KR20130013206A - Non-vascular drug-eluting stent membrane using electrospinning, and method for preparing the same - Google Patents

Abstract

PURPOSE: A non-vascular drug discharge stent membrane and a method for manufacturing the same are provided to suppress the growth of tumor. CONSTITUTION: A method for manufacturing a non-vascular drug discharge stent membrane comprises a step of preparing a drug coating solution by dissolving polyurethane and an anticancer drug in an organic solvent, a step of forming a first coating layer on a metal stent by covering the metal stent with a silicone tube or the Teflon, and a step of manufacturing a stent membrane by forming a second coating layer on the metal stent. [Reference numerals] (A) Comparative embodiment 1; (B) Embodiment 1

Description

Non-vascular drug-eluting stent membrane using electrospinning, and method for preparing the same}

The present invention relates to a non-vessel drug-releasing stent membrane using electrospinning and a method of manufacturing the same.

In general, stents in the organs consisting of blood vessels, airways, esophagus, biliary tract, etc., narrow the inside of the tubes due to thrombus, malignant and benign tumors, which can cause blood circulation, difficulty breathing, and stagnation of bile. It is used to expand the lumen, which is blocked or narrowed.

In the case of vascular stents, it was developed to expand the lumen of the clogged cardiovascular vessel to facilitate blood supply. However, after a certain period of time after the stent procedure, the stenosis is frequently accumulated due to the accumulation of blood clots and fat in the stent lumen. In order to solve this problem, a drug-releasing stent that coats the stent with a small amount of drug that can inhibit cell differentiation and continuously releases the drug to suppress vascular stenosis has been marketed in early 2000 and has been successfully used in clinical practice. Representative drug release stents include paclitaxel-coated DES (TAXUS ^™ , Express ^™ ) or immunosuppressive sirolimus eluting stent (Cypher ^™ ) (see Korean Journal of Gastroenterology 2007; 49: 294-299). ). The patented technology of drug release stents is classified according to the method of supporting the drug on the stent, 1) a method of directly attaching the drug to the metal stent, 2) a method of loading the drug into the pores of the porous metal stent, and 3) There is a method of binding a drug to a polymer coated on the stent, and various technologies are still being developed.

Non-vascular stents are used to broaden the digestive tract (biliary duct, large intestine, etc.) or bronchial lumen or to prevent the progression of stenosis by malignant tumors such as cancer or by overgrown tissues (benign tumors). However, even for non-vascular stents, when the stent is maintained for a long time, tissue is squeezed out between the stents and restenosis occurs. The restenosis rate is almost 50% or more, and in order to solve the problem, a method of strengthening the stent's elasticity through a new stent design has been attempted, but it has not been very successful (Korea Patent Publication No. 10-0497512, Republic of Korea Patent Registration) 10-0548781). Alternatively, a sleeve-like stent was attempted to surround the stent with a cylindrical coating to prevent tissue from bleeding out.

Recently, a study is being conducted on drug-released non-vascular stents that can inhibit the growth of cancerous tissues by allowing non-vascular stents to carry anticancer drugs and elute them over time like vascular stents (Korea Patent Publication No. 10- 0888219, Republic of Korea Patent Publication No. 10-0883329). However, vascular stent technology used in coronary artery disease, etc. and technology for supporting a drug in a non-vascular stent can be said to be a different technology area. First, the amount of drug to be supported is low concentrations of several tens of micrograms in the non-blood system, but in the case of the vascular system should be loaded with an anticancer agent of about mg to obtain an anticancer effect. In addition, a carrier capable of supporting a drug is supported by a polymer coating on the surface of the stent having a diameter of 1 to 2 mm in the case of a vascular stent, and in the case of a non-vascular stent, the carrier is not able to support the drug on the surface of the stent. The drug is supported on the polymer film and the size of the stent is 1cm inside diameter and 4-15cm long, which is different from the vessel stent.

According to the existing technology, the drug-releasing non-vascular stent is obtained by dipping a 1 cm diameter Teflon rod into a coating solution in which drugs and polymers are dissolved, and then taken out and dried to form a round cylindrical drug bearing film, which is then cut to an appropriate length. It will be created by covering the stent. When the drug-supported film is manufactured by the dipping method, 1) the surface of the membrane is rough and the thickness is not constant, 2) the distribution of the supported drug is not uniform, and 3) the initial release amount of the drug is too large or not released. There are a number of problems, including poor and persistent release control.

