Cross-scale structure-material rheology detection system

Abstract

The invention discloses a cross-scale structure-material rheology detection system, which belongs to the technical field of biomedical engineering, and realizes cross-scale geometric imaging by combining optical coherence tomography and laser scanning confocal or fluorescence imaging common optical path design. Geometric-mechanical synchronous observation and analysis of in-situ real-time monitoring and cross-scale synchronous monitoring of stress and strain of a multi-scale structure are supported; the biological 3D printing based on the six-axis robot supports in-situ printing on a rheology detection platform, so that a standardized rheology detection model of a bionic tissue inherent structure is constructed, and automatic and high-throughput bio-ink geometry-mechanics synchronous observation is supported; a multi-physics field coupling measurement model in a dynamic microenvironment is constructed, and a printing structure-material mechanics coupling mechanism is analyzed based on a rheology-structure data quantitative mapping model of deep learning. The system is based on rheology detection of the structure, and the theoretical and technical limitations of multi-scale structural mechanical property monitoring are solved.

Description

Technical Field

[0001] This invention relates to the field of biomedical engineering technology, specifically to a multi-scale structure-material rheology detection system. Background Technology

[0002] The mechanical properties of biomaterials are core physical factors regulating the occurrence and development of tissues and organs. Mechanical signals influence cell differentiation, migration, and spatial arrangement, determining the stability and plasticity of structures during organ development. Bio-3D printing can endow biomaterials / cells with complex multi-scale biomimetic structures, providing a revolutionary research tool for fields such as tissue and organ regeneration. However, current technologies face significant theoretical and technological gaps in detecting the mechanical properties of multi-scale structures and analyzing structure-mechanical coupling mechanisms. Rheometers, as key equipment for measuring the viscoelasticity of materials, obtain core parameters such as storage modulus and loss modulus by applying shear stress and measuring strain response, and are widely used in the mechanical characterization of biomaterials. However, traditional rheometers face three key technological challenges. (1) Lack of structural variables: Traditional rheometers are limited to detecting only standard disk and cone-shaped samples, ignoring the reconstruction effect of the inherent multi-scale structure of tissue on stress distribution; (2) Lack of dynamic monitoring: Existing equipment lacks the ability to monitor multi-scale structural deformation in situ in real time, making it difficult to capture nonlinear mechanical responses during dynamic loading; (3) Insufficient multi-field coupling analysis: A multi-physics field coupling analysis method for structural deformation and material rheology in dynamic micro-environment has not yet been established. These shortcomings restrict the analysis and control of the coupling mechanism of tissue and organ structure-mechanics-morphology-function reconstruction, which is an urgent problem to be solved. Although there are many bioprinting devices in the existing technology, such as a micro 3D printing device for active stem cells based on PL-level piezoelectric nozzle technology disclosed in existing patent 201910991116.9, and an intelligent photopolymerization bioprinter disclosed in existing patent 202110319051.0, the existing technologies cannot effectively solve the above problems. Summary of the Invention

[0003] The purpose of this invention is to provide a cross-scale structure-material rheology detection system. By combining optical coherence tomography with a common optical path design of laser scanning confocal or fluorescence imaging, it achieves cross-scale geometric imaging. It supports in-situ real-time monitoring of stress and strain in multi-scale structures and simultaneous geometric-mechanical observation and analysis across scales. Based on a 6-axis robot, bio-3D printing supports in-situ printing on a rheology detection platform to construct a standardized rheology detection model of the inherent structure of biomimetic tissues, supporting automated, high-throughput simultaneous geometric-mechanical observation of bio-inks. It constructs a multi-physics coupling measurement model in a dynamic microenvironment and a deep learning-based rheology-structure data quantitative mapping model to analyze the coupling mechanism of printed structure-material mechanics. This system, based on structure rheology detection, overcomes the theoretical and technical limitations of monitoring the mechanical properties of multi-scale structures, promotes the deep decoding of the structure-mechanics-morphology-function reconstruction mechanism of tissues and organs, and provides new scientific tools for tissue and organ manufacturing, regenerative medicine, and drug development.

[0004] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution: a multi-scale structure-material rheology detection system, comprising, A multi-scale 3D high-resolution geometric imaging module is used to achieve imaging and detection of printed models; The module for simultaneous observation and coupling analysis of the geometry and mechanics of bio-ink is used to realize simultaneous microscopic observation of hydrogel interfaces under rheological loading. High-throughput automation hardware support module, used to provide the loading platform; The server and control analysis modeling module is used to analyze the dynamic coupling mechanism of the structure-rheological multidimensional parameters of bio-ink; The functional remodeling testing platform is used for screening bio-inks for different organoids and for tissue printing, as well as for correlation analysis of tissue morphogenesis and functional remodeling.

[0005] The solution of this invention breaks through the limitations of single imaging, realizes dynamic imaging across micrometer-millimeter scales, and solves the problem that traditional detection methods cannot simultaneously achieve both resolution and depth.

[0006] According to one embodiment of the present invention, the multi-scale three-dimensional high-resolution geometric imaging module has a common optical path, which is a combination of optical coherence tomography and fluorescence microscopy or a combination of optical coherence tomography and confocal microscopy.

