CN112477110A

CN112477110A - Solution bath near-field cell 3D printing forming device and forming method thereof

Info

Publication number: CN112477110A
Application number: CN202011218113.0A
Authority: CN
Inventors: 林锦新; 许泽亚; 赵超前; 陈燕; 黄婷婷; 卢衍锦
Original assignee: Fujian Institute of Research on the Structure of Matter of CAS
Current assignee: Fujian Institute of Research on the Structure of Matter of CAS
Priority date: 2020-11-04
Filing date: 2020-11-04
Publication date: 2021-03-12

Abstract

The invention discloses a solution bath near-field cell 3D printing forming device and a forming method thereof. The device comprises a near-field module, an extrusion-control module and a solution bath collection module; the extrusion-control module is arranged above the solution bath collection module; the near-field module is arranged between the extrusion-control module and the solution bath collection module, and is respectively connected with the extrusion-control module and the solution bath collection module; the solution bath collection module includes an insulated container, an electrolyte solution contained within the insulated container, and a deposition platform submerged in the electrolyte solution. During printing, filamentous cell ink is precisely printed on the deposition platform and can be quickly gelatinized when falling onto the deposition platform under the action of the electrolyte solution. The ink fineness of the device can reach 10 nm-100 mu m, the printing precision can reach 10 mu m, meanwhile, the device breaks away from the limit of ink viscosity, and realizes cell 3D printing with high precision, high degree of freedom and high cell activity.

Description

Solution bath near-field cell 3D printing forming device and forming method thereof

Technical Field

The invention belongs to the technical field of cell 3D printing, and particularly relates to a solution bath near-field cell 3D printing forming device and a forming method thereof.

Background

A structural unit consisting of various tissues in the human body that performs a certain or specific function is called an organ. A large amount of tissue and organ defects are caused by diseases, congenital malformations, traffic accidents and the like, so that the society has great demands on tissue and organ repair. Tissue and organ repair can be divided into biological repair and artificial repair according to different repair sources. The biological prosthesis can be divided into three types, namely an allomorphic prosthesis, an allomorphic prosthesis and a xenomorphic prosthesis. The alloplast prosthesis obtains the transplant donor from the patient, which has the greatest advantage of avoiding immunological rejection, but it needs to cut off the transplant from a healthy part, has limited source and causes secondary damage. Allogenic prostheses are donors belonging to the same species, often originating from donors, but face a certain risk of immunological rejection and are of limited origin. The donor and recipient of the xenogeneic prosthesis do not belong to the same species and are widely available, but the risk of immunological rejection is greater. Because the repairing method can not meet the requirements, the artificial repairing body is inoculated. However, the artificial substitute material has no biological characteristics, and is difficult to meet the real clinical treatment requirements. The theories and techniques of tissue engineering, which have appeared in the last 20 years, have shown a new role in the reconstruction of tissue and organs, and in providing biologically active grafts.

Tissue engineering refers to the research or development of human organ and tissue substitutes for replacing some or all functions of organs or tissues by applying the principles and methods of life science and engineering science. It relates to the cross fusion of a series of subjects of clinical medicine, biological materials science, cell biology, molecular biology, biological engineering and the like, and can be divided into a cell type and a non-cell type. In recent years, tissue engineering has achieved remarkable and enormous achievements, and significant scientific and attractive clinical applications have achieved some important progress as the frontier of medical science development. In addition, the development of bioremodelers, which are new technologies represented by cell printing, which are the tissue engineering infusion of fresh blood, has made it possible to construct viable tissues and organs in vitro.

