Synthesis of water-soluble system polymer bio-ink and preparation method and application thereof

Abstract

This invention provides a water-soluble synthetic polymer bio-ink, comprising a dispersed phase and a dispersant mixed together. The dispersant is water, and the dispersed phase includes polymer microspheres, a crosslinking agent, and a UV photoinitiator. The polymer microspheres are made of a synthetic polymer material modified with double bonds at both ends. This water-soluble synthetic polymer bio-ink can be used for 3D bioprinting in a water-soluble system. This invention also provides a method for preparing the water-soluble synthetic polymer bio-ink, which is simple, low-cost, and suitable for industrial production. Furthermore, this invention provides an application of the water-soluble synthetic polymer bio-ink, which allows for 3D bioprinting and solidification in a water-soluble system to obtain a structurally stable and well-formed 3D printed scaffold. Cell fluid can also be added to the water-soluble synthetic polymer bio-ink to print a cell-containing 3D printed scaffold.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, specifically to a water-soluble synthetic polymer bio-ink, its preparation method, and its application. Background Technology

[0002] 3D bioprinting generally refers to 3D bioprinting technology. 3D bioprinting is a new technological means that uses computer three-dimensional models as "blueprints" and assembles them with special "bio-inks" to ultimately manufacture artificial organs and biomedical products. Due to its characteristics of high precision, high efficiency and personalized manufacturing, 3D bioprinting has attracted enough attention in the field of biomedicine and has a very broad application prospect.

[0003] Because synthetic polymer materials, including polycaprolactone (PCL), polylactic acid (PLA), and polylactic acid glycolic acid copolymer (PLGA), have low physiological toxicity and are biodegradable and biocompatible, bio-inks based on synthetic polymer materials have excellent printing and mechanical properties and have been widely used in tissue engineering research.

[0004] Traditional methods for using synthetic polymers in 3D bioprinting employ either high-temperature melt printing or solvent-based printing. High-temperature melt printing involves heating the polymer to dissolve it and then cooling it to achieve the desired shape. Solvent-based printing uses organic solvents to dissolve the polymer and then freezes it to achieve the desired shape. Neither of these methods is gentle and cannot be used for cell-borne 3D bioprinting. High-temperature melt printing requires a prolonged heating process, which can easily lead to uncontrollable material degradation. The resulting scaffold lines have dense surfaces that are prone to collapse, low porosity, and poor scaffold formation. Solvent-based printing requires the use of organic solvents, which can leave residual organic solvents inside the printed scaffold, and the resulting scaffold is also prone to collapse and has poor formation. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the first objective of the present invention is to provide a water-soluble synthetic polymer bio-ink, which has the advantages of good biocompatibility and can be printed in a water-soluble system.

[0006] The second objective of this invention is to provide a method for preparing a water-soluble synthetic polymer bio-ink, which is simple in process, low in cost, and easy to industrialize.

[0007] The third objective of this invention is to provide an application of a water-soluble synthetic polymer bio-ink, which is used for 3D bioprinting to obtain a structurally stable and well-formed 3D printed scaffold. Furthermore, cell fluid can be added to the water-soluble synthetic polymer bio-ink to print a cell-containing 3D printed scaffold.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A water-soluble synthetic polymer bio-ink comprises a dispersed phase and a dispersant mixed together, wherein the dispersant is water, and the dispersed phase includes polymer microspheres, a crosslinking agent, and a UV photoinitiator, wherein the polymer microspheres are made of a synthetic polymer material modified with double bonds at both ends; wherein,

[0010] The polymer microspheres have a mass percentage of 10% to 50% relative to the dispersant;

[0011] The crosslinking agent has a mass percentage of 3% to 20% relative to the dispersant;

[0012] The mass percentage of the ultraviolet photoinitiator relative to the dispersant is 0.1% to 0.5%.

[0013] Preferably, in the synthetic polymer material with double bond modification at both ends, the number of introduced double bonds is at least two, and the double bonds include at least carbon-carbon double bonds; the synthetic polymer material is selected from at least one of polycaprolactone, polylactic acid, polylactic acid-glycolic acid copolymer and polyhydroxy fatty acid.