[0007] According to one embodiment of the present invention, the common optical path is a combined optical path for optical coherence tomography and fluorescence microscopy, including an FM module, a co-processing module connected to the FM module, an OCT module having a common optical path with the FM module, and a common optical path module for focusing the optical paths of the FM module and the OCT module onto the same sample.

[0008] According to one embodiment of the present invention, the common optical path is a combined optical path for optical coherence tomography and confocal microscopy, including a CLSM module, a coprocessing module connected to the CLSM module, an OCT module having a common optical path with the CLSM module, and a common optical path module for focusing the optical paths of the CLSM module and the OCT module onto the same sample.

[0009] This invention overcomes the limitations of single imaging techniques by combining optical coherence tomography (OCT) with fluorescence microscopy (FM) or confocal microscopy (CLSM). OCT can monitor macroscopic structural changes in real time, FM can capture microscopic information of labeled molecules, and CLSM provides submicron-level detailed imaging. A shared optical path ensures that both focus on the same sample, and with time-synchronized control, it achieves micron- to millimeter-scale dynamic imaging. This combines the deep structure detection capabilities of OCT with the high-resolution microscopic characterization advantages of FM / CLSM, overcoming the limitations of traditional imaging methods that struggle to simultaneously achieve both resolution and depth. It provides precise and coherent cross-scale dual-modal data support for subsequent structure-mechanical coupling analysis.

[0010] According to one embodiment of the present invention, in terms of the timing control of the multi-scale three-dimensional high-resolution geometric imaging module, a high-precision synchronous triggering module controlled by FPGA is adopted to generate pulse signals with strict timing alignment, synchronously driving OCT signal acquisition and fluorescence camera exposure, ensuring timing synchronous triggering and real-time synchronous storage of multi-channel data, or the K triggering and A triggering signals of the OCT light source are adopted to ensure the synchronous sampling of the interference spectrum at wavenumber intervals and the movement of the scanning galvanometer.

[0011] According to one embodiment of the present invention, a bio-ink geometry-mechanical synchronous observation and coupling analysis module includes an OCT module, an FM module, a rheometer module, and a robot collaborative control module supporting high-throughput automated hardware. By integrating the OCT module, FM module, rheometer module, and robot collaborative control module, this module overcomes the limitations of traditional equipment's separation of structure and mechanical monitoring, enabling synchronous microscopic dynamic observation of hydrogel interfaces under rheological loading. It supports spatiotemporal structural imaging and multidimensional physical quantity acquisition coordinated with pressure loading, providing coherent data for the geometry-mechanical coupling analysis of high-throughput bio-inks.

[0012] According to one embodiment of the present invention, a high-throughput automated hardware support module includes a clean-grade 6-axis robotic arm and a modular work terminal, a material storage module and a temperature control module, a multi-functional bio-ink cartridge workstation, and a Class 100 external environment control chamber. The 6-axis robotic arm achieves nanometer-level positioning and fully automated operation, and works with the modular terminal to complete 12 steps including ink loading, transfer, and sample loading, significantly improving detection efficiency; the material storage and temperature control module precisely controls the temperature to ensure the stability of the bio-ink; the Class 100 external environment control chamber provides a clean environment to avoid contamination; and the multi-functional bio-ink cartridge workstation is adaptable to various types of operations.

[0013] According to one embodiment of the present invention, the server and control analysis modeling module support efficient collaborative control and automated operation among various modules, including synchronous timing control and signal processing of the bio-ink geometry-mechanical synchronous observation and coupling analysis module, multi-module collaborative operation control of the 6-axis robotic arm high-throughput automated hardware support module, rheological-structural coupling analysis modeling, and tissue morphology-functional remodeling correlation analysis. The server and control analysis modeling module supports precise timing control and signal processing of the bio-ink geometry-mechanical synchronous observation module, ensuring the synchronization of structural-mechanical data and reducing timing errors. Simultaneously, through rheological-structural coupling analysis modeling and tissue morphology-functional remodeling correlation analysis, it overcomes the limitations of traditional decentralized data processing, deeply analyzes the dynamic correlation mechanism between the structure and mechanical properties of bio-ink, and tissue morphology and function, providing quantitative basis for bio-ink screening and tissue printing optimization.

[0014] According to one embodiment of the present invention, the server and control analysis modeling module are capable of machine learning, and the learning steps are as follows: Step 1), Data Acquisition: Acquire data from OCT, FM, and rheometer. Step 2), data preprocessing, which involves cleaning, normalizing, and feature selection of the collected data; Step 3), geometric-mechanical collaborative testing and analysis, namely geometric testing and analysis including the length, width and height of the printed model, filament diameter, pore connectivity, volume, fluorescence, etc.; mechanical testing and analysis including the viscosity, storage modulus, strain, loss modulus, yield stress, etc. of the printed filament.

[0015] Step 4) Learning a geometry-mechanical coupling model based on graph learning, such as performing a graph learning model based on S samples on matrix data with feature dimensions at different time points to achieve M+N dimensional features.

[0016] Step 5) After performing machine learning, performance evaluations are obtained, such as mean squared error and coefficient of determination. Results analysis and interpretation are then performed, such as feature importance analysis and model interpretation techniques, and the final model is output.

[0017] This invention collects multi-source data from OCT, FM, and rheometers, and improves data quality through preprocessing; then, it accurately extracts key features through geometric and mechanical analysis; it combines graph learning models to learn feature matrices at multiple time points, achieving multi-dimensional feature coupling and breaking through the limitations of traditional static analysis; finally, it outputs a reliable model through performance evaluation and feature interpretation.