In 3D cell printing technology, biological materials, biochemicals and living cells, as well as functional components, are precisely positioned layer by layer and placed in space, used to fabricate 3D structures. 3D cell printing is mainly divided into inkjet type, micro-extrusion type and laser-assisted printing. Inkjet printing is the most common type of printing for non-biological and biological applications, which is formed by controlled delivery of a liquid to a predetermined location. The ink-jet printing has the advantages of high printing speed, low cost, wide application range and the like. However, the risk of exposure of cells and materials to thermal and mechanical stress, low droplet directionality, non-uniform droplet size, frequent nozzle clogging, and unreliable cell encapsulation present considerable disadvantages for the application of inkjet printing in 3D bioprinting. Micro-extrusion bio-printing is typically comprised of a temperature controlled material handling and dispensing system, and a platen, which prints inks including, for example, hydrogels, biocompatible copolymers, and cell spheres; the main advantage of this is the ability to deposit very high cell densities, and achieving physiological cell densities in tissue engineered organs is a major goal in the field of bioprinting. However, cell viability is low (between 40-86%) due to the shear stress it exerts on cells in viscous fluids. Laser-assisted bioprinting is based on the principle of laser-induced forward transfer. Laser induced forward transfer technology was originally used to transfer metals and has been successfully applied to transfer biological materials such as peptides, DNA and cells. Because laser-assisted bioprinting is nozzle-less, the problem of cell or material clogging is avoided. The laser-assisted bioprinting has the advantages of good viscosity compatibility, high printing speed, high cell deposition density and the like. However, it is expensive and not suitable for printing multiple materials simultaneously.

The high-voltage electrostatic spinning technology is a method for preparing nano-micron fiber materials by utilizing the breakdown effect of a high-voltage electrostatic field on a high molecular solution, can easily prepare micro-and nano-scale one-dimensional fibers, and is widely applied to preparation of various nano fibers. However, electrospinning often does not allow precise control of the spatial location of the ink, which limits its ability to form three-dimensional products.

Disclosure of Invention

In order to solve the problems of low precision, low cell survival rate and the like of the existing cell 3D printing technology, the invention provides a solution bath near-field cell 3D printing forming device and a forming method thereof.

The invention provides the following technical scheme:

a solution bath near-field cell 3D printing forming device comprises a near-field module, an extrusion-control module and a solution bath collection module;

the extrusion-control module is arranged above the solution bath collection module;

the near-field module is arranged between the extrusion-control module and the solution bath collection module, and the near-field module is respectively connected with the extrusion-control module and the solution bath collection module;

the solution bath collection module includes an insulated container, an electrolyte solution contained within the insulated container, and a deposition platform submerged in the electrolyte solution.

According to an embodiment of the present invention, the extrusion-control module comprises a printing nozzle and a pneumatic extrusion control module, the printing nozzle being connected to a bottom end of the pneumatic extrusion control module.

According to an embodiment of the present invention, the number of printing heads may be at least 1, for example, 2, 3, 4 or more printing heads may be provided; optionally, when a plurality of print heads are provided, a coaxial print head or a non-coaxial print head may be selected. For example, a temperature adjusting module can be optionally arranged on one printing nozzle or a plurality of printing nozzles, the temperature adjusting module can be adjusted to-10-260 ℃, and the requirement of printing different cell inks can be met through temperature adjustment. As another example, the extrusion-control module may optionally be provided with one or more coaxial print heads whose inner and outer channels may print different cellular inks.

According to embodiments of the present invention, the print head may have a diameter of 0.3mm to 1mm, for example, a diameter of 0.4mm, 0.6mm or 0.8 mm. Further, for a coaxial print head, its inner diameter may be 0.15mm to 1.5mm, its outer diameter may be 0.3mm to 2mm, for example, 0.51mm inner diameter and 0.82mm outer diameter. For example, the material of the printing nozzle may be a biocompatible conductive metal material, such as medical stainless steel.

According to an embodiment of the present invention, the pneumatic extrusion control module comprises a gas inlet and a cell ink receiving chamber. Wherein, by adjusting the air pressure of the air inlet, the cell ink is extruded and the flow and the stop of the cell ink can be controlled. The cell ink is low-viscosity cell ink, for example, at least one of sodium alginate, silk fibroin, collagen, and the like can be used as the cell ink, and for example, sodium alginate can be used.

According to an embodiment of the present invention, the material of the pneumatic extrusion control module may be selected from bio-inert insulating materials, such as biocompatible PP (polypropylene) materials, and the like.

According to an embodiment of the present invention, the distance between the printing nozzle of the extrusion-control module and the liquid surface of the electrolyte solution in contact with air is 0.5 to 40mm, for example, 1 to 15mm, 3 to 10mm, 5 to 8 mm.