[0014] Preferably, the crosslinking agent is selected from at least one of sodium methacrylamide, methacrylamide hyaluronic acid, F127, chitosan, polyvinyl alcohol modified with double bonds, gellan gum modified with double bonds, and carbomer modified with double bonds; wherein the double bond modification method of the polyvinyl alcohol modified with double bonds, the gellan gum modified with double bonds, and the carbomer modified with double bonds is end-to-end modification, and the number of double bonds introduced is at least two, wherein the double bonds include at least carbon-carbon double bonds.

[0015] Preferably, the ultraviolet photoinitiator is selected from at least one of LAP, photoinitiator 2959, photoinitiator 1173, and TPO.

[0016] This invention also provides a method for preparing a water-soluble synthetic polymer bio-ink, comprising the following steps:

[0017] S1. Preparation of synthetic polymer materials with double bonds at both ends;

[0018] S2. The synthetic polymer material with double bonds modified at both ends is used to synthesize polymer microspheres;

[0019] S3. The polymer microspheres, the crosslinking agent, and the ultraviolet photoinitiator are dispersed and mixed with the dispersant in a predetermined mass ratio to obtain the synthetic polymer bio-ink of the water-soluble system.

[0020] Preferably, step S1 includes:

[0021] S11. After mixing and reacting the synthetic polymer solution, triethylamine and acryloyl chloride solution, filter the mixture and collect the filtrate to precipitate the synthetic polymer material with double bond modification at the hydroxyl end.

[0022] S12. Prepare a synthetic polymer solution with double bond modification at the hydroxyl end. Mix the synthetic polymer solution with double bond modification at the hydroxyl end, 1-ethyl-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide and acrylamide and react them. Mix the mixed liquid after the reaction with deionized water and separate the liquid to obtain a synthetic polymer with double bond modification at both ends.

[0023] More preferably, in step S11, the molar ratio of the synthetic polymer material to the triethylamine is 1:(2-5), and the molar ratio of the triethylamine to the acryloyl chloride is 1:(1-3).

[0024] The molar ratio of the synthetic polymer to the 1-ethyl-(3-dimethylaminopropyl)carbodiimide is 1:(2-5), the molar ratio of the 1-ethyl-(3-dimethylaminopropyl)carbodiimide to the N-hydroxysuccinimide is 1:(1-2), and the molar ratio of the synthetic polymer to acrylamide is 1:(2-5).

[0025] Preferably, in step S2, the method for synthesizing polymer microspheres from synthetic polymer materials with double bond modifications at both ends is selected from one of the following: emulsion method, membrane emulsification method, nanoprecipitation method, microfluidic technology, and supercritical fluid technology.

[0026] The present invention also provides an application of a water-soluble synthetic polymer bio-ink, comprising the following steps: 3D bioprinting of the water-soluble synthetic polymer bio-ink and solidification to obtain a 3D printed scaffold.

[0027] Preferably, the synthetic polymer bio-ink of the water-soluble system also contains cell fluid, which is used to print a 3D printed scaffold containing cells.

[0028] The beneficial effects of this invention are as follows:

[0029] 1. The raw materials for the water-soluble synthetic polymer bio-ink provided by this invention are all water-soluble polymer microspheres, crosslinking agents, ultraviolet photoinitiators, and dispersants, which can be used for 3D bioprinting in a water-soluble system under mild conditions. Therefore, the water-soluble synthetic polymer bio-ink provided by this invention can be directly used for 3D bioprinting and solidification in a water-soluble system to obtain a 3D printed scaffold; adding cell fluid to the water-soluble synthetic polymer bio-ink for 3D bioprinting and solidification yields a cell-containing 3D printed scaffold, thus improving the biocompatibility of the 3D printed scaffold.

[0030] 2. The water-soluble synthetic polymer bio-ink provided by the present invention can change the viscosity of the water-soluble synthetic polymer bio-ink by adjusting the mass percentage of the crosslinking agent relative to the dispersant to 3% to 20%, and can maintain the stability of the 3D printed scaffold obtained when using the water-soluble synthetic polymer bio-ink for 3D bioprinting by adjusting the mass percentage of the polymer microspheres relative to the dispersant to 3% to 20%, thereby obtaining a structurally stable and well-formed 3D printed scaffold.

[0031] 3. The crosslinking agent used in the water-soluble synthetic polymer bio-ink provided by this invention is a macromolecule with good biocompatibility and good gelation effect. When using the water-soluble synthetic polymer bio-ink for 3D bioprinting, the obtained 3D printed scaffold has low toxicity and good cell compatibility. While providing the environment required for cell growth, it also promotes cell adhesion, growth and proliferation.