[0018] According to one embodiment of the present invention, the server and control analysis modeling module rely on the cross-scale three-dimensional high-resolution geometric imaging module to acquire the time series data of structural evolution and rheological response parameters of bio-ink during the phase transition process, and construct a dynamic database containing multi-dimensional structural features and rheological indices.

[0019] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention solves the problem of poor coordination caused by the dispersed layout of traditional equipment; it breaks through the limitations of single imaging, realizing cross-scale characterization of microstructure and macromorphology, and making up for the shortcomings of traditional detection in balancing resolution and depth; the data support module synchronously stores multimodal data and extracts OCT features, providing accurate input for structure-mechanical coupling analysis and solving the problem of low-contrast bio-ink signal extraction. The method of this invention not only takes into account the cross-scale characterization of micro-macrostructures, but also strengthens the correlation analysis of structure-mechanical properties, improving the coherence, accuracy and reliability of detection results. Attached Figure Description

[0020] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a cross-scale structure-material rheology detection system according to the present invention; Figure 2 This is a schematic diagram of the common optical path scheme for OCT and FM in this invention; Figure 3 This is a schematic diagram of the common optical path scheme of OCT and CLSM in this invention; Figure 4 This is a schematic diagram of the bio-ink geometry-mechanical synchronous observation and coupling analysis module of the present invention; Figure 5 This is a schematic diagram of the pollution-free operation process of the cell bio-ink of the present invention; Figure 6 This is a flowchart of the machine learning-based process in Example 1.

[0022] Figure labeling: 10. High-throughput automated hardware support module; 20. Multifunctional bio-ink cartridge workstation; 30. Material storage and temperature control module; 40. Class 100 external environment control chamber; 50. Bio-ink geometric-mechanical synchronous observation and coupling analysis module; 60. Cross-scale three-dimensional high-resolution geometric imaging module; 70. Server and control analysis modeling module; 80. Functional redesign test platform. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] Example 1: This embodiment discloses a multi-scale structure-material rheology testing system, such as... Figure 1 As shown, including, 60-scale three-dimensional high-resolution geometric imaging module; Module 50 for simultaneous observation and coupling analysis of the geometry and mechanics of bio-ink; High-throughput automation hardware support module 10; Server and Control Analysis Modeling Module 70; Functional redesign test platform 80.

[0026] The multi-scale three-dimensional high-resolution geometric imaging module 60 incorporates optical coherence tomography (OCT) and fluorescence microscopy (FM) or confocal microscopy (CLSM) in a shared optical path design. OCT enables real-time dynamic monitoring of structural changes in cell bio-ink and printed tissue; FM monitors tracers, proliferation markers, and other specifically labeled target molecules, precisely capturing the spatial localization, metabolic activity, and functional phenotypic information of cells, achieving quantitative characterization of key parameters such as cell viability and proliferation kinetics; or CLSM provides sub-micron lateral resolution detailed imaging of fluorescently labeled cell structures.

[0027] Among them, the OCT and FM share the same optical path design, such as Figure 2As shown, the blue shaded area represents the fluorescence microscopy imaging module (FMModule), and the red shaded area represents the OCT imaging module (OCT Module). These two modules are integrated through a shared optical path module (CommonModule 2) to achieve cross-scale (micrometer-millimeter) dual-modal dynamic imaging of macroscopic three-dimensional morphology and microscopic cell distribution / activity. The OCT module can employ swept-frequency OCT (SS-OCT) based on a swept-frequency light source, or spectral-domain OCT (SD-OCT). Taking SS-OCT as an example, a near-infrared swept-frequency light source (SS) is used. After being split by a 90 / 10 fiber coupler (FC1), the light is then emitted as sample light and reference light through fiber circulators (CIR1, CIR2) and polarization controllers (PC1, PC2), respectively. Simultaneously, the FM module, connected to the common processing module (CommonModule 1), shares a common optical path module (CommonModule 2) with the FM module, used to focus the optical paths of the FM and OCT modules onto the same sample.

[0028] An optional embodiment employs a dual-band dichroic mirror, compatible with the near-infrared light (1300nm) of OCT and the excitation light (488nm / 561nm) of fluorescence microscopy; and selects an objective lens with a long working distance and high NA to meet the penetration depth requirements of OCT and the resolution requirements of fluorescence microscopy.

[0029] In terms of timing control, the CommonModule 1 employs a high-precision synchronous triggering module controlled by an FPGA to generate timing-aligned pulse signals that synchronously drive OCT signal acquisition and fluorescence camera exposure, ensuring synchronous triggering and real-time synchronous storage of multi-channel data, thus reducing timing errors. Simultaneously, by adjusting the duty cycle and phase delay of fluorescence excitation, signal crosstalk between the excitation light and OCT imaging is avoided, ensuring the signal-to-noise ratio of structural and functional imaging. Based on this integrated OCT-fluorescence microscope system, significant limitations of single imaging technologies can be overcome, enabling cross-scale (micrometer-millimeter) dual-modal dynamic imaging of bio-inks. This allows for dynamic observation of the macroscopic three-dimensional morphology (porosity, interlayer bonding, etc.) and microscopic cell distribution / activity (vivimetry and proliferation status of fluorescently labeled cells) of bio-inks.

