total inlet 2 connected to the oil phase separation tube 6, an internal water phase total inlet 3 connected to the internal water phase separation tube 7 and a total outlet 4 connected to the collecting tube 8 are formed on the surface of the chip body.

[0038] The inlet of the external water phase flow channel of each microfluidic unit structure is respectively connected to the external water phase separation tube 5, the inlet of the oil phase flow channel is respectively connected to the oil phase separation tube 6, the inlet of the internal water phase flow channel is respectively connected to the internal water phase separation tube 7, and the inlet of the discharge flow channel is respectively connected to the collection tube 8.

[0039] In some embodiments of the present invention, a plurality of microfluidic unit structures are arranged in a single layer or multiple layers in a chip body.

[0040] like Figure 1 and Figure 2 As shown, the eight microfluidic unit structures are divided into two layers, namely an upper unit structure 9 and a lower unit structure 12, and four microfluidic unit structures in each unit structure layer are arranged in the chip body.

[0041] In some embodiments of the present invention, the flow channel widths of the water-in-oil microsphere forming part 10 and the water-in-oil-in-water microsphere forming part 11 are respectively 25 to 100 μm, for example, 25 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm or 100 μm.

[0042] The present application also discloses a chip preparation method, which is used to prepare the high-throughput double-emulsion microfluidic chip. Figure 3 As shown, the chip preparation method includes the following steps:

[0043] S1) Design a high-throughput double-emulsion microfluidic chip using 3D graphics software;

[0044] S2) using integrated 3D printing technology to prepare the designed high-throughput double-emulsion microfluidic chip;

[0045] S3) using a cleaning solution to clean excess resin material from the prepared high-throughput double-emulsion microfluidic chip;

[0046] S4) preparing a hydrophilic layer in each flow channel inside the high-throughput double-emulsion microfluidic chip;

[0047] S5) Connecting the high-throughput double-emulsion microfluidic chip to the interface.

[0048] The present invention adopts integrated 3D printing technology to prepare high-throughput double-emulsion microfluidic chip, which has the advantages of simple processing technology, low cost, and convenience for large-scale production; based on the integrated 3D printing technology, the chip structure design has a high degree of freedom, and complex high-integration chips can be prepared, thereby improving the ability to prepare high-throughput drug microspheres, especially for water-soluble drug microspheres. The high-throughput double-emulsion microfluidic chip prepared by the present invention using integrated 3D printing technology can efficiently, conveniently and ensure the quality of water-in-oil-in-water water-soluble drug microspheres.

[0049] In some embodiments of the present invention, 3D printing technology includes but is not limited to photo-stereolithography 3D printing technology, digital light processing 3D printing technology, etc.

[0050] In some embodiments of the present invention, the processing accuracy of integrated 3D printing is 2 to 10 μm, and fine and complex microfluidic chips can be prepared. For example, the accuracy can be 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm.

[0051] In some embodiments of the present invention, the substrate used for printing the high-throughput double-emulsion microfluidic chip can be made of acrylic resin material. The microfluidic chip prepared using this material has good mechanical properties, corrosion resistance, and is easy to observe.

[0052] In some embodiments of the present invention, the cleaning solution in step S3) includes but is not limited to fluorinated liquid, deionized water, etc.

[0053] In some embodiments of the present invention, the preparation of the hydrophilic layer in step S4) includes the following two methods:

[0054] Method 1: Piranha solution and potassium hydroxide / sodium hydroxide aqueous solution were used to treat the internal channels of the high-throughput double-emulsion microfluidic chip to form a hydrophilic layer.

[0055] Method 2: 5-10% of an emulsifier is added to the resin material of a 3D printed high-throughput double-emulsion microfluidic chip, and a hydrophilic microfluidic chip can be obtained after printing and cleaning, that is, a hydrophilic layer is obtained.

[0056] The hydrophilic layer prepared by the present invention has a lasting hydrophilic effect, so that the high-throughput double-emulsion microfluidic chip has good repeatability.