According to an embodiment of the present invention, the near field module is disposed at a side close to the printing nozzle. The near field module can be a high-voltage near field module or a low-voltage near field module, and is preferably a low-voltage near field module; further, the voltage of the low-voltage near-field module can be 0.1-10 kV, such as 0.5-8 kV, 1-7 kV and 3-5 kV.

According to an embodiment of the present invention, the near field module includes a positive electrode electrically connected to the print head and a negative electrode protruding into the electrolyte solution in the insulating container.

According to an embodiment of the present invention, the shape of the insulating container is not particularly limited, and may be a regular shape or an irregular shape, preferably a regular shape, such as a square or a cylindrical shape.

According to an embodiment of the present invention, the deposition platform may be a lifting deposition platform, preferably a deposition platform with precisely controllable lifting height. The deposition platform is used for receiving cell ink extruded, stretched and solidified from the printing nozzle; preferably, the deposition platform is required to gradually decrease as the number of printed layers increases; for example, the distance between the topmost end of the print deposited on the deposition platform and the liquid level at which the electrolyte solution is in contact with the air is maintained between 0.5 and 2mm, for example between 0.8 and 1.5mm, with 1mm being exemplary. Further, the material of the deposition platform is an inert biocompatible insulating material, such as glass or PP.

According to an embodiment of the invention, the deposition platform contains a sealing member preventing electrolyte solution from entering the dry zone along the side columns of the deposition platform.

According to an embodiment of the invention, the deposition platform contains a water and electricity isolation component to prevent leakage from dry areas and then into the electrolyte solution.

According to an embodiment of the present invention, the electrolyte solution is a conductive solution, and the electrolyte solution is capable of rapidly gelling a cell ink printed from a printing head. For example, the electrolyte solution may be selected from salt solutions, such as CaCl₂Solution, SrCl₂Solution and MgCl₂At least one of a solution and the like, exemplified by CaCl₂And (3) solution. Further, the electrolyte solution is connected to the ground.

According to an embodiment of the present invention, the 3D printing and forming apparatus further includes a 3D printing movement mechanism connected to the extrusion-control module. Wherein the 3D printing motion mechanism may be selected from motion mechanisms known in the art, for example, it may include a linear motion module, a rotational motion module, and a control mechanism connected to the linear motion module and the rotational motion module, respectively, which are connected to the extrusion-control module, respectively. The linear motion module comprises an X-axis linear motion mechanism, a Y-axis linear motion mechanism and a Z-axis linear motion mechanism, and can realize accurate printing of the position of the spray head on a three-dimensional space. The rotary motion module is a 4 th-axis rotary motion device which is directly connected with the printing spray head and can realize the movement of the spray head in a hemispherical surface. The control mechanism includes a servo motor controlled by a computer program. At X, Y, the track both ends of Z axis linear motion mechanism, all set up spacing inductor, ensured this motion's safe operation. Under the control of a program, a servo motor drives three linear motion mechanisms of X, Y and Z and a rotary motion mechanism to accurately move, and 3D printing and manufacturing on a three-dimensional space can be completed; meanwhile, due to the existence of the rotary motion mechanism, printing of more complex parts can be realized.

According to the embodiment of the invention, the 3D printing and forming device further comprises a 3D printing support platform, the 3D printing movement mechanism is arranged on the 3D printing support platform, and the insulating container is arranged on the 3D printing support platform.

Further, the invention also provides a cell printing and molding method using the solution bath near-field cell 3D printing device, which comprises the following steps: the cell ink extruded from the printing nozzle is pulled into filaments under the action of electric field force; the filamentous cell ink is accurately printed on the deposition platform, and the cell ink falling on the deposition platform under the action of the electrolyte solution is quickly gelatinized to finish the printing of one layer; then the deposition platform descends to start the printing of the next layer;

the distance between the top of the print and the surface of the liquid in contact with the electrolyte solution and air during printing of each layer is kept between 0.5 and 3mm, for example between 0.8 and 1.5mm, illustratively 1 mm.

According to an embodiment of the invention, the cellular ink is squeezed out of the print head under the action of air pressure, which is the driving force for squeezing out the cellular ink. For example, the pressure may be between 0.05 and 1MPa, such as between 0.05 and 0.4MPa, between 0.05 and 0.6MPa, between 0.05 and 0.8 MPa.

