Self-developing vascular casting agent and preparation method thereof

Abstract

The invention belongs to the technical field of experiments and the field of anatomical research, and particularly relates to a self-developing vascular casting agent and a preparation method thereof. The invention discloses a preparation method of a self-developing vascular casting agent. The self-developing vascular casting agent is obtained by uniformly mixing iopromide, natural latex, II-type barium sulfate and pigment, wherein in parts by weight, the iopromide accounts for 30-40%; 25%-30% of natural latex; 40% of type II barium sulfate; and 5%-10% of pigment. The blood vessel casting agent developed by the invention is excellent in formula flowability (smooth perfusion), does not cause blockage, can avoid reverse osmosis of a capillary microenvironment, and realizes arteriovenous differentiated perfusion; and meanwhile, high-contrast development is realized, and complete coverage of capillary vessels is basically realized. The optimized blood vessel casting agent formula is completely cured (at room temperature) within 24 hours, the shrinkage rate is low, and blood vessel deformation is avoided.

Description

Technical Field

[0001] This invention belongs to the fields of experimental technology and anatomical research, specifically relating to a self-illuminating vascular casting agent and its preparation method. Background Technology

[0002] As an important tool for anatomical research, the development of vascular casting technology has long been limited by the inherent defects of perfusion materials. While current mainstream vascular casting agents (such as methacrylic acid resin, epoxy resin, polyurethane, and modified gelatin preparations) perform well in terms of tissue support and morphological preservation, they have significant shortcomings in practical applications: First, the viscosity coefficient of existing perfusion fluids is generally low, making it easy to form reverse connections between arteriovenous lumens through capillary networks during perfusion. This results in structural mixing of arterial and venous systems in the final casting product, and this uncontrollable luminal communication phenomenon seriously hinders the independent morphological study of the vascular system. Second, conventional casting agents lack X-ray attenuation coefficient adjustment functions (such as iodine-based or heavy metal element loading), resulting in ineffective contrast imaging in CT images. This material limitation not only deprives important data sources for three-dimensional image reconstruction but also makes it difficult to accurately resolve the spatial conformation of blood vessels and their positioning relationship with adjacent tissues.

[0003] Although recent studies have attempted to achieve arteriovenous typing using two-color perfusion or gradient viscosity control, these methods suffer from low operational tolerance and stringent perfusion pressure control. Furthermore, modifications involving the addition of contrast agents often alter the physicochemical properties of the perfusion fluid, leading to localized fractures or artifacts in the vascular cast. These include: 1. Physicochemical instability: Contrast agents (such as barium sulfate and iodine compounds) increase the viscosity of the perfusion fluid, interfering with flowability and causing incomplete microvascular filling or residual air bubbles; they may also damage the polymer cross-linking structure, resulting in uneven local curing; 2. Decreased interfacial compatibility: The weak bonding between contrasting particles and the resin matrix makes them prone to peeling under corrosion or thermal stress, forming artifacts (such as white spots on the cast surface) or cracks. These technical bottlenecks severely restrict the in-depth application of vascular casts in microcirculation mechanism research and image-guided surgery. Summary of the Invention

[0004] In view of the problems existing in existing vascular casting agents, the purpose of this invention is to develop a novel vascular casting agent that can distinguish between arteries and veins during perfusion, can be clearly distinguished during dissection, can be subjected to CT or X-ray imaging scans after perfusion, and has excellent imaging effect.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The first aspect of this invention discloses a method for preparing an autoradiographic vascular casting agent, which involves uniformly mixing iopromium, natural latex, type II barium sulfate, and pigment. Of which, by weight, iopromide: 30%~40%; Natural latex: 25%~30%; Type II barium sulfate: 40%; Pigment: 5%~10%.

[0006] The concentration of iopromium in the vascular casting agent is 200-400 mg / mL.

[0007] Preferably, the concentration of iopromium in the vascular casting agent is 300 mg / mL.

[0008] The natural rubber latex contains 50-70% natural rubber hydrocarbons.

[0009] Preferably, the concentration of natural rubber hydrocarbons in the natural latex is 60%.

[0010] The pigment is a water-based pigment.

[0011] The mixing includes ultrasonic mixing or stirring mixing, and the mixing time is 15 to 30 minutes.

[0012] The second aspect of this invention discloses a self-illuminating vascular casting agent, which is prepared by the above-described preparation method.

[0013] The third aspect of this invention discloses the application of the above-mentioned self-illuminating vascular casting agent in the fields of microcirculation mechanism research and image-guided surgery.

