CN113499483B

CN113499483B - Nano copper sulfide coating modified memory alloy esophageal stent and preparation method thereof

Info

Publication number: CN113499483B
Application number: CN202110721642.0A
Authority: CN
Inventors: 张璇; 吴颖; 苏礼超; 宋继彬
Original assignee: Fuzhou University
Current assignee: Fuzhou University
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2022-05-24
Anticipated expiration: 2041-06-28
Also published as: CN113499483A

Abstract

The invention belongs to the technical field of medical instruments, and relates to a memory alloy esophageal stent with a uniform nano copper sulfide film and a preparation method thereof, wherein the memory alloy esophageal stent has a high-efficiency photothermal physiotherapy function and is prepared by reducing dopamine under an alkaline condition to obtain a polydopamine-coated memory alloy stent and then adsorbing copper ions by the polydopamine efficiently to grow copper sulfide in situ under a heating condition. The method adopts a unique method for in-situ growth of the nano CuS particles on the surface of the stent, the nano CuS material is safe and nontoxic, and the growth process is simple and quick; the photo-thermal conversion is efficient, and can be repeatedly used for many times; the invention can be used for nickel-titanium alloy stents of various shapes and other types, such as biliary stents, intestinal stents, urinary tract stents and tracheal stents.

Description

Nano copper sulfide coating modified memory alloy esophageal stent and preparation method thereof

Technical Field

The invention belongs to the field of biomedical equipment, and particularly relates to a memory alloy esophageal stent modified by a nano copper sulfide coating and a preparation method thereof, which can be used for photothermal therapy of esophageal cancer under near-infrared laser irradiation.

Background

Esophageal cancer is the lethal factor of the sixth-largest cancer in the world. As a country with high incidence of esophageal cancer, the incidence rate of esophageal cancer is about 20-30 times higher than that of countries in Europe and America, and the cancer is the fourth death rate in China. Surgery and chemoradiotherapy are three clinical means for treating esophageal cancer, however, 60% of esophageal cancer patients are in middle and advanced stages of cancer at the time of visiting a doctor and basically lose the chance of surgical treatment, and the patients in the advanced stages often cannot bear systemic chemotherapy and radiotherapy with high side effects due to weakness. Some patients with esophageal cancer are not sensitive to radiotherapy, and show low treatment effect due to radiotherapy tolerance. In addition, long-term nutrient intake disorder caused by dysphagia caused by malignant stenosis caused by invasive growth of esophageal cancer is easy to cause complications such as hypoproteinemia and electrolyte flocculation for patients, the life quality is extremely low, and the treatment prognosis is poor. Therefore, when the esophageal stenosis of a patient is solved, aiming at the patient who can not carry out operation chemoradiotherapy, the novel photothermal treatment mode is used for improving the basic symptoms of the patient, improving the life quality of the patient, prolonging the life of the patient and maintaining the follow-up life. Photothermal therapy (PTT), an emerging cancer treatment, has the advantages of precise control, noninvasive penetration, and low toxicity to normal tissues, compared to other treatments.

Endoscopic esophageal stent placement is the simplest and effective palliative treatment method for solving the problem of eating difficulty at present. However, the current self-expandable stent used clinically can only treat esophageal stenosis by relying on physical expansion, cannot treat tumors, and cannot fundamentally solve the problem of restenosis caused by tumor regrowth. Therefore, the multifunctional stent which can physically support the malignant lesion in the lumen and can efficiently convert photothermal to improve the treatment effect is important for improving the survival condition of the patient.

Disclosure of Invention

Aiming at the problems, the invention provides a memory alloy esophageal stent modified by a nano copper sulfide coating and a preparation method thereof.

In order to achieve the purpose, the invention is realized by the following technical scheme:

a memory alloy esophageal stent modified by a nano copper sulfide coating comprises a stent and is characterized in that a layer of nano copper sulfide particles is uniformly covered on the surface of the stent.

The stent is a columnar latticed stent woven by nickel-titanium alloy wires, the diameter of the stent is about 16-20mm, the length of the stent is 50-120mm, the supporting force is 60-80g/mm, and the stent is a common standard (NT-SMA) approved for clinical use.

Furthermore, the particle size of the nano copper sulfide particles is 50-150 nm.

Further, the preparation method of the memory alloy esophageal stent modified by the nano copper sulfide coating comprises the following steps:

reducing dopamine under an alkaline condition to obtain a polydopamine-coated memory alloy stent, and then efficiently adsorbing copper ions by the polydopamine to grow copper sulfide in situ under a heating condition to obtain the memory alloy esophageal stent modified by the nano copper sulfide coating.