[0030] OCT and CLSM shared optical path design, such as Figure 3As shown, the blue shaded area represents the laser scanning confocal module (CLSMModule), and the red shaded area represents the optical coherence tomography (OCT Module). The OCT module and the CLSM module share a common scanning optical path (CommonModule 2). Wavelength separation and merging are achieved through a dichroic mirror filter wheel (DMFilerWheel 2), focusing the light onto the same sample. The OCT module can employ swept-frequency OCT (SS-OCT) based on a swept-frequency light source, or it can employ spectral-domain OCT (SD-OCT). Taking SS-OCT as an example, a near-infrared swept-frequency light source (SS) is used. After being split by a 90 / 10 fiber coupler (FC1), the light is then emitted as sample light and reference light through fiber circulators (CIR1, CIR2) and polarization controllers (PC1, PC2), respectively. Meanwhile, the CLSM module uses a four-channel confocal fiber-coupled laser. Its emitted light propagates and diverges through the fiber, reaching the collimating lens (C1) and the aperture (Iris). After passing through the reflecting mirror (M2) and dichroic filter wheels (DMFilterWheel 1, DMFilterWheel 2), it merges with the OCT sample light. Then, after passing through the optical scanner and focusing lenses (L2, L3), it is finally focused onto the sample by the same objective lens. The sample excitation fluorescence (CLSM return light) is collected by the objective lens and returned along the same path. It is then separated into excitation and emission light by the dichroic mirror filter wheel (DMFilterWheel1). The sample excitation fluorescence passes through the filters (F1, F2), the focusing lens (L4), and the detection aperture. It is then separated by wavelength by the series dichroic mirrors and coupled to the multiplex photomultiplier tubes (PMTs) to form an optical slice signal (ConfocalSignal) and transmitted to the acquisition and control unit (CommonModule1).

[0031] In terms of timing control, the K-trigger and A-trigger signals built into the sweep frequency light source in SS-OCT are used to ensure the synchronization of wavenumber interval sampling of the interference spectrum and the movement of the scanning galvanometer, respectively. The control signal (ControlSignal) controls the scanning galvanometer (Galvo-Galvo Scanning control) based on the OCT's trigger signals (Clock & SweptSignal) to achieve precise scanning in the XY directions. Simultaneously, it can control the filter switching (MotorControl (FilterChanging)) of the dichroic mirror filter wheels (DMFilterWheel 1, DMFilterWheel 2) to achieve single / multi-channel acquisition of the CLSM module. The scanning strategy implements synchronous scanning and layered scanning. This allows CLSM to be suitable for high-resolution imaging of surfaces and subsurfaces, while OCT can compensate for its limitations in imaging deep, label-free structures. In multimodal mode, high-resolution fluorescence signals and deep structural information can be obtained simultaneously, achieving complementarity between lateral resolution and imaging depth.

[0032] The shown module 50 for simultaneous geometric-mechanical observation and coupled analysis of bio-ink is integrated with a rheometer based on the OCT and FM common optical path design. Figure 4 As shown, this technology enables simultaneous microscopic observation of hydrogel interfaces under rheological loading; supports spatiotemporal dynamic structural imaging coordinated with pressure loading; supports high-throughput spatiotemporal simultaneous observation of the geometry and mechanics of bio-inks and the acquisition of multidimensional physical quantities; and employs coupling analysis algorithms, namely, printability analysis based on bio-ink structural characterization parameters and coupling modeling analysis between the geometric and mechanical multidimensional physical quantities of bio-inks. Figure 4 As shown, the robot cooperative control module includes an OCT imaging module, a fluorescence microscopy imaging module, a rheometer module, and a high-throughput automated hardware support module.

[0033] First, based on a temperature-controlled shear-imaging collaborative platform, an aluminum nitride ceramic-based Peltier temperature control module (4-80℃, ±0.2℃) integrates a rheological fixture and an ultraviolet curing module, combined with a common optical path design for the OCT and fluorescence modules, to support synchronous rheological-structural observation. Second, a μs-level synchronous control network is constructed based on the EtherCAT bus, using an FPGA to implement time-series closed-loop control of the rheometer servo motor, OCT high-speed scanning galvanometer, data acquisition card (TTL trigger), and high-speed camera, employing a timestamp alignment algorithm to suppress timing jitter. Then, based on rheological data (normal force / torque / displacement signal), the OCT three-dimensional scanning area and the fluorescence microscope focusing depth are dynamically adjusted to ensure continuous tracking of the target microstructure. Finally, a clean-grade 6-axis robotic arm, based on a high-throughput automated hardware support module and a robot coordination control module, achieves fixed structure printing for synchronous structure-rheological observation, acquiring multi-dimensional physical quantity structural information corresponding to different structures for further bio-ink configuration-rheological coupling analysis.