[0032] 4. The crosslinking agent used in the water-soluble synthetic polymer bio-ink provided by this invention enables the water-soluble synthetic polymer bio-ink to have a pre-shape before ultraviolet crosslinking, allowing for pre-printing and post-curing, enabling batch printing and improving the efficiency of 3D bioprinting.

[0033] 5. The preparation method of the water-soluble system synthetic polymer bio-ink provided by the present invention has a simple preparation process, low cost, and is very conducive to industrial production.

[0034] 6. The water-soluble synthetic polymer bio-ink provided by this invention can change the surface micromorphology of 3D printed scaffolds by altering the size of polymer microspheres, selectively influencing cell adhesion, migration, proliferation and other behaviors. Attached Figure Description

[0035] Figure 1 This is a process flow diagram of a method for preparing a water-soluble synthetic polymer bio-ink according to an embodiment of the present invention;

[0036] Figure 2This is a schematic diagram of a 3D printed scaffold structure obtained by 3D bioprinting using the synthetic polymer bio-ink with a water-soluble system according to an embodiment of the present invention.

[0037] Figure 3 This is the 1H NMR spectrum of the polylactic acid-glycolic acid copolymer with double bond modification at both ends obtained in Example 1 of the present invention.

[0038] Figure 4 These are SEM scan results of polylactic acid glycolic acid copolymer microspheres with different particle size distributions obtained in Example 1 of this invention;

[0039] Figure 5 This is a SEM scan result of a 3D printed scaffold obtained when bio-ink formulated with polylactic acid glycolic acid copolymer microspheres of different particle size distributions obtained in Example 1 of the present invention is used for 3D bioprinting. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Examples of these preferred embodiments are illustrated in the drawings. The embodiments of the present invention shown in and described with reference to the drawings are merely exemplary, and the present invention is not limited to these embodiments.

[0041] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0042] The inventors of this invention address the problems in existing technologies where traditional synthetic polymer materials are used for 3D bioprinting via high-temperature melting or solvent methods. These problems include the inability to achieve cell-carrying printing and the resulting 3D printed scaffolds being prone to collapse, exhibiting poor molding, and potentially leaving organic solvent residues. The first objective of this invention is to provide a water-soluble synthetic polymer bio-ink with good biocompatibility and the advantage of being printable in a water-soluble system. The second objective is to provide a method for preparing this water-soluble synthetic polymer bio-ink, which is simple, low-cost, and suitable for industrial production. The third objective is to provide an application of this water-soluble synthetic polymer bio-ink, enabling 3D bioprinting to obtain structurally stable and well-formed 3D printed scaffolds. Furthermore, cell fluid can be added to the water-soluble synthetic polymer bio-ink to print cell-containing 3D printed scaffolds.

[0043] This invention provides a water-soluble synthetic polymer bio-ink, comprising a dispersed phase and a dispersant mixed together, wherein the dispersant is water, and the dispersed phase comprises polymer microspheres, a crosslinking agent, and a UV photoinitiator, wherein the polymer microspheres are made of a synthetic polymer material modified with double bonds at both ends; wherein,

[0044] The polymer microspheres have a mass percentage of 10% to 50% relative to the dispersant. When the mass percentage of the polymer microspheres relative to the dispersant is in the range of 10% to 50%, the stability of the 3D printed scaffold can be maintained when using water-soluble synthetic polymer bio-ink for 3D bioprinting, resulting in a structurally stable and well-formed 3D printed scaffold. For example, the mass percentage can be 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50%.

[0045] The crosslinking agent has a mass percentage of 3% to 20% relative to the dispersant. When the mass percentage of the crosslinking agent relative to the dispersant is in the range of 3% to 20%, it can give the water-soluble synthetic polymer bioink different viscosities, affecting the adhesion, growth, and proliferation behavior of cells on the 3D printed scaffold when the water-soluble synthetic polymer bioink is applied. The mass percentage of the crosslinking agent relative to the dispersant can be, for example, 3%, 5%, 7%, 9%, 11%, 13%, 15%, 17%, 19%, or 20%.

[0046] The mass percentage of the ultraviolet photoinitiator relative to the dispersant is 0.1% to 0.5%, for example, it can be 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, or 0.5%.

