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CN-122006827-A - Method and system for manufacturing micro-fluidic chip based on embedded direct writing and volume printing

CN122006827ACN 122006827 ACN122006827 ACN 122006827ACN-122006827-A

Abstract

The invention provides a method and a system for manufacturing a micro-fluidic chip based on embedded direct writing and volume printing. The method comprises the steps of preparing a photosensitive resin matrix with shear thinning characteristics and sacrificial ink, performing embedded direct writing forming to construct a three-dimensional runner framework, calculating and modulating a light field, generating the light field by adopting different algorithms according to the difference of the optical refractive indexes of the ink and the resin, photocuring a chromatographic volume to form a chip entity, and removing a sacrificial layer to obtain the microfluidic chip. The system integrates the direct writing and volume printing modules and is coordinated by the control unit. The method utilizes the sacrificial ink to avoid the blockage of the flow channel, ensures the smoothness of the inner wall by volume printing, improves the manufacturing quality and efficiency by being compatible with various material systems through light field calculation, realizes the composite manufacturing of the system and provides support for the large-scale production and application of the microfluidic chip.

Inventors

  • LI CHENHAO
  • PENG SHUAI
  • Hu Qinping
  • LIU YU

Assignees

  • 江南大学

Dates

Publication Date
20260512
Application Date
20260129

Claims (8)

  1. 1. The method for manufacturing the micro-fluidic chip based on the combination of embedded direct writing and volume printing is characterized by comprising the following steps of: s1, preparing materials, namely configuring a photosensitive resin matrix with shear thinning characteristics and sacrificial ink for constructing a runner framework; S2, embedded direct writing forming, namely placing the photosensitive resin matrix into a printing container, controlling a micro spray head to be inserted into the photosensitive resin matrix by utilizing a three-dimensional motion device, extruding the sacrificial ink according to a preset micro flow channel path, and suspending and fixing the extruded sacrificial ink by utilizing the yield stress of the photosensitive resin matrix to form a three-dimensional flow channel framework; s3, calculating and modulating a light field, namely acquiring the spatial distribution of the three-dimensional runner skeleton in a printing container and optical transmission parameters, and calculating and generating a multi-angle dynamic modulation light field based on a target three-dimensional model of a chip and combining the optical transmission parameters; S4, chromatographic volume photo-curing, namely projecting the dynamic modulation light field to the printing container by utilizing a volume printing system to enable the photosensitive resin matrix around the sacrificial ink to undergo photopolymerization crosslinking reaction to form a chip entity; And S5, removing the sacrificial layer, namely performing post-treatment on the solidified chip entity, and removing the internal sacrificial ink to obtain the microfluidic chip with the three-dimensional micro-channel structure.
  2. 2. The method for manufacturing a microfluidic chip based on embedded direct-write and volume printing composite of claim 1, wherein in step S3, a dynamic modulation light field is generated by combining optical transmission parameters, and the method comprises the steps of setting the optical transmission parameters to be unbiased transmission when the absolute value of the difference value of the optical refractive indexes of the sacrificial ink and the photosensitive resin matrix is smaller than or equal to 0.005, and generating the light field by adopting a standard Radon inverse transformation algorithm.
  3. 3. The method for manufacturing a microfluidic chip based on embedded direct-write and volumetric printing combination according to claim 1, wherein in step S3, a dynamically modulated light field is generated by combining optical transmission parameter calculation, comprising: When the absolute value of the difference between the optical refractive index of the sacrificial ink and the optical refractive index of the photosensitive resin matrix is larger than 0.005 or the sacrificial ink has light absorption property, a ray tracing correction model or a light attenuation compensation matrix is introduced into an algorithm for generating a light field, and the intensity distribution or the projection angle of the projected light is pre-corrected so as to offset the scattering, the refraction or the energy attenuation of the light when the light passes through the sacrificial ink.
  4. 4. A method of manufacturing a microfluidic chip based on a combination of embedded direct-write and volumetric printing as claimed in claim 3, wherein when the algorithm introduces a ray tracing correction model, the calculation algorithm identifies the shadow region formed by ink occlusion or refraction and compensates the energy threshold required for curing the resin in the region by enhancing the illumination dose at the corresponding voxel position for other projection angles.
  5. 5. The method for manufacturing the microfluidic chip based on the embedded direct writing and volume printing combination according to claim 1, wherein in the step S1, rheological properties of the photosensitive resin matrix are required to be satisfied, wherein the photosensitive resin matrix is in a gel state in a static state, has a yield stress of 10Pa or more, can support self weight and sacrificial ink embedded therein without sedimentation or diffusion, has a viscosity reduced to 10 Pa.s or less under a shearing force generated by the movement of the micro-jet head, and has a viscosity which returns to 80% of an initial value within 1 second after the shearing force is removed.
  6. 6. The method for manufacturing a microfluidic chip based on embedded direct-write and volume-printing composite according to claim 1, wherein in step S1, the sacrificial ink is a phase-change material or a water-soluble material, the phase-change material is selected from gelatin, agarose, poloxamer (Poloxamer) copolymer, polyethylene glycol or paraffin, the phase-change material is kept in a solid state or a high viscosity state in step S2 by controlling the temperature, the liquid flows out in step S5, and the water-soluble material is selected from polyvinyl alcohol, polyvinylpyrrolidone or a saccharide mixture, and the water-soluble material is removed in step S5 by water bath or ultrasonic dissolution.
  7. 7. The method for manufacturing the microfluidic chip based on the embedded direct writing and volume printing combination of claim 1, wherein the chromatography volume photo-curing process in the step S4 specifically comprises the steps of mounting a printing container containing a three-dimensional runner framework on a rotary platform, synchronously controlling the rotation angle of the rotary platform and the image projection of a spatial light modulator, projecting corresponding two-dimensional projection images into the printing container, and realizing omnibearing cumulative exposure, wherein the exposure time is controlled between 10 seconds and 120 seconds.
  8. 8. A composite manufacturing system for implementing the method of any one of claims 1-7, comprising: a printing container for holding a photosensitive resin substrate having thixotropic properties; The direct writing module comprises at least one precise displacement platform and a micro injection pump which are in triaxial linkage and is used for controlling the micro spray head to perform embedded printing in the photosensitive resin matrix; the volume printing module comprises a rotary objective table, a light source, a spatial light modulator and an optical lens group and is used for generating a chromatographic exposure light field; and the control unit is used for coordinating the path planning of the direct writing module, executing a light field correction algorithm according to the optical parameters of the ink and controlling the projection synchronization of the volume printing module.