[0034] High-throughput automation hardware support module 10, such as Figure 1 As shown, the system includes a clean-grade 6-axis robotic arm and modular working terminal, a material storage module and temperature control module 30, a multi-functional bio-ink cartridge workstation 20, and a Class 100 external environment control chamber 40, providing effective support and environmental protection for automated sample loading and high-throughput bio-ink structure-rheology detection. The automated movement and interaction of the clean-grade 6-axis robotic arm and modular working terminal ensure simultaneous observation of structure-rheology across scales. The modular working terminal is adaptable to bio-ink cartridges, supporting automated dispensing, transport, and 3D printing of cell bio-inks. The material storage module and temperature control module, including a liquid storage device and a temperature control device, primarily provide precise temperature-controlled storage for various bio-inks / cells. The multi-functional bio-ink cartridge workstation includes a low-temperature pneumatic extrusion cartridge, a low-temperature electric extrusion cartridge, a customized printhead library, an intelligent camera assembly, and an end-effector positioning and calibration module. The Class 100 external environment control chamber comprises three parts: a high-performance EBM variable frequency fan, wind speed / pressure / temperature and humidity sensors, and the overall mechanical structure and electrical peripherals. These provide the equipment system with a clean airflow environment characterized by wind pressure and positive pressure laminar flow, monitor the wind speed / pressure / temperature and humidity status within the clean system, and maintain a Class 100 clean environment. The high-throughput automation hardware support module serves as the core motion interaction module. The clean-grade 6-axis robotic arm system features a fully enclosed, particle-free design and nanometer-level positioning accuracy, supporting the contamination-free and precise operation of cell bio-inks. Specific processes include... Figure 5 As shown, Step 1: Ink loading. The bio-ink is manually mixed, loaded, and stored. Step 2: Mechanical transfer, the robotic arm retrieves the consumables tray; Step 3: Sample aliquoting and loading of aliquoted samples into the low-temperature sample library; Step 4: Sample grabbing. The robotic arm grabs the sample and loads it into the multi-functional ink cartridge workstation. Step 5: Automatic sample loading. The robotic arm and multi-functional ink cartridge workstation add samples into the rheological probe. Step 6: Rheological measurement, automatic sample scraping, rheology-photocuring-fluorescence detection; Step 7: Target printing. The robotic arm and multi-functional ink cartridge workstation print the target structure for the multi-scale three-dimensional high-resolution geometric imaging module. Step 8: Three-dimensional imaging, the cross-scale three-dimensional high-resolution geometric imaging module starts automatic pressure loading and measurement; Step 9: Mechanical transfer; the robotic arm returns the multi-functional ink cartridge workstation to its original position. Step 10: Rheological cleaning, automatic cleaning function activated; Step 11: Inspection and cleaning. The multi-scale 3D high-resolution geometric imaging module automatically cleans the sample, scrapes out the printed sample, and cleans the platform. Step 12: Coupling analysis. The server and control analysis modeling module output coupling detection data and reports.

[0035] The server and control analysis modeling module 70 supports efficient collaborative control and automated operation between modules, such as... Figure 1 As shown, it mainly includes a 50-module module for synchronous observation and coupling analysis of bio-ink geometry and mechanics, synchronous timing control and signal processing, a 10-module high-throughput automated hardware support module, a 6-axis robotic arm multi-module collaborative operation control, rheological-structural coupling analysis modeling, and tissue morphology-functional remodeling correlation analysis. It supports 3D printing of various cell bio-inks, synchronous timing control of geometric-mechanical observation, interferometric spectral signal processing and 3D reconstruction, quantitative visualization analysis of 3D structures, and bio-ink printability characterization. Machine learning-based multi-parameter coupling analysis technology supports cross-scale geometric-mechanical spatiotemporal dynamic coupling analysis modeling of bio-inks and nonlinear dynamic coupling analysis between tissue morphology and functional remodeling. Specific steps are as follows... Figure 6 As shown, Step 1: Data Acquisition. Acquire data from OCT, FM, and rheometer. Step 2: Data preprocessing, which involves cleaning, normalizing, and feature selection of the collected data. Step 3: Geometric-mechanical collaborative testing and analysis. Geometric testing and analysis includes the length, width, height, filament diameter, pore connectivity, volume, fluorescence, etc. of the printed model; mechanical testing and analysis includes the viscosity, storage modulus, strain, loss modulus, yield stress, etc. of the printed filament.

[0036] Step 4: Learning the geometry-mechanical coupling model based on graph learning, such as performing a graph learning model based on S samples on matrix data with feature dimensions at different time points to achieve M+N dimensional features.

[0037] After machine learning in step 5, performance evaluations such as mean squared error and coefficient of determination are obtained. Results analysis and interpretation are then performed, such as feature importance analysis and model interpretation techniques, and the final model is output.

[0038] The server and control analysis modeling module, based on automated multimodal data processing and analysis technology, analyzes the dynamic coupling mechanism of multidimensional structural and rheological parameters of bio-inks. Utilizing a cross-scale 3D high-resolution geometric imaging module, it acquires time-series data on the structural evolution of bio-inks during phase transitions and rheological response parameters (such as viscoelastic modulus and thixotropic index), constructing a dynamic database containing multidimensional structural features and rheological indices. Through a standardized preprocessing workflow, it achieves automatic alignment and noise filtering of multi-source heterogeneous data, and uses an adaptive feature selection algorithm to identify key parameter combinations affecting the configuration capabilities of bio-inks, reducing data redundancy. A nonlinear mapping model between multidimensional physical quantities is established to analyze the dynamic correlation between 3D structural evolution and macroscopic rheological behavior, and a cross-validation strategy is adopted to ensure the model's robustness under complex conditions. Furthermore, a parameter contribution quantification model is constructed to reveal the nonlinear relationship between multidimensional structural features and rheological behavior. Through feature importance analysis and model interpretation techniques, a comprehensive, accurate, and reliable bio-ink performance prediction model is built, revealing the intrinsic connection and interaction mechanism between the structural characterization parameters and rheological testing parameters of bio-inks, providing digital support for bio-ink screening.