[0057] In some embodiments of the present invention, the connection method between the microfluidic chip and the interface in step S5) includes but is not limited to clamp connection or glue connection, and the glue includes but is not limited to acrylic glue, AB glue, etc.

[0058] The present application also discloses a method for preparing drug microspheres, which uses the high-throughput double-emulsion microfluidic chip or the high-throughput double-emulsion microfluidic chip prepared by the chip preparation method to prepare microspheres. Figure 3 As shown, the method for preparing drug microspheres comprises the following steps:

[0059] S6) preparing an inner water phase 13, an oil phase 14, and an outer water phase 15 solution;

[0060] S7) using a microfluidic pressure pump to inject the inner water phase 13, the oil phase 14, and the outer water phase 15 into the high-throughput double-emulsion microfluidic chip at a certain flow ratio to prepare water-in-oil-in-water drug microspheres;

[0061] S8) dispersing the drug microspheres into a receiving solution for solidification;

[0062] S9) washing the drug microspheres;

[0063] S10) freeze-drying the drug microspheres and storing them.

[0064] In some embodiments of the present invention, the components of the internal aqueous phase 13 include water-soluble drugs, protective agents, suspending agents and deionized water.

[0065] Furthermore, water-soluble drugs include but are not limited to leuprolide acetate, octreotide, exenatide, pasireotide, goserelin acetate, and the like.

[0066] Furthermore, the protective agent includes but is not limited to gelatin, mannitol, ammonium sulfate, etc., with a concentration of 0.1 to 10.0%.

[0067] For some drugs, protective agents have the advantages of improving drug stability, reducing activity loss, maintaining good sustained-release properties, and further increasing drug loading.

[0068] Furthermore, the suspending agent includes but is not limited to sodium alginate, gelatin, methyl cellulose, polyvinyl alcohol, etc., with a concentration of 0.1 to 10.0%.

[0069] The suspending agent can increase the viscosity of the inner aqueous phase 13 and prevent the drug from migrating to the outer phase, thereby further improving the encapsulation efficiency and drug loading of the drug microspheres.

[0070] In some embodiments of the present invention, the oil phase 14 includes a biocompatible, degradable polymer material and an oil phase solvent, and the concentration of the oil phase 14 solution is 1% w / v to 30% w / v.

[0071] Furthermore, the polymer material includes but is not limited to poly(lactic-co-glycolic acid) (PLGA), polylactic acid (PLA), and the like.

[0072] Furthermore, the oil phase solvent includes but is not limited to dichloromethane, ethyl acetate and the like.

[0073] In some embodiments of the present invention, the external aqueous phase 15 is a polyvinyl alcohol (PVA) solution with a concentration of 0.5-3% w / v.

[0074] In some embodiments of the present invention, the receiving solution is a PVA solution with a concentration of 0.5-3% w / v.

[0075] Furthermore, the solidification of the microspheres is accelerated by magnetic stirring at a rotation speed of 50 to 200 rpm.

[0076] Furthermore, the freeze-drying time of the drug microspheres is 24 to 72 hours.

[0077] The drug microspheres prepared by the drug microsphere preparation method of the present invention are of a core-shell structure, including an inner core and an outer shell, wherein the inner core contains a water-soluble drug, a protective agent, and a suspending agent, and the outer shell is a fat-soluble polymer material (polymer material) with biocompatibility and degradability. The drug microspheres have uniform and controllable particle sizes, high drug loading amounts, and high drug encapsulation rates.

[0078] The high-throughput double-emulsion microfluidic chip and the method for preparing drug microspheres in the present application will be further described below in conjunction with specific embodiments.

[0079] Example 1

[0080] Step S1, designing a high-throughput double-emulsion microfluidic chip using three-dimensional drawing software.

[0081] In this specific embodiment, an 8-channel double-emulsion microfluidic chip is designed. Figure 1 , Figure 2 As shown. The microfluidic chip has eight microfluidic unit structures integrated inside, with two layers, each layer having four microfluidic unit structures. Each microfluidic unit structure is a water-in-oil-in-water (W / O / W) template.

[0082] Step S2, using integrated 3D printing technology to prepare the designed high-throughput double-emulsion microfluidic chip.