According to an embodiment of the present invention, the electric field force is generated by a near field module, which may be a high voltage near field module or a low voltage near field module, preferably a low voltage near field module. For example, the voltage of the low-voltage near-field module may be 0.1-10 kV, such as 0.5-8 kV, 1-7 kV, and 3-5 kV.

According to an embodiment of the present invention, the diameter of the cell ink filament may be 10nm to 100 μm, for example 30nm to 90 μm, 500nm to 50 μm, 1 to 10 μm, due to the effect of the electric field force.

According to an embodiment of the invention, the print head has the meaning as described above. Furthermore, the printing nozzle can be a multi-printing nozzle structure, mixed printing of cell ink and the support material can be realized, and the support material, the cell ink and the culture medium thereof can be printed separately. For example, the print heads can be divided into two types, one print head to print the cells and their culture medium and the other print head to print the scaffold. Further, the nozzle that prints the cells may employ multiple printing nozzles to print different cells. In particular, a coaxial printing head may also be used, in which the inner and outer channels may print different cellular inks.

According to an embodiment of the present invention, the 3D printing motion mechanism, the deposition platform and the electrolyte solution all have the meaning as described above.

According to an embodiment of the present invention, the cell printing and molding method comprises the steps of:

(1) generating air pressure through an extrusion-control module to extrude the cell ink from the printing nozzle;

(2) a potential difference is generated between the positive electrode and the negative electrode of the low-voltage near-field module, so that an electric field is generated;

(3) under the action of an electric field force, the extruded cell ink is drawn into a filament, the cell ink is accurately printed on a deposition platform under the control of a 3D printing movement mechanism, and the cell ink falling on the deposition platform is rapidly gelatinized under the action of an electrolyte solution to finish the printing of one layer; then the deposition platform descends to start the printing of the next layer;

the distance between the topmost end of the print and the surface of the liquid in contact with the electrolyte solution and air during printing of each layer is maintained between 0.5 and 3mm, for example between 0.8 and 1.5mm, illustratively 1 mm.

The invention has the beneficial effects that:

1. according to the invention, the fineness of the cell 3D printing ink is greatly improved under the action of the electric field force of the near-field module. The printing method can realize the finest fineness of 10nm of the cell ink, so that the 3D printing accuracy of the cells is improved, and the printing accuracy can reach 10 mu m. Meanwhile, the device has adjustable fineness, and can meet the printing requirements of ink with different fineness.

2. The solution bath collection module is arranged in the 3D printing and forming device, so that the ink is immediately gelatinized at the moment of extrusion, and collapse caused by too low viscosity of the ink is avoided. Meanwhile, the cell ink with low viscosity can also have higher cell density, higher cell activity and better cell 3D printing performance.

3. For the near-field module of the present invention, the positive electrode is a metal showerhead, and the negative electrode is in contact with the electrolyte liquid surface. As the deposition platform continuously descends along with printing and the highest point of a printing piece is always lower than the liquid level of the electrolyte solution, the liquid level is always kept horizontal, and the electrostatic field is also always uniform. This avoids the problem of electrostatic field disturbance due to the increasing thickness of the print, allowing printing of thicker prints.

4. The invention can realize simultaneous printing of multiple nozzles and can print different cell inks. Meanwhile, the cell ink and the matrix thereof can be printed separately from the bracket material, so that the cost can be saved better, and the printed product has more complex structure and function.

5. Compared with the traditional electrostatic spinning, the method can accurately control the deposition site of the cell ink, so that the method has the capability of printing workpieces with complex geometric structures.

Drawings

Fig. 1 is a schematic structural diagram of a near-field 3D printing and molding apparatus according to embodiment 1.

Fig. 2 is a schematic structural diagram of a gantry-type 3D printing movement mechanism in the 3D printing and forming device according to embodiment 1.

Fig. 3 is a schematic structural diagram of a coaxial printing nozzle in the 3D printing and molding apparatus according to embodiment 1.