[0039] The functional redesign test platform 80 shown is as follows: Figure 1 As shown, based on the multi-scale three-dimensional high-resolution geometric imaging module 60 or the bio-ink geometry-mechanics synchronous observation and coupling analysis module 50, bio-ink screening and tissue printing of different organoids, as well as tissue morphogenesis-functional remodeling correlation analysis, are realized. Highly reproducible and precise 3D printing of liver / intestinal tissue organoids and construction of physiological microenvironments are achieved, which are then used for drug testing and analysis. This completes the system's principle and application verification, and improves the system's performance parameters.

[0040] Example 2: This embodiment provides a further solution based on solution 1, see appendix. Figure 2 -Appendix Figure 4 As shown, the multi-scale three-dimensional high-resolution geometric imaging module uses a common optical path design to combine optical coherence tomography with fluorescence microscopy or confocal microscopy.

[0041] In this embodiment, a common optical path scheme for the OCT optical path and the CLSM optical path is used. See Appendix. Figure 3 As shown, the common optical path scheme in this embodiment includes a CLSM module, a common processing module connected to the CLSM module, an OCT module having a common optical path with the CLSM module, and a common optical path module used to focus the optical paths of the CLSM module and the OCT module onto the same sample.

[0042] A multimodal imaging system combining OCT and CLSM achieves focused optical path on the same sample through a shared optical path module, leveraging complementary technological advantages: CLSM captures the microstructure of fluorescently labeled cells at sub-micron lateral resolution, while OCT provides real-time dynamic monitoring of structural changes in the cell-based bio-ink and printed tissue. The shared optical path design ensures strict alignment of the scanning areas of both systems, reducing spatial registration errors and improving the completeness and accuracy of characterizing the microscopic details and macroscopic morphology of the bio-ink.

[0043] The co-processing module is a control terminal, which is a computer in this embodiment. The co-processing module is equipped with external auxiliary devices such as a data acquisition card.

[0044] The OCT module can use swept-frequency OCT (SS-OCT) based on a swept-frequency light source, or it can use spectral domain OCT (SD-OCT). In this embodiment, the solution is to use swept-frequency OCT (SS-OCT) based on a swept-frequency light source.

[0045] The OCT module includes a swept-frequency light source connected to the co-processing module. The swept-frequency light source is connected to fiber optic coupler 1. Fiber optic coupler 1 is connected to fiber optic circulator 1 and fiber optic circulator 2. Fiber optic circulator 2 is connected to a reference arm and fiber optic coupler 2. A polarization controller 2 is provided between fiber optic circulator 2 and fiber optic coupler 2. The swept-frequency light source is a near-infrared swept-frequency light source. Fiber optic coupler 1 is a 90 / 10 fiber optic coupler, and fiber optic coupler 2 is a 50 / 50 fiber optic coupler. The reference arm includes a reflector M1, a focusing lens L1, and a collimating lens C3 arranged sequentially.

[0046] The fiber optic circulator 1 is connected to the collimating lens C2 and the fiber optic coupler 2 respectively. A polarization controller 1 is provided between the fiber optic circulator 1 and the fiber optic coupler 2. The fiber optic coupler 2 is connected to a balanced photodetector, which is connected to the coprocessing module.

[0047] The CLSM module includes a laser controller connected to the co-processing module. The laser controller is connected to a 4-channel confocal fiber-coupled laser. Each 4-channel confocal fiber-coupled laser is equipped with a collimating lens C1. A reflecting mirror M2 is positioned on one side of the collimating lens C1. An aperture is positioned between the collimating lens C1 and the reflecting mirror M2. A dichroic mirror filter wheel is positioned on one side of the reflecting mirror M2. A 4-channel photomultiplier tube connected to the co-processing module is positioned on one side of the dichroic mirror filter wheel. Filters F1 and F2, and a focusing lens L4 are arranged sequentially between the dichroic mirror filter wheel and the 4-channel photomultiplier tube. A probe aperture is positioned between the 4-channel photomultiplier tube and the focusing lens L4.

[0048] The common optical path module includes a dichroic mirror filter wheel, a high-speed scanning galvanometer is provided on one side of the dichroic mirror filter wheel, a sample is provided on one side of the high-speed scanning galvanometer, and a focusing lens L2, a focusing lens L3, and an objective lens are arranged sequentially between the high-speed scanning galvanometer and the sample.

[0049] The optical paths of the CLSM module and the OCT module are as follows: A near-infrared swept-frequency light source is used. After being split by a 90 / 10 fiber coupler, the light is then emitted as sample light and reference light through fiber circulators (CIR1, CIR2) and polarization controllers (PC1, PC2), respectively. Simultaneously, the CLSM module uses a four-channel confocal fiber-coupled laser. Its emitted light propagates and diverges through the fiber, reaching the collimating lens C1 and the aperture. After passing through the reflecting mirror M2 and the dichroic mirror filter wheel, it merges with the OCT sample light. After passing through the scanning galvanometer and focusing lenses (L2, L3), it is finally focused onto the sample by the same objective lens. The sample excitation fluorescence (CLSM return light) is collected by the scanning lens, returns along the same path, and is separated from the emitted light by the dichroic mirror filter wheel. The sample excitation fluorescence passes through filters (F1, F2), the focusing lens (L4), and the probe aperture, and is then separated by wavelength by a series of dichroic mirrors and coupled to multiple photomultiplier tubes (PMTs) to form optical slice signals, which are then transmitted to the acquisition and control unit.