[0083] In this specific embodiment, a high-throughput double-emulsion microfluidic chip is prepared by using a photocuring 3D printing device, the precision of the 3D printing device is 2μm, and the 3D printing material used is an acrylic photosensitive resin. Before printing the high-throughput double-emulsion microfluidic chip, the established microfluidic chip model is first sliced, and then the printing position and exposure parameters of the 3D printing device are adjusted to ensure that there is no collapse, pore blocking, etc. in the chip structure before officially starting printing.

[0084] Step S3, using a cleaning solution to clean excess resin material from the prepared high-throughput double-emulsion microfluidic chip.

[0085] Fluoride solution is sucked from a syringe to flush the resin material inside the flow channel, and then dried. Then, the microfluidic chip is placed under a UV curing lamp for curing.

[0086] Step S4, preparing a hydrophilic layer in each flow channel inside the high-throughput double-emulsion microfluidic chip.

[0087] Measure concentrated sulfuric acid and hydrogen peroxide solution, prepare piranha solution in an ice water bath, inject the prepared piranha solution into the flow channel of the microfluidic chip, let it stand, and then rinse the flow channel with pure water. Prepare sodium hydroxide solution, inject the prepared sodium hydroxide solution into the flow channel of the microfluidic chip, let it stand, and then rinse the flow channel with pure water.

[0088] Step S5, connecting the high-throughput double-emulsion microfluidic chip to the interface.

[0089] The inner water phase inlet, oil phase inlet, outer water phase inlet and outlet on the microfluidic chip were bonded to the PEEK flat joint using acrylic glue and cured at room temperature for 24 hours. Each inlet of the microfluidic chip was connected to a microfluidic pressure pump using a Teflon tube, and the outlet was inserted into a receiving container.

[0090] Step S6, preparing inner water phase, oil phase and outer water phase solutions.

[0091] In this specific embodiment, PLGA drug microspheres are prepared using the water-soluble drug leuprolide acetate. Gelatin and leuprolide acetate are dissolved in deionized water to prepare an inner aqueous phase. PLGA is dissolved in ethyl acetate to prepare an oil phase. The outer aqueous phase is a PVA solution with a concentration of 1% w / v. Finally, the prepared aqueous phase and oil phase are filtered using a microporous filter membrane.

[0092] Step S7, using a microfluidic pressure pump to inject the inner water phase, the oil phase, and the outer water phase into the high-throughput double-emulsion microfluidic chip at a certain flow ratio to prepare water-in-oil-in-water drug microspheres.

[0093] Through the extrusion / shearing action of the three solutions at the intersection of the chip, dispersed PLGA-leuprorelin microspheres can be obtained. The formation process is as follows Figure 4 shown.

[0094] Step S8, dispersing the drug microspheres into a receiving liquid for solidification.

[0095] PLGA-leuprorelin was dispersed in 1% w / v PVA solution. During the dispersion process, magnetic stirring was used to accelerate the solidification of drug microspheres.

[0096] Step S9, cleaning the solidified drug microspheres.

[0097] The receiving solution was filtered out using a suction filtration device, and the PVA and unencapsulated drugs on the surface of the PLGA-leuprorelin microspheres were rinsed with deionized water.

[0098] Step S10, freeze-drying the drug microspheres and storing them.

[0099] The PLGA-leuprorelin microspheres were placed in a freeze dryer and dried for 48 hours. Finally, the PLGA-leuprorelin microspheres were stored at 2-8° C. in the dark.

[0100] The PLGA-leuprolide microspheres finally obtained in this example are of a core-shell structure, wherein the core contains leuprolide acetate 17 drug and gelatin 16, and the shell is a biocompatible and degradable PLGA 18 material. Figure 5 The particle size of the prepared PLGA-leuprorelin microspheres is about 32 μm, the CV value is 4.5%, and the optical microscope image and particle size distribution are shown in Figure 6 shown.