Reference numerals: 1-13D printing support platform 1-23D printing movement mechanism, 1-3 extrusion-control module, 1-4 cell ink accommodating cavity, 1-5 low-voltage near-field module, 1-6 printing nozzle, 1-7 insulating container, 1-8 lifting deposition platform and 1-9 conductive electrolyte solution;

2-1X axis linear motion mechanism, 2-2Y axis linear motion mechanism, 2-3Z axis linear motion mechanism and 2-4 th axis rotary motion mechanism;

3-1 coaxial printing nozzle.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are only for illustrating the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that various changes or modifications can be made by those skilled in the art after reading the disclosure of the present invention, and such equivalents also fall within the scope of the invention.

The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.

Example 1

The solution bath near-field cell 3D printing and forming mechanism shown in FIG. 1 comprises a 3D printing support platform 1-1, a 3D printing movement mechanism 1-2, an extrusion-control module 1-3, a cell ink accommodating cavity 1-4, a low-pressure near-field module 1-5, a printing spray head 1-6 and a solution bath collecting module. The solution bath collection module includes an insulated container 1-7, a conductive electrolyte solution 1-9 disposed within the insulated container 1-7, and a lifting deposition platform 1-8 immersed within the conductive electrolyte solution 1-9.

The 3D printing mechanism 1-2 is a gantry type 3D printing mechanism, as shown in fig. 2, and includes a linear motion module, a rotational motion module, and a control mechanism respectively connected to the linear motion module and the rotational motion module, and the linear motion module and the rotational motion module are respectively connected to the extrusion-control module 1-3. The linear motion module mainly comprises an X-axis linear motion mechanism 2-1, a Y-axis linear motion mechanism 2-2 and a Z-axis linear motion mechanism 2-3 and is used for realizing the accurate control of the position of the printing spray head 1-6 on a three-dimensional space. The rotary motion module comprises a 4 th-axis rotary motion mechanism 2-4 which is directly connected with the printing spray heads 1-6 and is used for realizing the motion of the printing spray heads 1-6 in a hemispherical surface. The control mechanism mainly comprises a servo motor controlled by a computer program, and limit sensors are arranged at two ends of a track of the X-axis, Y-axis and Z-axis linear motion mechanism, so that the safe operation of the motion mechanism is guaranteed. Under the control of a program, the servo motor drives three linear motion mechanisms of X, Y and Z and a rotary motion mechanism to accurately move, and 3D printing and manufacturing on a three-dimensional space can be completed. Meanwhile, due to the existence of the rotary motion mechanism, printing of more complex parts can be realized.

The extrusion-control module 1-3 is arranged above the solution bath collection module and comprises a pneumatic extrusion control module and a printing nozzle, the pneumatic extrusion control module comprises a gas inlet and a cell ink accommodating cavity 1-4, and the lower end of the cell ink accommodating cavity 1-4 is connected with the printing nozzle 1-6. The cell ink is extruded by adjusting the air pressure (the air pressure range is 0.05-1MPa) of the air inlet, and the extrusion speed of the cell ink is controlled. The cell ink in the cell ink accommodating chambers 1 to 4 has low viscosity and enables better survival of the cells. The pneumatic extrusion control module is made of a biocompatible PP material.

The printing spray head 1-6 is a medical stainless steel spray head and is connected with the positive pole of a low-voltage near-field module 1-5 (the voltage range is 0.1-10 kV). The printing nozzles 1 to 6 are coaxial printing nozzles, and the structure of the printing nozzles is shown in figure 3, wherein the inner diameter is 0.15mm to 1.5mm, and the outer diameter is 0.3mm to 2 mm.

The low-voltage near-field module 1-5 is arranged on one side close to the printing spray head 1-6, the voltage of the low-voltage near-field module 1-5 is 0.1-10 kV, and the negative electrode of the low-voltage near-field module 1-5 extends into the conductive electrolyte solution 1-9 in the insulating container 1-7.

The insulating container 1-7 is in the shape of a regular cylinder, and the lifting deposition platform 1-8 is used for receiving finally extruded, stretched and solidified cell ink. The lifting deposition platforms 1-8 gradually descend along with the increase of the number of printing layers, and the distance between the topmost end of the printing piece deposited on the lifting deposition platforms 1-8 and the liquid level of the conductive electrolyte solution 1-9 in contact with air is kept at 1 mm. The deposition platform contains sealing component and water and electricity isolation component, and sealing component can prevent that electrolyte solution from getting into the dry zone along the deposition platform side post, and water and electricity isolation component can prevent to spread into in the electrolyte solution behind the dry zone electric leakage. The conductive electrolyte solution 1-9 is connected to the ground. The insulating containers 1-7 and the lifting deposition platforms 1-8 are made of inert biocompatible insulating PP materials. The conductive electrolyte solution 1-9 is CaCl with good conductivity₂And (3) solution.