[0050] Example 3: This embodiment provides a further solution based on solution 1, see appendix. Figure 2 - Appendix Figure 4 As shown, the multi-scale three-dimensional high-resolution geometric imaging module uses a common optical path design to combine optical coherence tomography with fluorescence microscopy or confocal microscopy.

[0051] In this embodiment, a common optical path scheme for the OCT optical path and the FM optical path is used. See Appendix. Figure 2 As shown, the common optical path scheme in this embodiment includes an FM module, a common processing module connected to the FM module, an OCT module having a common optical path with the FM module, and a common optical path module used to focus the optical paths of the FM module and the OCT module onto the same sample.

[0052] The OCT and FM combined optical path scheme uses OCT to monitor the structural changes of cell bio-ink and printed tissue in real time; and uses FM to monitor tracers, proliferation markers and other specifically labeled target molecules to accurately capture the spatial localization, metabolic activity and functional phenotype information of cells, so as to achieve quantitative characterization of key parameters such as cell viability and proliferation kinetics.

[0053] The OCT module can use swept-frequency OCT (SS-OCT) based on a swept-frequency light source, or it can use spectral domain OCT (SD-OCT). In this embodiment, the solution is to use swept-frequency OCT (SS-OCT) based on a swept-frequency light source.

[0054] The OCT module includes a swept-frequency light source connected to the co-processing module. The swept-frequency light source is connected to fiber optic coupler 1. Fiber optic coupler 1 is connected to fiber optic circulator 1 and fiber optic circulator 2. Fiber optic circulator 2 is connected to a reference arm and fiber optic coupler 2. The reference arm includes a reflector M1, a focusing lens L1, and a collimating lens C3 arranged sequentially. A polarization controller 2 is provided between fiber optic circulator 2 and fiber optic coupler 2. The swept-frequency light source is a near-infrared swept-frequency light source. Fiber optic coupler 1 is a 90 / 10 fiber optic coupler, and fiber optic coupler 2 is a 50 / 50 fiber optic coupler.

[0055] The fiber optic circulator 1 is connected to a collimating lens C1 and a fiber optic coupler 2. A polarization controller 1 is provided between the fiber optic circulator 1 and the fiber optic coupler 2. The fiber optic coupler 2 is connected to a balanced photodetector, which is connected to the coprocessing module.

[0056] The FM module includes an excitation source connected to the co-processing module. A filter F1 is located on one side of the excitation source. A filter switching wheel is located on one side of the filter F1. A dichroic mirror DM2, corresponding to the positions of filter F1 and collimating lens C1, is located inside the filter switching wheel. The filter switching wheel is connected to the co-processing module. A dichroic mirror DM1 is located on one side of the filter switching wheel. A scanning galvanometer and filter F2 are located on one side of the dichroic mirror DM1. A reflecting mirror M2 is located on one side of the filter F2. A detection camera is located on one side of the reflecting mirror M2. The detection camera is connected to the co-processing module. A beam splitter BS is located between the reflecting mirror M2 and the detection camera. An eyepiece is located on one side of the beam splitter BS.

[0057] In this embodiment, the common optical path module includes a scanning galvanometer, a sample is placed on one side of the scanning galvanometer, and a focusing lens L2, a focusing lens L3, and an objective lens are arranged sequentially between the scanning galvanometer and the sample. The scanning galvanometer is connected to the common processing module.

[0058] The optical paths of the FM module and the OCT module are as follows: The OCT module integrates the two modules to achieve cross-scale (micrometer-millimeter) dual-modal dynamic imaging of macroscopic three-dimensional morphology and microscopic cell distribution / activity. The OCT module can employ swept-frequency OCT (SS-OCT) based on a swept-frequency light source, or spectral-domain OCT (SD-OCT). Taking SS-OCT as an example, a near-infrared swept-frequency light source (SS) is used. After being split by a 90 / 10 fiber coupler (FC1), the light is then emitted as sample light and reference light via fiber circulators (CIR1, CIR2) and polarization controllers (PC1, PC2), respectively. Simultaneously, the FM module, connected to the co-processing module, shares a common optical path module with the FM module, used to focus the optical paths of the FM and OCT modules onto the same sample.

[0059] Definitions: OCT: Optical Coherence Tomography; Utilizing the principle of low-coherence optical interferometry, the microstructure of biological tissues can be reconstructed by measuring the interference signal between the backscattered light from the sample and the reference light. It features micrometer-level resolution and millimeter-level penetration depth, enabling real-time, non-invasive imaging without the need for fluorescent labeling.

[0060] CLSM: Confocal Laser Scanning Microscopy; Point light source illumination is used, and scattered light outside the focal plane is eliminated by a pinhole filter. The sample is scanned point by point to form a high-resolution fluorescence image. The lateral resolution can reach 0.2 μm, and the axial resolution is about 0.5 μm, supporting three-dimensional tomographic imaging.