[0047] Specifically, in the synthetic polymer material modified with double bonds at both ends, the number of introduced double bonds is at least two, and the double bonds include at least carbon-carbon double bonds; the synthetic polymer material is selected from at least one of polycaprolactone (PCL), polylactic acid (PLA), polylactic-co-glycolic acid copolymer (PLGA), and polyhydroxyalkanoates (PHA). It should be noted that the type and molecular weight of the synthetic polymer material are highly selective and can be chosen according to the application requirements. In a preferred embodiment of the present invention, polylactic-co-glycolic acid copolymer (PLGA) with a molecular weight of 100,000 is selected.

[0048] Specifically, the crosslinking agent is selected from at least one of sodium methacrylamide alginate, methacrylamide hyaluronic acid, F127, chitosan, polyvinyl alcohol modified with double bonds, gellan gum modified with double bonds, and carbomer modified with double bonds; the double bond modification method of the polyvinyl alcohol modified with double bonds, the gellan gum modified with double bonds, and the carbomer modified with double bonds is end-to-end modification, the number of introduced double bonds is at least two, and the double bonds include at least carbon-carbon double bonds.

[0049] It is worth mentioning that the crosslinking agent is a large molecule with good biocompatibility and good gelation effect. When using the synthetic polymer bio-ink with this water-soluble system for 3D bioprinting, the resulting 3D printed scaffold has low toxicity and good cell compatibility. While providing the environment required for cell growth, it also promotes cell adhesion, growth and proliferation.

[0050] In addition, the crosslinking agent used in the water-soluble synthetic polymer bio-ink provided by the present invention enables the water-soluble synthetic polymer bio-ink to have a pre-shape before ultraviolet crosslinking, allowing for pre-printing and post-curing, enabling batch printing and improving the efficiency of 3D bioprinting.

[0051] Specifically, the ultraviolet photoinitiator is selected from at least one of LAP, photoinitiator 2959, photoinitiator 1173, and TPO.

[0052] This invention also provides a method for preparing a water-soluble synthetic polymer bio-ink, such as... Figure 1 As shown, Figure 1 This is a process flow diagram of a method for preparing a water-soluble synthetic polymer bio-ink provided by the present invention, including the following steps:

[0053] S1. Preparation of synthetic polymer materials with double bonds at both ends;

[0054] S2. The synthetic polymer material with double bonds modified at both ends is used to synthesize polymer microspheres;

[0055] S3. The polymer microspheres, the crosslinking agent, and the ultraviolet photoinitiator are dispersed and mixed with the dispersant in a predetermined mass ratio to obtain the synthetic polymer bio-ink of the water-soluble system.

[0056] Specifically, step S1 includes:

[0057] S11. After mixing and reacting the synthetic polymer solution, triethylamine and acryloyl chloride solution, filter the mixture and collect the filtrate to precipitate the synthetic polymer material with double bond modification at the hydroxyl end.

[0058] S12. Prepare a synthetic polymer solution with double bond modification at the hydroxyl end. Mix the synthetic polymer solution with double bond modification at the hydroxyl end, 1-ethyl-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide and acrylamide and react them. Mix the mixed liquid after the reaction with deionized water and separate the liquid to obtain a synthetic polymer with double bond modification at both ends.

[0059] More specifically, the solvent in the synthetic polymer solution, the acryloyl chloride solution, and the synthetic polymer solution with double bonds modified at the hydroxyl end is selected from at least one of dichloromethane, chloroform, and acetone. In a preferred embodiment of the present invention, dichloromethane is preferred.

[0060] More specifically, in step S11, the molar ratio of the synthetic polymer material to the triethylamine is 1:(2-5), for example, it can be 1:2, 1:3, 1:4 or 1:5.

[0061] The molar ratio of triethylamine to acryloyl chloride is 1:(1-3), for example, it can be 1:1, 1:1.5, 1:2, 1:2.5 or 1:3.

[0062] The molar ratio of the synthetic polymer to the 1-ethyl-(3-dimethylaminopropyl)carbodiimide is 1:(2-5), for example, it can be 1:2, 1:3, 1:4 or 1:5.

[0063] The molar ratio of 1-ethyl-(3-dimethylaminopropyl)carbodiimide to N-hydroxysuccinimide is 1:(1-2), for example, it can be 1:1, 1:1.2, 1:1.4, 1:1.6, 1:1.8 or 1:2.

[0064] The molar ratio of the synthetic polymer to acrylamide is 1:(2-5), for example, it can be 1:2, 1:3, 1:4 or 1:5.