The preparation method of the memory alloy esophageal stent modified by the nano copper sulfide coating specifically comprises the following steps:

1) preparing a dopamine-coated nickel-titanium stent: cleaning a nickel-titanium alloy stent, immersing the nickel-titanium alloy stent in 1-15mM Tris-HCl or Tris-buffer solution, adding dopamine into the solution to enable the final solubility of the dopamine to be 1-10mg/mL, stirring for 8-15 hours in a dark place, taking out the stent, and cleaning the polydopamine coated stent for 3-5 times by using deionized water to completely remove non-adsorbed polydopamine particles;

2) immersing the polydopamine-coated stent in 400mL of 0.5-5mg/mL PVA solution, stirring at 1000rpm for 10-40min, and then adding 500mg of CuSO 100₄·5H₂O and 50-150mg Na₂S₂O₃·5H₂Adding O into the PVA solution to obtain a green colloidal solution;

3) and heating the mixed solution to 60-90 ℃ and keeping the temperature for 2h, naturally cooling to room temperature after the reaction is finished, taking out the product, cleaning and drying to obtain the memory alloy stent covered with the CuS nano-particles.

Further, the pH of the Tris-HCl or Tris-buffer in the step 1) is 8.5.

Further, the product in the step 3) is taken out and then is washed with deionized water for three times.

Further, in the step 3), the drying temperature is 60 ℃, and the drying time is 3-5 h.

The memory alloy esophageal stent modified by the nano copper sulfide coating can be applied to photo-thermal treatment of cancers.

Compared with the prior art, the invention has the following beneficial effects:

1) by adopting a unique in-situ nano copper sulfide particle growth technology, the nano copper sulfide material has stable property, is not easy to decompose, is safe and nontoxic, and has simple and rapid growth process.

2) Different from the radiotherapy stent and the drug eluting stent which are clinically marketed at present, the stent utilizes the efficient photothermal conversion effect of the nano copper sulfide, improves the cancer treatment precision and the treatment effect, and can carry out accurate and noninvasive efficient treatment on esophageal tumors. The material is safe, the photothermal conversion effect is good, the material preparation process is simple, the material can be repeatedly used, and the treatment process is simple and convenient.

3) The method for in-situ growth of the nano copper sulfide film can be used for nickel-titanium alloy stents with various shapes and types, such as biliary stents, intestinal stents, urinary tract stents, tracheal stents and the like.

4) The in-situ grown nano copper sulfide scaffold can be subjected to repeated near-infrared laser irradiation for multiple times, and a stable photothermal conversion effect is kept (fig. 8).

5) The prepared nickel-titanium alloy wire covered by the in-situ grown nano copper sulfide film can be used for nickel-titanium alloy stents of all types and sizes, and has the advantages of high preparation speed and simple method.

Drawings

FIG. 1 is a scanning electron microscope image of a nickel titanium stent wire grown with untreated nano copper sulfide particles;

FIG. 2 is a scanning electron microscope image of a nickel titanium stent wire covered with nano copper sulfide;

FIG. 3 is an enlarged scanning electron microscope image of a nickel titanium stent coated with nano copper sulfide particles;

FIG. 4 is an elemental scan of a scanning electron microscope of a nickel titanium stent wire coated with nano copper sulfide particles;

FIG. 5 is a scanning electron microscope image of a nickel titanium stent wire after nano copper sulfide particle sputtering;

FIG. 6 is a scanning electron microscope image of a nickel titanium stent wire covered with copper sulfide particles after multiple laser irradiations;

FIG. 7 is a graph of the temperature change of copper sulfide particle coated nickel titanium stent filaments after near infrared laser irradiation;

FIG. 8 is a graph of the temperature change of copper sulfide particle coated nickel titanium stent filaments under multiple irradiation with a near infrared laser;

FIG. 9 is a graph of dead and live double staining of cancer cells after different treatments. (live cells: green; dead cells: red)

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.

For further disclosure, but not limitation, the present invention is further described in detail below with reference to examples.

Example 1

A preparation method for growing copper sulfide nano particles on a nickel-titanium alloy wire in situ comprises the following steps:

1) preparing a dopamine-coated nickel-titanium stent: after first surface-washing the nitinol stent, the stent was immersed in 8mM Tris-HCl buffer (pH 8.5). Adding dopamine into the solution to enable the final solubility of the dopamine to be 2mg/mL, and quickly stirring for 8 hours in a dark place; and taking out the stent, and washing the polydopamine coating stent by using deionized water for three times.