[0101] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A high-throughput double-emulsion microfluidic chip, characterized in that: include: A chip body, wherein a plurality of microfluidic unit structures are integrated inside the chip body, and each of the microfluidic unit structures is a water-in-oil-in-water template; Each of the microfluidic unit structures includes an external water phase flow channel, an oil phase flow channel, an internal water phase flow channel and a discharge flow channel. The oil phase flow channel and the internal water phase flow channel intersect to form an oil-in-water microsphere formation location and extend to form an oil-in-water microsphere flow channel. The external water phase flow channel and the oil-in-water microsphere flow channel intersect to form a water-in-oil-in-water microsphere formation location, and the discharge flow channel is connected to the water-in-oil-in-water microsphere formation location.

2. The high-throughput double-emulsion microfluidic chip according to claim 1, characterized in that: The chip body is formed with an external water phase liquid separation tube, an oil phase liquid separation tube, an internal water phase liquid separation tube and a liquid collection tube, and the surface of the chip body is formed with an external water phase total inlet connected to the external water phase liquid separation tube, an oil phase total inlet connected to the oil phase liquid separation tube, an internal water phase total inlet connected to the internal water phase liquid separation tube and a total outlet connected to the liquid collection tube; The inlet of the external water phase flow channel of each microfluidic unit structure is respectively connected to the external water phase liquid separation tube, the inlet of the oil phase flow channel is respectively connected to the oil phase liquid separation tube, the inlet of the internal water phase flow channel is respectively connected to the internal water phase liquid separation tube, and the inlet of the discharge flow channel is respectively connected to the collecting pipe.

3. The high-throughput double-emulsion microfluidic chip according to claim 1, characterized in that: A plurality of the microfluidic unit structures are arranged in a single layer or multiple layers in the chip body.

4. The high-throughput double-emulsion microfluidic chip according to claim 1, characterized in that: The flow channel widths at the water-in-oil microsphere formation location and the water-in-oil-in-water microsphere formation location are 25 to 100 μm, respectively.

5. A method for preparing a high-throughput double-emulsion microfluidic chip according to any one of claims 1 to 4, characterized in that: The following steps are involved: Design high-throughput double-emulsion microfluidic chips using 3D graphics software; The designed high-throughput double-emulsion microfluidic chip was prepared using integrated 3D printing technology; Using a cleaning solution to clean excess resin material from the prepared high-throughput double-emulsion microfluidic chip; A hydrophilic layer is prepared in each flow channel inside a high-throughput double-emulsion microfluidic chip; Connect the high-throughput double-emulsion microfluidic chip to the interface.

6. The chip preparation method according to claim 5, characterized in that: The processing accuracy of the integrated 3D printing is 2 to 10 μm.

7. The chip preparation method according to claim 5, characterized in that: The preparation of the hydrophilic layer comprises: The flow channels inside the high-throughput double-emulsion microfluidic chip are treated with piranha solution and potassium hydroxide / sodium hydroxide aqueous solution to form a hydrophilic layer; or 5-10% of emulsifier is added to the resin material of the 3D printed high-throughput double-emulsion microfluidic chip, and a hydrophilic layer is obtained after printing and washing.

8. A method for preparing drug microspheres, using the high-throughput double-emulsion microfluidic chip as described in any one of claims 1 to 4 or the high-throughput double-emulsion microfluidic chip prepared by the chip preparation method as described in any one of claims 5 to 7 to prepare microspheres, characterized in that: The following steps are involved: Prepare inner water phase, oil phase and outer water phase solution; Using a microfluidic pressure pump, an inner water phase, an oil phase, and an outer water phase are injected into a high-throughput double-emulsion microfluidic chip at a certain flow ratio to prepare water-in-oil-in-water drug microspheres; Dispersing the drug microspheres into a receiving solution for solidification; Cleaning the solidified drug microspheres; The drug microspheres are freeze-dried and stored.

9. The method for preparing drug microspheres according to claim 8, characterized in that: The components of the inner water phase include water-soluble drugs, protective agents, suspending agents and deionized water.

10. The method for preparing drug microspheres according to claim 8, characterized in that: The oil phase comprises biocompatible, degradable polymer materials and an oil phase solvent; the external water phase is a polyvinyl alcohol solution.

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