Electrospinning, on the other hand, was the scientific basis for Raleigh's calculation that electrostatic forces could overcome surface tensions when a liquid dropped in 1882, and was patented by German engineer Formhals in 1934. It is a method to obtain a product by spun instantaneously in the form of fibers using a polymer of a low viscosity state. Electrospinning has been used to make nanofibers with a diameter of 20nm to 1㎛ for about 10 years, and is a new technology that is in the spotlight. Nanofibers have a very fine diameter and therefore have a significantly larger surface area than conventional fibers. Therefore, when using it for the filter it can maximize the efficacy.

As described above, the nanofibers produced by electrospinning have a surface area of several hundred times that of the existing fibers and their porosity is very good. Thus, when manufacturing a polymer film in which the drug is carried by electrospinning, there is a problem due to dipping. It is thought that stable dissolution behavior of supported and resolved drugs can be expected.

The present inventors studied the stent membrane exhibiting stable dissolution behavior of the drug, and prepared a stent membrane by electrospinning a drug coating solution in which a polyurethane and an anticancer agent dissolved in an organic solvent to a metal stent, and the surface of the prepared stent membrane The homogeneous, uniform thickness and stable drug release control showed a continuous drug release effect, significantly inhibit the growth of the tumor, significantly reduced the weight of the tumor, and completed the present invention.

Accordingly, the present invention is to provide a non-vessel drug release stent membrane using electrospinning and a method of manufacturing the same.

The present invention

1) preparing a drug coating solution by dissolving a polyurethane and an anticancer agent in an organic solvent, and

2) inserting a metal stent into a teflon rod, mounting it on a roller, and rotating it to electrospin the drug coating solution prepared in step 1) to prepare a stent membrane, the non-vascular drug using electrospinning Provided are methods of making the release stent membrane.

In addition,

1) preparing a drug coating solution by dissolving a polyurethane and an anticancer agent in an organic solvent,

2) inserting a metal stent on a teflon rod and covering the silicon tube or teflon thereon to form a primary coating layer on the metal stent,

3) preparing a stent membrane by electrospinning the drug coating solution prepared in step 1) by mounting a teflon rod into which a metal stent on which the primary coating layer is formed is inserted and rotating the roller, and then forming a second coating layer on the metal stent. It provides a method for producing a drug-releasing stent membrane for non-vascular using electrospinning comprising the step.

The present invention also provides a non-vascular drug release stent membrane prepared by the above method.

Hereinafter, the present invention will be described in detail.

The non-vessel drug-releasing stent membrane according to the present invention is prepared by electrospinning a drug coating solution in which a polyurethane and an anticancer agent are dissolved in an organic solvent while putting a metal stent on a teflon rod, and then mounting and rotating it on a roller. .

In addition, the non-vessel drug-release stent membrane according to the present invention, by inserting a metal stent on the Teflon rod and covered with a silicon tube or Teflon thereon to form a primary coating layer on the metal stent and then mounted on a roller and rotated, It is characterized in that it is prepared by electrospinning a drug coating solution in which a polyurethane and an anticancer agent are dissolved in a solvent to form a secondary coating layer on a metal stent.

Hereinafter, a method for preparing a non-vascular drug release stent membrane according to the present invention will be described in detail.

First, a polyurethane and an anticancer agent are dissolved in an organic solvent to prepare a drug coating solution. The organic solvent includes tetrahydrofuran (THF), acetone, methanol, dimethylacetamide (DMAc), methylene chloride, ethyl acetate, toluene, dimethylformamide (DMF), chloroform and mixed solvents thereof, It is not limited to this.

The content of the polyurethane is 5 to 25% by weight, preferably 10 to 20% by weight based on the total weight of the mixed solvent.

The anticancer agents include doxorubicin, paclitaxel, docetaxel, gemcitabine, navelbine, capecitabine, cyclophosphamide, 5-fluorouracil, methotrexate, epirubicin, cisplatin, herceptin, and the like. Including, but not limited to. The content of the anticancer agent is preferably 0.1 to 10.0% by weight, preferably 1.0 to 5.0% by weight based on the total weight of the mixed solvent.