2) The dopamine coated stent was immersed in a beaker containing 400mL of 0.5mg/mL PVA solution, stirred at 1000rpm for 20min and then 150mg of CuSO was added ₄·5H₂O and 75mg Na₂S₂O₃·5H₂O was added to the PVA solution to give a green colloidal solution.

3) The mixture was then heated to 80 ℃ for 2 h. And after the reaction is finished, naturally cooling the reaction product to room temperature, taking out the product, washing the product with deionized water for three times, and then drying the product in an oven at 60 ℃ for 3 hours to obtain the CuS-coated stent.

Example 2

1) preparing a dopamine-coated nickel-titanium stent: firstly, cleaning the surface of a nickel-titanium alloy stent, immersing the stent in 10mM Tris-HCl buffer solution (pH 8.5), adding dopamine into the solution to enable the final solubility to be 5mg/mL, and quickly stirring for 12 hours in a dark place; and taking out the stent, and washing the polydopamine coating stent by using deionized water for three times.

2) The dopamine-coated stent was immersed in a beaker containing 400mL of 3mg/mL PVA solution, stirred at 1000rpm for 30min, and then 300mg of CuSO was added₄·5H₂O and 150mg Na₂S₂O₃·5H₂O was added to the PVA solution to give a green colloidal solution.

3) The mixture was then heated to 80 ℃ for 2 h. After the reaction was completed, it was allowed to cool to room temperature. The product was taken out and rinsed three times with deionized water, and then the product was dried in an oven at 50 ℃ for 3h to obtain a CuS-coated stent.

Example 3

A preparation method for growing copper sulfide nanoparticles on a nickel-titanium alloy wire in situ comprises the following steps:

1) preparing a dopamine-coated nickel-titanium stent: after first surface-washing the nitinol stent, the stent was immersed in 10mM Tris-HCl buffer (pH 8.5). Dopamine was added to the solution to a final solubility of 5 mg/mL. Quickly stirring for 8h in a dark place; and taking out the stent, and washing the polydopamine coating stent by using deionized water for three times.

2) The dopamine coated stent was immersed in a beaker containing 400mL of 5mg/mL PVA solution, stirred at 1000rpm for 20min and then 150mg of CuSO was added₄·5H₂O and 75mg Na₂S₂O₃·5H₂O was added to the PVA solution to give a green colloidal solution.

3) The mixture was then heated to 80 ℃ for 2 h. After the reaction was completed, it was allowed to cool to room temperature. The product was taken out and rinsed three times with deionized water, and then the product was dried in an oven at 50 ℃ for 5h to obtain a CuS-coated stent.

Comparative example 1

A method for preparing a bracket for adsorbing nano copper sulfide on a nickel-titanium alloy wire,

firstly, cleaning the surface of a nickel-titanium alloy stent, then spraying the prepared solution containing copper sulfide nano particles on the surface of the stent, taking out the product, washing the product with deionized water once, and then drying the product in an oven at 50 ℃ for 1h to obtain the stent with the surface adsorbed with CuS.

Referring to fig. 1, fig. 1 is a scanning electron micrograph of a nitinol stent wire grown from untreated nano-copper sulfide particles showing no coating on the stent surface as a comparative example.

Referring to fig. 2, fig. 2 is a scanning electron microscope image of a nickel-titanium stent covered with nano copper sulfide particles, and comparing fig. 1 and fig. 2 shows that the nano copper sulfide particles are effectively coated on the surface of the stent.

Referring to the attached figure 3, figure 3 is an enlarged scanning electron microscope image of the in-situ grown nano copper-nickel-titanium sulfide stent, and it can be seen from the image that nano copper sulfide particles are uniformly distributed and have uniform size.

Referring to fig. 4, fig. 4 is a schematic diagram of the element distribution of the scanning electron microscope of the nickel-titanium stent wire coated with the nano-copper sulfide particles in example 3. The N, Ni and Ti elements show that the stent selected before being coated is a nickel-titanium alloy stent which is approved for clinical use; the effectiveness of the method in the embodiment is verified by Cu and S elements, which shows that the method can grow the copper sulfide nano-particles by in-situ reduction.