[0065] In addition, in order to obtain synthetic polymer materials with double bond modification at both ends with higher purity, in a preferred embodiment of the present invention, step S1 further includes vacuum drying of the synthetic polymer material with double bond modification at the hydroxyl end obtained in step S11, and step S12 involves at least three liquid-liquid separation operations, and rotary evaporation and vacuum drying of the obtained synthetic polymer material with double bond modification at both ends.

[0066] More specifically, in step S2, the method for synthesizing polymer microspheres from synthetic polymer materials with double bond modifications at both ends is selected from one of the following: emulsion method, membrane emulsification method, nanoprecipitation method, microfluidic technology, and supercritical fluid technology.

[0067] In addition, in a preferred embodiment of the present invention, the polymer microspheres obtained in step S2 are further sorted through sieves with specifications of 40μm, 70μm and 100μm to separate polymer microspheres with different particle size distributions of 0μm~40μm, 40μm~70μm and 70μm~100μm.

[0068] This invention also provides an application of a water-soluble synthetic polymer bio-ink, comprising the following steps: 3D bioprinting the water-soluble synthetic polymer bio-ink and solidifying it to obtain a 3D printed scaffold. For example... Figure 2 As shown, Figure 2 This is a schematic diagram of a 3D printed scaffold structure obtained by 3D bioprinting using the synthetic polymer bio-ink of the water-soluble system of this invention.

[0069] It is worth mentioning that the raw materials of the water-soluble bio-ink of polymer microspheres provided by this invention are all water-soluble polymer microspheres, crosslinking agents, ultraviolet photoinitiators, and dispersants, which can be used for 3D bioprinting in a water-soluble system under mild conditions. Therefore, the synthetic polymer bio-ink of the water-soluble system provided by this invention can be directly used for 3D bioprinting and solidification in a water-soluble system to obtain a 3D printed scaffold; alternatively, cell fluid can be added to the synthetic polymer bio-ink of the water-soluble system, and then 3D bioprinting and solidification can be performed in a water-soluble system to obtain a cell-containing 3D printed scaffold, thus improving the biocompatibility of the 3D printed scaffold.

[0070] Specifically, the cell types and densities in the cell sap are not limited.

[0071] Specifically, the curing method is selected from one of ultraviolet light curing, thermal initiation curing, and click chemical curing.

[0072] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, provides a synthetic polymeric bio-ink system based on the present invention, its preparation method, and its application. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0073] Example 1

[0074] A water-soluble synthetic polymer bio-ink comprises a dispersed phase and a dispersant mixed together, wherein the dispersant is 1 mL of water, and the dispersed phase comprises 300 mg of polylactic acid glycolic acid copolymer microspheres, 70 mg of sodium methacrylate, and 2.5 mg of LAP.

[0075] A method for preparing a water-soluble synthetic polymer bio-ink includes the following steps:

[0076] S1. Preparation of polylactic acid-glycolic acid copolymer with double bonds modified at both ends (Mn = 100000)

[0077] At room temperature, 20 μL of acryloyl chloride was dissolved in 20 mL of dichloromethane to prepare an acryloyl chloride solution;

[0078] At room temperature, 10g of polylactic acid glycolic acid copolymer was added to a three-necked flask, followed by 200mL of dichloromethane. The mixture was stirred until homogeneous to obtain a polylactic acid glycolic acid copolymer solution.

[0079] Under ice-water bath conditions, slowly add 35 μL of triethylamine to the three-necked flask, then add the pre-prepared acryloyl chloride solution dropwise, keeping the system temperature at zero degrees Celsius, until all the acryloyl chloride solution has been added.

[0080] The three-necked flask containing the added acryloyl chloride solution was reacted for 24 hours at room temperature and under nitrogen protection.

[0081] After the reaction was completed, the system was filtered, the filtrate was collected and precipitated with 200 mL of anhydrous diethyl ether to obtain the crude product. The crude product was then vacuum dried for 1 day to obtain a high-purity polylactic acid-glycolic acid copolymer with double bond modification at the hydroxyl end.