[0014] Compared with the prior art, the present invention has the following advantages: 1. Traditional vascular casting agents (such as resin and gelatin) have low viscosity, which easily leads to arterial and venous mixing through capillary networks, making independent study impossible. Traditional contrast agents (such as barium sulfate) tend to aggregate, resulting in incomplete filling or blurred imaging of small vessels. The vascular casting agent formulation developed in this invention has excellent flowability (smooth perfusion), does not cause blockage, avoids reverse permeation of the capillary microenvironment, and achieves arterial and venous differentiation perfusion; at the same time, it achieves high-contrast imaging, with near-complete coverage of microvessels.

[0015] 2. Adding contrast agents often leads to uneven curing or interface peeling (such as mold breakage, white spot artifacts); the optimized vascular casting agent formula of this invention cures completely within 24 hours (at room temperature), has a low shrinkage rate, and avoids vascular deformation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or existing methods and experiments, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 Images obtained by CT imaging of mouse head samples after perfusion with the perfusion solutions prepared in Example 1 and Comparative Examples 1-2.

[0018] Figure 2 CT imaging (cerebral arteries) was performed after perfusion of mouse head samples with the perfusion solution prepared in Example 1.

[0019] Figure 3 Anatomical diagram of mouse brain after perfusion using the perfusion solution formulation of Example 1. Detailed Implementation

[0020] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments, but this does not limit the present invention to the scope of the described embodiments. Experimental methods and techniques in the following embodiments that do not specify specific conditions are generally performed according to conventional conditions in the relevant art or according to the conditions recommended by the manufacturer.

[0021] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0022] Experimental materials: Natural latex: Shenzhen Yoshida Chemical Co., Ltd., model H0101. Pigment: Marie's acrylic pigment.

[0023] Example 1 The experimental procedure for vascular perfusion was as follows: male 8-week-old C57BL / 6 mice were injected intramuscularly with 70 mg / kg of salbutamol and intravenously with 3000 U / mL of heparin sodium via the tail vein.

[0024] The mouse neck was prepared with a longitudinal incision along the midline of the neck to fully expose the neck tissue. The submandibular and sublingual glands were separated, and the right external jugular vein, right common carotid artery, left external jugular vein, and left common carotid artery were also separated and exposed. The proximal ends of these arteries and veins were ligated using 8-0 sutures, and an 8-0 ligature was left distally at the right external jugular vein and left common carotid artery. A cannula was inserted into the left common carotid artery, and the reserved ligatures were tied to secure the cannula. A small incision was made anterior to the proximal ligature of the right external jugular vein. Physiological saline was infused into the cannula of the left common carotid artery. After the outflow from the right external jugular vein changed from turbid to clear, the perfusion solution of this invention (by weight, iopromide: 30%, natural latex: 25%, barium sulfate type II: 40%, pigment: 5%, wherein the concentration of iopromide is 300 mg / mL) was slowly injected, and infusion was stopped when significant resistance was felt during injection. The perfused specimens were fixed in a fixative (neutral buffered formalin).

[0025] Comparative Example 1 The experimental procedure for vascular perfusion was as follows: male 8-week-old C57BL / 6 mice were injected intramuscularly with 70 mg / kg of salbutamol and intravenously with 3000 U / mL of heparin sodium via the tail vein.

[0026] The mouse neck was prepared with a longitudinal incision along the midline of the neck to fully expose the neck tissue. The submandibular and sublingual glands were separated, and the right external jugular vein, right common carotid artery, left external jugular vein, and left common carotid artery were also separated and exposed. The proximal ends of these arteries and veins were ligated using 8-0 sutures, and an 8-0 ligature was left distally at the right external jugular vein and left common carotid artery. A cannula was inserted into the left common carotid artery, and the reserved ligatures were tied to secure the cannula. A small incision was made anterior to the proximal ligature of the right external jugular vein. Physiological saline was infused into the cannula of the left common carotid artery. After the outflow from the right external jugular vein changed from turbid to clear, the perfusion solution prepared in Comparative Example 1 (by weight, iopromide: 47.5%, natural latex: 47.5%, pigment: 5%, with iopromide concentration of 300 mg / mL) was slowly injected into the cannula. Infusion was stopped when significant resistance was felt during injection. The perfused specimens were then fixed in a fixative.

[0027] Conclusion: As a water-soluble contrast agent, iopromide mainly relies on blood flow distribution. When used in combination with natural latex, it cannot achieve good vascular imaging.

[0028] Comparative Example 2 The experimental procedure for vascular perfusion was as follows: male 8-week-old C57BL / 6 mice were injected intramuscularly with 70 mg / kg of salbutamol and intravenously with 3000 U / mL of heparin sodium via the tail vein.