[0061] FM: Fluorescence Microscopy; By utilizing the property of fluorescent substances to emit long-wavelength fluorescence after absorbing excitation light, fluorescent markers in samples can be observed through specific filters, which can be used for the detection of cell structure, protein distribution, etc.

[0062] PC stands for polarization controller, PC1 stands for polarization controller 1, and PC2 stands for polarization controller 2; FC stands for fiber optic coupler, FC1 stands for fiber optic coupler 1, and FC2 stands for fiber optic coupler 2. CIR stands for fiber optic circulator, CIR1 stands for fiber optic circulator 1, and CIR2 stands for fiber optic circulator 2; PMT stands for multi-channel photomultiplier tube. FPGA stands for Field Programmable Gate Array. In this embodiment, "sample" and "sample" have the same meaning. "Scanning galvanometer" and "high-speed scanning galvanometer" have the same meaning. The co-processing module 10 is the control terminal, which in this embodiment is a computer. The co-processing module is equipped with external auxiliary devices such as a data acquisition card.

[0063] It should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0064] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0065] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A multi-scale structure-material rheology testing system, characterized in that, include, A multi-scale 3D high-resolution geometric imaging module is used to achieve imaging and detection of printed models; The module for simultaneous observation and coupling analysis of the geometry and mechanics of bio-ink is used to realize simultaneous microscopic observation of hydrogel interfaces under rheological loading. High-throughput automation hardware support module, used to provide the loading platform; The server and control analysis modeling module is used to analyze the dynamic coupling mechanism of the structure-rheological multidimensional parameters of bio-ink; The functional remodeling testing platform is used for screening bio-inks for different organoids and for tissue printing, as well as for correlation analysis of tissue morphogenesis and functional remodeling.

2. The multi-scale structure-material rheology testing system according to claim 1, characterized in that, The multi-scale three-dimensional high-resolution geometric imaging module has a common optical path, which is a combination of optical coherence tomography and fluorescence microscopy or a combination of optical coherence tomography and confocal microscopy.

3. The multi-scale structure-material rheology testing system according to claim 2, characterized in that, The common optical path is a combined optical path for optical coherence tomography and fluorescence microscopy, including an FM module, a co-processing module connected to the FM module, and an OCT module that shares a common optical path with the FM module. This common optical path module is used to focus the optical paths of the FM module and the OCT module onto the same sample.

4. The multi-scale structure-material rheology testing system according to claim 2, characterized in that, The common optical path is a combined optical path for optical coherence tomography and confocal microscopy, including a CLSM module, a coprocessing module connected to the CLSM module, an OCT module with a common optical path to the CLSM module, and a common optical path module used to focus the optical paths of the CLSM module and the OCT module onto the same sample.

5. The multi-scale structure-material rheology testing system according to claim 1, characterized in that, In terms of timing control of the multi-scale three-dimensional high-resolution geometric imaging module, a high-precision synchronous triggering module controlled by FPGA is adopted to generate pulse signals with strict timing alignment, which synchronously drive OCT signal acquisition and fluorescence camera exposure, ensuring timing synchronous triggering and real-time synchronous storage of multi-channel data. Alternatively, the K-trigger and A-trigger signals of the OCT light source are used to ensure the synchronous sampling of wavenumber intervals of interference spectrum and the movement of scanning galvanometer, respectively.

6. The multi-scale structure-material rheology testing system according to claim 2, characterized in that, The bio-ink geometry-mechanical synchronous observation and coupling analysis module includes an OCT module, an FM module, a rheometer module, and a robot collaborative control module with high-throughput automated hardware support.

7. The multi-scale structure-material rheology testing system according to claim 1, characterized in that, The high-throughput automated hardware support module includes a clean-grade 6-axis robotic arm and modular work terminal, a material storage module and temperature control module, a multi-functional bio-ink cartridge workstation, and a Class 100 external environment control chamber.

8. The multi-scale structure-material rheology testing system according to claim 1, characterized in that, The server and control analysis modeling module support efficient collaborative control and automated operation among various modules, including synchronous timing control and signal processing of the bio-ink geometry-mechanical synchronous observation and coupling analysis module, high-throughput automated hardware support module 6-axis robotic arm multi-module collaborative operation control, rheological-structural coupling analysis modeling, and tissue morphology-functional remodeling correlation analysis.

9. A multi-scale structure-material rheology testing system according to any one of claims 1-8, characterized in that, The server and control analysis modeling module are capable of machine learning, and the learning steps are as follows: Step 1), Data acquisition, acquiring data from the common optical path of optical coherence tomography and fluorescence microscopy, as well as data from the rheometer; Step 2), data preprocessing, which involves cleaning, normalizing, and feature selection of the collected data; Step 3), perform geometry-mechanism co-test analysis; Step 4), learning the geometry-mechanics coupling model based on graph learning; Step 5) After performing machine learning, a performance evaluation is obtained, the results are analyzed and interpreted, and the final model is output.

10. The multi-scale structure-material rheology testing system according to claim 1, characterized in that, The server and control analysis modeling module rely on the cross-scale three-dimensional high-resolution geometric imaging module to obtain the time series data of structural evolution and rheological response parameters of bio-ink during the phase transition process, and construct a dynamic database containing multi-dimensional structural features and rheological indices.

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