Referring to fig. 5, fig. 5 is a scanning electron microscope image of the stent prepared by sputtering copper sulfide nanoparticles in comparative example 1, and it can be seen from the image that the sputtered copper sulfide nanoparticles are extremely uneven, are mostly agglomerated, and easily fall off, which directly affects the subsequent application of the stent.

Referring to the attached drawing 6, fig. 6 is a scanning electron microscope image of the nickel titanium stent wire covered by the nano copper sulfide particles after multiple laser irradiation, and the image shows that the nano copper sulfide particles are stable in property after being coated, and are effectively anchored on the surface of the stent, and the repeated irradiation laser does not damage the stent, so that the stent can achieve the effect of long-term treatment.

Referring to fig. 7, fig. 7 is a temperature change curve measured by placing the stent filaments covered with the copper sulfide nanoparticles in an aqueous solution and irradiating the stent filaments with near-infrared laser for 3 minutes, the conventional nitinol stent has no photothermal conversion function and is harmless to cells, while the stent coated with the copper sulfide nanoparticles has an obvious temperature rise after irradiation, which verifies that the copper sulfide nanoparticle coated stent can be effectively used for photothermal conversion and cancer cell killing.

Referring to fig. 8, fig. 8 is a temperature change curve measured after the nano copper sulfide stent filaments are placed in an aqueous solution and irradiated by near infrared laser for multiple times, and it can be known from the graph that the performance of the nano copper sulfide particle-coated stent is still stable after the nano copper sulfide particle-coated stent is irradiated by the laser for multiple times.

Referring to fig. 9, fig. 9 shows the apoptosis of cancer cells after incubation with copper sulfide nanoparticles for 8h, with and without irradiation of near infrared (1064nm) laser. Red fluorescence in the cells shows that the copper sulfide nanoparticles can effectively promote cancer cell apoptosis after laser irradiation, and further have potential application values of killing tumor cells and ablating tumors.

The above examples are only intended to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A memory alloy esophageal stent modified by a nano copper sulfide coating comprises a stent and is characterized in that a layer of nano copper sulfide particles is uniformly covered on the surface of the stent;

the preparation method of the memory alloy esophageal stent modified by the nano copper sulfide coating comprises the following steps:

reducing dopamine under an alkaline condition to obtain a polydopamine-coated memory alloy stent, and then efficiently adsorbing copper ions by the polydopamine under a heating condition to grow copper sulfide in situ to obtain the memory alloy esophageal stent modified by the nano copper sulfide coating.

2. The memory alloy esophageal stent modified by the nano copper sulfide coating according to claim 1, wherein the stent is a columnar latticed stent woven by nickel-titanium alloy wires.

3. The esophageal stent made of a memory alloy modified by a nano copper sulfide coating according to claim 1, wherein the nano copper sulfide particles have a particle size of 50-150 nm.

4. The memory alloy esophageal stent modified by the nano copper sulfide coating according to claim 1, wherein the preparation method of the memory alloy esophageal stent modified by the nano copper sulfide coating specifically comprises the following steps:

1) preparing a dopamine-coated nickel-titanium stent: cleaning a nickel-titanium alloy stent, immersing the nickel-titanium alloy stent in 1-15 mM Tris-HCl or Tris-buffer solution, adding dopamine into the solution to enable the final solubility of the dopamine to be 1-10 mg/mL, stirring the solution for 8-15 hours in a dark place, taking out the stent, and cleaning the polydopamine coating stent by using deionized water;

2) immersing the polydopamine-coated stent in 400 mL of 0.5-5 mg/mL PVA solution, stirring at 1000rpm for 10-40min, and then adding 100-500mgCuSO₄·5H₂O and 50-150mg Na₂S₂O₃·5H₂Adding O into the PVA solution to obtain a green colloidal solution;

3) and heating the mixed solution to 60-90 ℃ and keeping the temperature for 2 h, naturally cooling to room temperature after the reaction is finished, taking out the product, cleaning and drying to obtain the memory alloy stent covered with the CuS nano-particles.

5. The memory alloy esophageal stent modified by the nano copper sulfide coating according to claim 4, wherein the pH of the Tris-HCl or Tris-buffer solution in the step 1) is 8.5.

6. The esophageal memory alloy stent modified by the nano copper sulfide coating as claimed in claim 4, wherein the product obtained in step 3) is rinsed with deionized water three times after being taken out.

7. The memory alloy esophageal stent modified by the nano copper sulfide coating according to claim 4, wherein the drying temperature in the step 3) is 60 ℃ and the drying time is 3-5 h.