[0082] 10g of the polylactic-co-glycolic acid copolymer with double-bond modification at the hydroxyl ends was dissolved in 200mL of dichloromethane. 34.5mg of 1-ethyl-(3-dimethylaminopropyl)carbodiimide was slowly added, and the mixture was stirred at room temperature for 2 hours. Then, 57.5mg of N-hydroxysuccinimide and 14.2mg of acrylamide were slowly added, and the reaction was continued at room temperature for 24 hours. After the reaction was complete, the resulting liquid mixture was mixed with an equal volume of deionized water. The organic phase was collected after the liquid separated into layers. This process was repeated three times. The crude product was then subjected to rotary evaporation and vacuum drying for 1 day to obtain a high-purity polylactic-co-glycolic acid copolymer with double-bond modification at both ends. Figure 3 As shown, Figure 3 This is the 1H NMR spectrum of the polylactic acid glycolic acid copolymer with a molecular weight of 100,000 and double bond modification at both ends obtained in Example 1 of the present invention; as can be seen from the figure, carbon-carbon double bonds were successfully grafted onto both ends of the polylactic acid glycolic acid copolymer.

[0083] S2. Synthesize polymer microspheres from the synthetic polymer material with double bonds modified at both ends.

[0084] 1g of the polylactic acid-glycolic acid copolymer with double bonds at both ends obtained in step S1 was dissolved in 20mL of dichloromethane to prepare a polylactic acid-glycolic acid copolymer solution with double bonds at both ends. Then, 2g of polyvinyl alcohol was placed in a beaker, and 200mL of deionized water was added to dissolve it. The mixture was stirred evenly at room temperature to obtain a polyvinyl alcohol solution.

[0085] Under magnetic stirring, a solution of polylactic acid-glycolic acid copolymer with double bonds at both ends was slowly added to a polyvinyl alcohol solution using a syringe. The dropping rate was controlled at 0.5 mL / min until all the polylactic acid-glycolic acid copolymer solution with double bonds at both ends was added. The mixture was then stirred at room temperature for 24 hours. Polyvinyl alcohol effectively dispersed the polylactic acid-glycolic acid copolymer microspheres formed during the reaction. After the reaction, the solid phase was collected by static precipitation, centrifugation, and redispersed with deionized water. This process was repeated eight times to obtain crude polylactic acid-glycolic acid copolymer microspheres. The crude polylactic acid-glycolic acid copolymer microspheres were then passed through sieves with sizes of 40 μm, 70 μm, and 100 μm to separate crude polylactic acid-glycolic acid copolymer microspheres with different particle size distributions: 0 μm–40 μm, 40 μm–70 μm, and 70 μm–100 μm.

[0086] The crude polylactic acid-glycolic acid copolymer microspheres with different particle size distributions of 0μm~40μm, 40μm~70μm, and 70μm~100μm obtained above were vacuum dried for 1 day to obtain polylactic acid-glycolic acid copolymer microspheres with different particle size distributions of 0μm~40μm, 40μm~70μm, and 70μm~100μm. For example... Figure 4 As shown, Figure 4 This is a SEM scan result of polylactic acid-glycolic acid copolymer microspheres with different particle size distributions of 0μm~40μm, 40μm~70μm and 70μm~100μm obtained in Example 1 of the present invention.

[0087] S3. Preparation of a water-soluble synthetic polymer bio-ink system

[0088] 300 mg of polylactic acid glycolic acid copolymer microspheres with different particle size distributions of 0 μm to 40 μm, 40 μm to 70 μm and 70 μm to 100 μm obtained in step S2, 70 mg of sodium methacryloyl alginate, 2.5 mg of LAP and 1 mL of water were mixed evenly at room temperature to obtain a water-soluble synthetic polymer bio-ink.

[0089] The application of a water-soluble synthetic polymer bio-ink includes the following steps:

[0090] The synthetic polymer bio-ink from the above water-soluble system was used for 3D bioprinting in the water-soluble system, and then cured in a UV crosslinking instrument to obtain a 3D printed scaffold. For example... Figure 5 As shown, Figure 5This is a SEM scan image of a 3D-printed scaffold obtained during 3D bioprinting using bio-ink formulated with polylactic-co-glycolic acid copolymer microspheres of different particle size distributions (0μm–40μm, 40μm–70μm, and 70μm–100μm). It can be seen that the 3D-printed scaffolds obtained by 3D bioprinting using bio-ink formulated with polylactic-co-glycolic acid copolymer microspheres of different particle sizes have different morphologies and roughnesses.