Under the working state, the cell ink is extruded out through the printing nozzles 1-6 under the action of air pressure, is stretched and thinned under the action of the electric field force under the action of the low-pressure near-field module 1-5, has the finest fineness of 10nm, and is deposited on the lifting deposition platform 1-8. The conductive electrolyte solution 1-9 has a gelation effect on the cell ink 1-4, and the printing ink 1-4 falling on the lifting deposition platform 1-8 can quickly form gel. The printing spray head 1-6 moves along with the 3D printing movement mechanism 1-2 to complete the printing of one layer of patterns, and then the lifting deposition platform 1-8 descends to continue the printing of the next layer of patterns. During the printing process, the distance between the topmost end of the printed piece and the liquid surface of the conductive electrolyte solution 1-9 in contact with the air is always kept at 1 mm.

The 3D printing movement mechanism 1-2 is arranged on the 3D printing support platform 1-1, and the insulating container 1-7 is arranged on the 3D printing support platform 1-1.

Example 2

Different from the embodiment 1, the number of the printing spray heads is multiple, and the plurality of printing spray heads are provided with the spray head temperature adjusting modules for realizing adjustment at-10 to 260 ℃ so as to meet the printing requirements of different cells.

Example 3

Different from the embodiment 1, the printing nozzle has a multi-nozzle structure, and the nozzles are divided into two types: a nozzle is used for printing cells and cell culture matrixes thereof and can print a plurality of different cells; another type of printhead is used to print a support. The same as embodiment 1, the printing nozzle is also a coaxial printing nozzle, and the inner channel and the outer channel can print different cell ink.

Example 4 solution bath near-field cell 3D printing molding method

The embodiment is a solution bath near-field cell 3D printing and forming method, which is completed by the solution bath near-field cell 3D printing and forming device provided in embodiment 3.

The solution bath near-field cell 3D printing and forming method comprises the following steps: generating air pressure through an extrusion-control module to extrude the cell ink from the printing nozzle; a potential difference is generated between the positive electrode and the negative electrode of the low-voltage near-field module, so that an electric field is generated; under the action of an electric field force, the extruded cell ink is drawn into a filament, and the cell ink is accurately printed on a deposition platform under the control of a 3D printing movement mechanism; under the action of electrolyte solution, the cell ink falling on the deposition platform completes gelation at the moment of deposition; and after the printing of one layer of pattern is finished, the deposition platform descends, the printing of the next layer is started, and the distance between the topmost part of the printed piece and the liquid level of the contact of the electrolyte solution and the air is kept at 1mm all the time in the printing process.

Wherein, the power for extruding the cell ink is air pressure, and the pressure is 0.4 Mpa. The electrostatic field is realized by introducing a low-voltage near field, and the voltage of the low-voltage near field is 2.5 kV. The cell ink is deposited under the action of an electrostatic field, and filaments which are thinner than those deposited under the gravity condition can be obtained, the diameter is controlled to be 10 nm-1 mu m, and the printing precision can reach 10 mu m. The cell ink uses sodium alginate as a template agent and 0.1M CaCl₂The solution serves as an electrolyte solution.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A solution bath near-field cell 3D printing and forming device is characterized by comprising a near-field module, an extrusion-control module and a solution bath collection module;

2. The solution bath near-field cell 3D printing and forming device according to claim 1, wherein the extrusion-control module comprises a printing nozzle and a pneumatic extrusion control module, and the printing nozzle is connected with the bottom end of the pneumatic extrusion control module.

3. The solution bath near-field cell 3D printing and forming device according to claim 2, wherein the number of the printing nozzles is at least 1;

optionally, when a plurality of printing nozzles are arranged, a coaxial printing nozzle or a non-coaxial printing nozzle is selected;

optionally, a temperature adjusting module is arranged on one printing spray head or a plurality of printing spray heads, and the temperature adjusting module can be adjusted at the temperature of-10-260 ℃;

preferably, the extrusion-control module is optionally provided with one or more coaxial printing nozzles, the inner channels and the outer channels of which print different cellular inks;

preferably, the diameter of the printing nozzle is 0.3mm-1 mm;

preferably, the inner diameter of the coaxial printing nozzle is 0.15mm-1.5mm, and the outer diameter is 0.3mm-2 mm;

preferably, the printing nozzle is made of a biocompatible conductive metal material.