The drug coating solution may be prepared by adding an additive such as a drug release controlling agent or preservative. The drug release controlling agent is preferably polyethylene glycol, but is not limited thereto. The amount of the additive is preferably 1 to 5% by weight based on the total weight of the mixed solvent.

Then, the stent membrane is prepared by placing a metal stent on a Teflon rod, then mounting the roller and rotating the drug coating solution while rotating.

Alternatively, by inserting a metal stent on a teflon rod and covering it with a silicon tube or teflon to form a primary coating layer on the metal stent, and then mounting and rotating it on a roller, the drug coating solution is electrospun and the secondary coating layer on the metal stent. To form a stent membrane. The stent membrane on which the secondary coating layer is formed may be dried and then electrospun with a drug coating solution to form a third coating layer.

Forming the primary coating layer on the metal stent as described above, can greatly improve the warning and corrosion resistance of the stent coating, prevent the drug release to the gastrointestinal lumen and release the drug only to the cancer tissue directionality of drug release Can give

In the metal stent, the metal includes one or more selected from the group consisting of nickel, titanium, stainless steel, cobalt, chromium, tantalum (Ta), gold, platinum, silver, magnesium, and alloys thereof, but is not limited thereto. .

As the electrospinning conditions, the distance from the nozzle to the stent is 10 to 15 cm, the stent rotation speed is 300 to 500 rpm, the applied voltage is 0.7 to 1.5 kV, and the total spinning time is 1 to 8 hours, preferably 2 to 4 hours. The flow rate is 0.3-1 ml / hr, preferably 0.5 ml / hr.

Non-vascular drug release stent membrane prepared by the above method, the surface is homogeneous and the thickness is constant compared to the stent membrane prepared by the dipping method, the drug is constantly released in a constant amount is well controlled dissolution. In addition, the non-vascular drug release stent membrane of the present invention significantly inhibits tumor growth, significantly reduces the weight of the tumor, and has a continuous drug release effect through stable drug release control, so that drugs exist in cancer tissues over time. .

Accordingly, the non-vascular drug-releasing stent membrane according to the present invention can be usefully used to widen the narrowed lumen or prevent the progression of the narrowing caused by the development of a tumor such as cancer.

The non-vessel drug release stent membrane using the electrospinning according to the present invention exhibits a continuous drug release effect by controlling the uniform drug release, stable thickness, and stable drug release compared to the stent membrane manufactured by the dipping method, and showing tumor growth. Significantly inhibit and significantly reduce the weight of the tumor.

Figure 1 is a schematic diagram showing the manufacturing process of the non-vessel drug release stent membrane using the electrospinning of the present invention.
2 is a diagram showing the results of visually confirming the non-vessel drug-releasing stent membrane according to the present invention (A) and the result of observing it with a scanning electron microscope (SEM) (B).
Figure 3 is a visual observation of the homogeneity of the non-vessel drug release stent membrane according to the present invention ((A) stent membrane prepared by the dipping method, (B) stent membrane prepared using electrospinning).
Figure 4 is a view showing the drug dissolution behavior of the non-vessel drug release stent membrane according to the present invention ((A) stent membrane prepared by the dipping method, (B) stent membrane prepared using electrospinning).
Figure 5 is a diagram showing the results of X-ray diffraction analysis of the non-vessel drug release stent membrane according to the present invention.
6 is a diagram showing the tumor size (A) and weight (B) after inserting the non-vascular drug-releasing stent membrane according to the present invention into BALB / C mice causing colorectal cancer.
7 is a diagram showing the residual amount of paclitaxel in the tissue after inserting the non-vascular drug-releasing stent membrane according to the present invention into BALB / C mice causing colorectal cancer [(A) Paclitaxel injection (PTX) group, ( B) group of paclitaxel containing electrospun stent membranes (PTX-ESM).

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided only for the purpose of easier understanding of the present invention, and the present invention is not limited by the examples.

Example  One  : Electrospinning For non-vascular use  Drug release Stent Membrane  Produce

Dimethylacetamide (DMAc) and tetrahydrofuran (THF) were mixed in a weight ratio of 7: 3, followed by dissolving 12 to 15% by weight of polyurethane. Next, 1.5-3.0 wt% of paclitaxel was added to prepare a drug coating solution.