[0091] The cell suspension was seeded onto the 3D printed scaffold obtained above. The 3D printed scaffold seeded with cell suspension was then fixed, dehydrated, and lyophilized. The results were observed by scanning electron microscopy. The results showed that when sodium methacrylate was used as a crosslinking agent, the 3D printed scaffolds with the highest number of adherent cells and the best spreading morphology were obtained by using bio-ink formulated with polylactic acid glycolic acid copolymer microspheres with a particle size of 70μm to 100μm.

[0092] Example 2

[0093] A water-soluble synthetic polymer bio-ink comprises a dispersed phase and a dispersant mixed together, wherein the dispersant is 1 mL of water, and the dispersed phase comprises 200 mg of polylactic acid glycolic acid copolymer microspheres, 50 mg of methacryloyl hyaluronic acid, and 2 mg of LAP.

[0094] A method for preparing a water-soluble synthetic polymer bio-ink includes the following steps:

[0095] Steps S1 and S2 are the same as in Example 1.

[0096] S3. Preparation of a water-soluble synthetic polymer bio-ink system

[0097] 200 mg of polylactic acid-glycolic acid copolymer microspheres with different particle size distributions of 0 μm to 40 μm, 40 μm to 70 μm and 70 μm to 100 μm obtained in step S2, 50 mg of methacryloyl hyaluronic acid, 2 mg of LAP and 1 mL of water were mixed evenly at room temperature to obtain a water-soluble synthetic polymer bio-ink.

[0098] The application of a water-soluble synthetic polymer bio-ink includes the same steps as in Example 1. The observation results show that when methacrylamide hyaluronic acid is used as a crosslinking agent, the bio-ink formulated with polylactic acid glycolic acid copolymer microspheres with a particle size of 70μm to 100μm is used for 3D bioprinting, resulting in the highest number of adhered cells and the best spreading morphology on the 3D printed scaffold.

[0099] Example 3

[0100] A water-soluble synthetic polymer bio-ink comprises a dispersed phase and a dispersant mixed together, wherein the dispersant is 1 mL of water, and the dispersed phase comprises 100 mg of polylactic acid glycolic acid copolymer microspheres, 50 mg of sodium methacrylate, and 2 mg of LAP.

[0101] A method for preparing a water-soluble synthetic polymer bio-ink includes the following steps:

[0102] Steps S1 and S2 are the same as in Example 1.

[0103] S3. Preparation of a water-soluble synthetic polymer bio-ink system

[0104] 100 mg of polylactic acid-glycolic acid copolymer microspheres with different particle size distributions (0 μm–40 μm, 40 μm–70 μm, and 70 μm–100 μm) obtained in step S2, 50 mg of sodium methacryloyl alginate, 2 mg of LAP, and 1 mL of water were mixed evenly at room temperature to obtain a water-soluble synthetic polymer bioink. Then, 100 μL of cell suspension was added and mixed thoroughly.

[0105] The application of a water-soluble synthetic polymer bio-ink includes the following steps:

[0106] 100 μL of cell suspension was added to the above-mentioned water-soluble system of synthetic polymer bio-ink, and then 3D bioprinting was performed in the water-soluble system. The 3D printed scaffold containing cells was cured in an ultraviolet crosslinker.

[0107] After fixing, dehydrating, and lyophilizing the above-mentioned cell-containing 3D printed scaffolds, the results were observed by scanning electron microscopy. The results showed that when sodium methacrylamide alginate was used as a crosslinking agent, the 3D printed scaffolds with the highest number of adhered cells and the best spreading morphology were obtained by using bio-ink formulated with polylactic acid glycolic acid copolymer microspheres with a particle size of 70μm to 100μm for 3D bioprinting.

[0108] Example 4

[0109] A water-soluble synthetic polymer bio-ink comprises a dispersed phase and a dispersant mixed together, wherein the dispersant is 1 mL of water, and the dispersed phase comprises 110 mg of polylactic acid glycolic acid copolymer microspheres, 40 mg of methacryloyl hyaluronic acid, and 1 mg of LAP.

[0110] A method for preparing a water-soluble synthetic polymer bio-ink includes the following steps:

[0111] Steps S1 and S2 are the same as in Example 1.

[0112] S3. Preparation of a water-soluble synthetic polymer bio-ink system

[0113] 100 mg of polylactic acid-glycolic acid copolymer microspheres with different particle size distributions of 0 μm to 40 μm, 40 μm to 70 μm and 70 μm to 100 μm obtained in step S2, 40 mg of methacrylamide hyaluronic acid, 1 mg of LAP and 1 mL of water were mixed evenly at room temperature to obtain a water-soluble synthetic polymer bio-ink.