4. The solution bath near-field cell 3D printing and forming device according to claim 2 or 3, wherein the pneumatic extrusion control module comprises a gas inlet and a cell ink accommodating cavity;

preferably, the cell ink is low-viscosity cell ink, for example, the cell ink contains at least one of sodium alginate, silk fibroin and collagen;

preferably, the material of the pneumatic extrusion control module is selected from a bio-inert insulating material, such as a biocompatible PP material;

preferably, the distance between the printing nozzle of the extrusion-control module and the liquid surface of the electrolyte solution in contact with air is 0.5-40 mm.

5. The solution bath near-field cell 3D printing and forming device according to any one of claims 1 to 4, wherein the near-field module is arranged on one side close to the printing nozzle, and the near-field module is a high-voltage near-field module or a low-voltage near-field module, preferably a low-voltage near-field module;

preferably, the near-field module comprises a positive electrode and a negative electrode, the positive electrode is electrically connected with the printing spray head, and the negative electrode extends into the electrolyte solution in the insulating container;

preferably, the shape of the insulating container is a regular shape or an irregular shape, preferably a regular shape.

6. The solution bath near-field cell 3D printing and forming device according to any one of claims 1 to 5, wherein the deposition platform is a lifting deposition platform, preferably a lifting deposition platform with precisely controllable height, and is used for receiving cell ink extruded, stretched and solidified from a printing spray head;

preferably, the deposition platform gradually decreases as the number of printed layers increases;

preferably, the distance between the topmost end of the print piece deposited on the deposition platform and the liquid surface of the electrolyte solution in contact with air is kept between 0.5 and 2 mm;

preferably, the deposition platform is made of an inert biocompatible insulating material;

preferably, the electrolyte solution is a conductive solution, and the electrolyte solution can rapidly gel the cell ink printed from the printing nozzle;

preferably, the electrolyte solution is selected from a salt solution;

preferably, the electrolyte solution is connected to ground.

7. The solution bath near-field cell 3D printing and forming device according to any one of claims 1-6, wherein the 3D printing and forming device further comprises a 3D printing motion mechanism connected with the extrusion-control module;

preferably, the 3D printing motion mechanism comprises a linear motion module, a rotational motion module, and a control mechanism connected to the linear motion module and the rotational motion module, respectively, and the linear motion module and the rotational motion module are connected to the extrusion-control module, respectively; the linear motion module comprises an X-axis linear motion mechanism, a Y-axis linear motion mechanism and a Z-axis linear motion mechanism, the rotary motion module is a 4 th-axis rotary motion device which is directly connected with the printing spray head, and the control mechanism comprises a servo motor controlled by a computer program.

8. The solution bath near-field cell 3D printing and forming device according to any one of claims 1 to 7, further comprising a 3D printing support platform, wherein the 3D printing motion mechanism is disposed on the 3D printing support platform, and the insulating container is disposed on the 3D printing support platform.

9. A cell printing and molding method using the solution bath near-field cell 3D printing device according to any one of claims 1 to 8, comprising the steps of: the cell ink extruded from the printing nozzle is pulled into filaments under the action of electric field force; the filamentous cell ink is accurately printed on the deposition platform, and the cell ink falling on the deposition platform under the action of the electrolyte solution is quickly gelatinized to finish the printing of one layer; then the deposition platform descends to start the printing of the next layer;

during the printing of each layer, the distance between the top of the printed matter and the liquid surface in contact with the electrolyte solution and air is kept between 0.5 and 3 mm.

10. The method of claim 9, wherein the cellular ink is forced out of the print head under air pressure;

preferably, the air pressure is between 0.05 and 1 MPa;

preferably, the electric force is generated by a near field module; preferably, the voltage of the near field module is 0.1-10 kV;

preferably, the diameter of the cell ink filament is 10nm to 100 μm.