[0029] The mouse neck was prepared with a longitudinal incision along the midline to fully expose the neck tissue. The submandibular and sublingual glands were separated, and the right external jugular vein, right common carotid artery, left external jugular vein, and left common carotid artery were also separated and exposed. The proximal ends of these arteries and veins were ligated using 8-0 sutures, and an 8-0 ligature was left distally at the right external jugular vein and left common carotid artery. A cannula was inserted into the left common carotid artery, and the reserved ligatures were tied to secure the cannula. A small incision was made anterior to the proximal ligature of the right external jugular vein. Physiological saline was infused into the cannula of the left common carotid artery. After the outflow from the right external jugular vein changed from turbid to clear, the perfusion solution from Comparative Example 2 (by weight: natural latex: 41%, barium sulfate type II: 54%, pigment: 5%, with iopromide concentration of 300 mg / mL) was infused into the cannula slowly. Perfusion was stopped when significant resistance was felt during injection. The perfused specimen was then fixed in a fixative.

[0030] In Comparative Example 2, barium sulfate forms aggregates after being prepared into a suspension. Higher concentrations result in larger aggregates, preventing it from penetrating finer blood vessels and thus hindering imaging of small vessels. Lower concentrations produce smaller aggregates, allowing it to enter finer blood vessels, but the low concentration is insufficient to completely block X-rays, leading to unclear imaging. Therefore, to ensure the fluidity of the perfusion solution and imaging quality, Comparative Example 2 used a natural latex to type II barium sulfate weight ratio of 3:4.

[0031] Example 2. CT Imaging 1. Equipment: Sanying Precision NanoVoxel-2000 2. Reconstruction software: VoxelStudio Recon 3. Analysis software: CT Vox 4. Sample scanning parameters: Radiation source voltage: 85 KV; Radiation source current: 100 μA; Scanning frame rate: 360°, 720 frames, 0.5° / frame; Scanning resolution: VoxelDis = 9.99 μm.

[0032] 5. Sample scanning and reconstruction The samples prepared in Example 1 and Comparative Examples 1-2 were placed on a scanning frame and subjected to CT scans. After the scans were completed, the heads were reconstructed using reconstruction and analysis software. The results are as follows: Figure 1-2 As shown.

[0033] By comparison, the vascular images formed after perfusion with the perfusion solution of the present invention can clearly show microvascular branches, and no venous leakage was observed in the arterial perfusion solution. Figure 1The arteriovenous casts showed clear boundaries and better angiography results (compared to Comparative Examples 1 and 2). Experimental results: Comparative Example 1 (without barium sulfate): main trunk was visualized, but branches were missing. Comparative Example 2 (without iodopromide): microvascular visualization was discontinuous (due to incomplete filling caused by barium sulfate aggregation).

[0034] Figure 2 (Example 1) A complete vascular network (such as the cerebral arterial tree) from the main artery to the tiny branches is clearly presented without any breaks or artifacts, indicating that the perfusion fluid has good fluidity and can fully fill the microvessels.

[0035] Example 3: Detailed Dissection After the scan was completed, the skull of the mouse after perfusion in Example 1 was opened, the brain was removed and photographed, and the results are as follows. Figure 3 As shown, the vascular cast of the mouse brain after treatment with the perfusion solution prepared in Example 1 of this invention is intact, and no vascular rupture has occurred, which is consistent with the CT imaging results, indicating that the formulation has both imaging stability and structural support.

[0036] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall also fall within the protection scope of the present invention.

Claims

1. A method for preparing a self-developing vascular casting agent, characterized by, The product is obtained by mixing iodopromium, natural latex, barium sulfate type II and pigment evenly. Of which, by weight, iopromide: 30%~40%; Natural latex: 25%~30%; Type II barium sulfate: 40%; Pigment: 5%~10%.

2. The production method according to claim 1, characterized by, The concentration of iopromium in the vascular casting agent is 200-400 mg / mL.

3. The production method according to claim 2, characterized by, The concentration of iopromium in the vascular casting agent is 300 mg / mL.

4. The preparation method according to claim 1, characterized in that, The natural rubber latex has a natural rubber hydrocarbon concentration of 50-70%.

5. The preparation method according to claim 4, characterized in that, The natural rubber latex has a natural rubber hydrocarbon concentration of 60%.

6. The preparation method according to claim 1, characterized in that, The pigment is a water-based pigment.

7. The preparation method according to claim 1, characterized in that, The mixing includes ultrasonic mixing or stirring mixing, and the mixing time is 15 to 30 minutes.

8. A self-illuminating vascular casting agent, characterized in that, It is prepared by the preparation method according to any one of claims 1-7.

9. The application of the self-illuminating vascular casting agent as described in claim 8 in the field of microcirculation mechanism research and image-guided surgery.

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