Then, a nickel-titanium stent was put on the Teflon rod, mounted on a roller, and rotated at 300 to 500 rpm, and the drug coating solution was electrospun at a flow rate of 0.5 ml / hr for 2 to 4 hours at an applied voltage of 0.7 to 1.5 kV. To prepare a stent membrane. At this time, the distance from the nozzle to the stent was 10 to 15 cm.

The manufacturing process of the non-vessel drug release stent membrane using the electrospinning of the present invention is schematically shown in Figure 1, the result of visually confirming the prepared non-vessel drug release stent membrane (A) and enlarged the scanning electron The result (B) observed under a microscope (SEM) is shown in FIG. 2.

Example  2  : Electrospinning For non-vascular use  Drug release Stent Membrane  Produce

Dimethylacetamide (DMAc) and tetrahydrofuran (THF) were mixed in a weight ratio of 7: 3, followed by dissolving 12 to 15% by weight of polyurethane. Next, 2.5 wt% gemcitabine and 2.5 wt% docetaxel were added to prepare a drug coating solution.

After dipping the teflon rods into the silicone solution and drying at 120 ° C. for at least 5 hours, the dried silicon tube was removed from the teflon rods. Then, insert the nickel-titanium stent into the Teflon rod, put the silicon tube on it again, and then mount it on a roller and rotate it at 300 to 500 rpm while 0.5 ml of the drug coating solution was applied for 2 to 4 hours at an applied voltage of 0.7 to 1.5 kV. The membrane was prepared by electrospinning at a flow rate of / hr. At this time, the distance from the nozzle to the stent was 10 to 15 cm.

Example  3  : Electrospinning For non-vascular use  Drug release Stent Membrane  Produce

A nickel-titanium stent was inserted into the Teflon rod and Teflon was put thereon to form a primary coating layer. Teflon rods with the stent with the first coating layer formed thereon were mounted on a roller and rotated at 300 to 500 rpm, and electrospun under the same conditions as in Example 2 with the drug coating solution prepared in Example 2 to form a second coating layer. Membranes were prepared. After drying the teflon rod into which the stent on which the secondary coating layer was formed was dried at room temperature, and again by electrospinning with the drug coating solution prepared in Example 2 under the same conditions as in Example 2, a third coating layer was formed to prepare a stent membrane. Can be.

Example  4  : Electrospinning For non-vascular use  Drug release Stent Membrane  Produce

Dimethylacetamide (DMAc) and tetrahydrofuran (THF) were mixed in a weight ratio of 7: 3, followed by dissolving 12-15 wt% of polyurethane and 2 wt% of polyethylene glycol, a release controlling agent. Next, 1.5-3.0 wt% of paclitaxel was added to prepare a drug coating solution. A stent membrane was prepared by electrospinning under the same conditions as in Example 1 except that the drug coating solution containing the release control agent prepared above was used instead of the drug coating solution used in Example 1.

Comparative example  One  : Dipping  Used For non-vascular use  Drug release Stent Membrane  Produce

Teflon rods were dipped into the silicone solution and taken out and dried at 120 ° C. for at least 5 hours. Once the silicone was completely dry, the dried silicone tube was removed from the teflon rods. Then, thinly wrapped the aluminum foil on the Teflon rod, covered with nickel-titanium stent, silicon tube in order, immersed in the drug coating solution prepared in Example 2 at a rate of 1 cm / s and taken out at 50 ℃ for at least 24 hours Drying made a stent membrane.

Comparative example  2  : Contains no drugs using electrospinning Stent Membrane  Produce

In Example 1, the stent membrane was prepared in the same manner as in Example 1, except that paclitaxel was not included in the polyurethane coating solution preparation. The drug-free stent membrane prepared above was used to compare efficacy with the drug-containing stent membrane in animal cancer models.

Experimental Example  One  : Stent Membrane  Check homogeneity

In order to confirm the homogeneity of the stent membrane of the present invention, the following experiment was performed. Specifically, blue ink was added to the drug coating solution used in the preparation of the stent membrane in Example 1 and Comparative Example 1, and red ink was added to the silicon solution to prepare a stent membrane. The homogeneity of each stent membrane was then visually observed.

The results are shown in FIG.