Description

Method and system for manufacturing micro-fluidic chip based on embedded direct writing and volume printing Technical Field The invention relates to the technical field of 3D printing, in particular to a method and a system for manufacturing a micro-fluidic chip based on embedded direct writing and volume printing. Background The micro-fluidic chip is used as the core of the micro total analysis system and has extremely important application value in the fields of biological medicine detection, chemical synthesis, medicine screening, organ chip and the like. With the development of microfluidic technology, the demand for manufacturing three-dimensional complex flow channel structures inside a chip is growing. At present, the manufacturing method of the microfluidic chip mainly comprises a traditional soft lithography technology and an emerging 3D printing technology. The traditional soft lithography technique relies on a lithography silicon wafer as a mold, has complicated process steps, and is difficult to manufacture a complex runner with a true three-dimensional topology. Although the existing three-dimensional light curing (SLA/DLP) 3D printing technology can manufacture a three-dimensional structure, the three-dimensional structure is formed in a layer-by-layer superposition mode, so that a step effect is inevitably present, the inner wall of a runner is rough, and the flowing behavior of fluid under a microscale is affected. More serious, when printing a closed micro runner, uncured liquid resin is often trapped inside the slender runner due to capillary force, is difficult to discharge, is extremely easy to cause runner blockage, and limits the application of the uncured liquid resin in manufacturing the micro runner. The emerging volume Printing technology (volume 3D Printing/Computed Axial Lithography) is capable of curing the whole object at one time in a few seconds to tens of seconds through multi-angle light field projection, and has the advantages of no layering, high speed and smooth surface. However, volume printing is based on the principle of light energy accumulation, and it is difficult to manufacture a cavity structure with a high aspect ratio and a clear boundary inside an object. Because light passes through the cavity area without physical obstruction, excessive curing is likely to cause the flow channel to close. In addition, if a heterogeneous material is used as a barrier for the manufacture of the cavity, refraction and scattering of light are often caused, damaging the imaging quality, and causing printing failure. Therefore, a new manufacturing method is needed that combines the material flexibility of direct writing technology with the ultra-fast forming advantages of volume printing, while effectively solving the optical distortion problem caused by the introduction of heterogeneous materials. Therefore, we propose a method and a system for manufacturing a microfluidic chip based on embedded direct writing and volume printing. Content of the application Based on the above, it is necessary to provide a method and a system for manufacturing a microfluidic chip based on embedded direct writing and volume printing combination, aiming at the technical problems of low manufacturing efficiency, rough inner wall of a runner, difficult removal of residual resin, difficult manufacturing of an internal cavity by volume printing and the like in the existing microfluidic chip manufacturing technology, so that the manufacturing of the microfluidic chip can have the advantages of material flexibility and ultrafast forming, the optical distortion problem caused by the introduction of heterogeneous materials is effectively solved, and the manufacturing quality and efficiency are improved. The first aspect of the application provides a method for manufacturing a microfluidic chip based on embedded direct writing and volume printing, which comprises the following steps of firstly preparing materials, preparing a photosensitive resin matrix with shear thinning characteristic and sacrificial ink for constructing a runner skeleton, then performing embedded direct writing forming, placing the photosensitive resin matrix into a printing container, controlling a micro spray head to be inserted into the matrix by utilizing a three-dimensional motion device to extrude the sacrificial ink to form a three-dimensional runner skeleton, then performing light field calculation and modulation to obtain spatial distribution and optical transmission parameters of the three-dimensional runner skeleton, combining a chip target three-dimensional model to calculate and generate a multi-angle dynamic modulation light field, performing chromatography volume photo-curing, projecting the dynamic modulation light field by utilizing a volume printing system to enable the photosensitive resin matrix around the sacrificial ink to perform photopolymerization crosslinking reaction to form a chip entity, finally removing a sa