[0114] The application of a water-soluble synthetic polymer bio-ink includes the same steps as in Example 3. The observation results are as follows: when methacrylamide hyaluronic acid is used as a crosslinking agent, the bio-ink prepared with polylactic acid glycolic acid copolymer microspheres with a particle size of 70μm to 100μm is used for 3D bioprinting, resulting in the highest number of adhered cells and the best spreading morphology in the 3D printed scaffold.

[0115] The above description is only a specific embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for preparing a water-soluble synthetic polymer bio-ink, characterized in that, The synthetic polymer bio-ink comprises a mixture of a dispersion phase and a dispersant, wherein the dispersant is water, and the dispersion phase comprises polymer microspheres, a crosslinking agent, and a UV photoinitiator; wherein the polymer microspheres account for 10% to 50% of the mass percentage of the dispersant; the crosslinking agent accounts for 3% to 20% of the mass percentage of the dispersant; and the UV photoinitiator accounts for 0.1% to 0.5% of the mass percentage of the dispersant; and the crosslinking agent is selected from sodium methacryloyl alginate and methacryloyl hyaluronic acid. The preparation method includes the following steps: S1. Prepare a synthetic polymer material with double bonds at both ends; wherein the number of double bonds introduced in the synthetic polymer material with double bonds at both ends is at least two, and the double bonds include at least carbon-carbon double bonds; the synthetic polymer material is selected from at least one of polycaprolactone, polylactic acid, polylactic acid-glycolic acid copolymer and polyhydroxy fatty acid; S2. The synthetic polymer material with double bonds modified at both ends is used to synthesize polymer microspheres; S3. The polymer microspheres, the crosslinking agent, and the ultraviolet photoinitiator are dispersed and mixed with the dispersant in a predetermined mass ratio to obtain the synthetic polymer bio-ink of the water-soluble system; Step S1 includes: S11. After mixing and reacting the synthetic polymer solution, triethylamine and acryloyl chloride solution, filter the mixture and collect the filtrate to precipitate the synthetic polymer material with double bond modification at the hydroxyl end. S12. Prepare a synthetic polymer solution with double bonds at the hydroxyl end. Mix the synthetic polymer solution with double bonds at the hydroxyl end, 1-ethyl-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide and acrylamide and react them. Mix the mixed liquid after the reaction with deionized water and separate the liquid to obtain a synthetic polymer with double bonds at both ends. In step S11, the molar ratio of the synthetic polymer material to the triethylamine is 1:(2~5), and the molar ratio of the triethylamine to the acryloyl chloride is 1:(1~3). In step S12, the molar ratio of the synthetic polymer material with double bond modification at the hydroxyl end to the 1-ethyl-(3-dimethylaminopropyl)carbodiimide is 1:(2~5), the molar ratio of the 1-ethyl-(3-dimethylaminopropyl)carbodiimide to the N-hydroxysuccinimide is 1:(1~2), and the molar ratio of the synthetic polymer material with double bond modification at the hydroxyl end to acrylamide is 1:(2~5).

2. The method for preparing the water-soluble system of synthetic polymer bio-ink according to claim 1, characterized in that, In step S2, the method for synthesizing polymer microspheres from synthetic polymer materials with double bond modification at both ends is selected from one of the following: emulsion method, nanoprecipitation method, microfluidic technology, and supercritical fluid technology.

3. The method for preparing the synthetic polymer bio-ink of the water-soluble system according to claim 1, characterized in that, The ultraviolet photoinitiator is selected from at least one of LAP, photoinitiator 2959, photoinitiator 1173, and TPO.

4. A synthetic polymeric bio-ink with a water-soluble system prepared by the preparation method according to any one of claims 1 to 3.

5. An application of a synthetic polymer bio-ink based on the water-soluble system as described in claim 4, characterized in that, The process includes the following steps: 3D bioprinting and solidification of the synthetic polymer bio-ink of the water-soluble system to obtain a 3D printed scaffold.

6. The application of the synthetic polymer bio-ink of the water-soluble system according to claim 5, characterized in that, The water-soluble system's synthetic polymer bio-ink also contains cell fluid, which is used to print 3D-printed scaffolds containing cells.

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