As shown in Figure 3, in the case of the stent membrane (Comparative Example 1) prepared by the dipping method was confirmed that the surface is uneven and the thickness is different for each part. On the other hand, in the case of the stent membrane (Example 1) prepared using the electrospinning it was confirmed that the surface is uniform and the thickness is constant.

Experimental Example  2  : Stent Membrane  Drug dissolution experiment

In order to confirm the drug dissolution behavior of the stent membrane of the present invention, the following experiment was performed.

The stent membranes prepared in Example 1 and Comparative Example 1 were each placed in a 50 ml conical tube, and 50 ml of 0.01 M phosphate buffer was added thereto. Then, the drug dissolution experiment was carried out for 30 days in a shaker at 37 ℃, 50rpm.

The results are shown in Fig.

As shown in FIG. 4, in the case of the stent membrane (Comparative Example 1) prepared by the dipping method, the drug was initially released and was not released thereafter, so that the dissolution was not well controlled. However, in the case of the stent membrane prepared using electrospinning (Example 1), the drug was released in a constant amount for 30 days, it was confirmed that the elution is well controlled.

Experimental Example  3  : Stent Membrane  X-ray diffraction  analysis

For X-ray diffraction analysis of the stent membrane of the present invention, it was performed using an X-ray diffractometer (PANalytical's X'Pert PRO). Specifically, the paclitaxel powder (PTX), the electrospinning stent membrane (ESM) containing no paclitaxel prepared in Comparative Example 2, and the electrospinning stent membrane containing the paclitaxel prepared in Example 1 (PTX-ESM ) Was analyzed in the 5 ~ 40 ° intervals. At this time, the angular resolution was 0.02 degrees.

The results are shown in Fig.

As shown in Figure 5, it was confirmed that the specific peak of paclitaxel disappeared in the electrospun stent membrane (PTX-ESM) containing the paclitaxel of the present invention. This is believed to have disappeared certain peaks due to the interaction between the polyurethane and paclitaxel.

Experimental Example  4  : Measurement of tumor size and weight

CT-26 metastatic mouse colon cancer cells were cultured in DMEM (dulbecco's modified eagle medium) medium supplemented with 10% fetal bovine serum (FBS). Cells that reached 60-70% confluency were washed with Han's balanced salt solution (HBSS), separated with trypsin / EDTA, and trypsin neutralizing solution was added. For injection, cells were resuspended in complete medium. As experimental animals, 20 BALB / C mice were purchased from Orient Co., Ltd., and divided into four groups by assigning five animals per group [① control group, ② drug-free electrostent stent membrane group (ESM), ③ paclitaxel injection group (PTX-inj), ④ drug-containing electrospun stent membrane group (PTX-ESM)].

The cultured cells (1.0 × 10 ⁶ ) were injected subcutaneously in BALB / C mice of each group. One week after the injection, when the average diameter of the tumor was about 6 mm and the size of the tumor was about 0.5 × 0.5 × 0.5 cm, the tumor- and subcutaneous layers of the mice in each group did not contain drug-free electrospinning. The stent membrane (Comparative Example 2), paclitaxel injection, drug containing electrospun stent membrane (Example 1) were treated. Tumor size and weight were measured for 22 days.

Tumor size (A) and weight (B) are shown in FIG. 6.

As shown in Figure 6, in the drug-containing electrospun stent membrane group (PTX-ESM) of the present invention it was confirmed that the growth of the tumor was significantly inhibited, the weight of the tumor was significantly reduced.

Experimental Example  5  : Cancer tissue  of mine Paclitaxel  Residual amount

In order to confirm the residual amount of paclitaxel in the cancer tissue, experiments were performed in the paclitaxel injection (PTX) group and the paclitaxel-containing electrospun stent membrane (PTX-ESM) group. Specifically, the BALB / C mice causing colorectal cancer were treated with paclitaxel injection and the paclitaxel-containing electrospun stent membrane prepared in Example 1, and the tissues of the mice were treated on the 1st, 7th, 14th and 21st days. Blood was collected. Cancer tissue was diluted with distilled water and homogenized. Then, the residual amount of paclitaxel remaining in the cancer tissue and blood of the mouse was measured.

The results are shown in Fig.

As shown in FIG. 7, in the case of paclitaxel injection, a very large amount of paclitaxel was detected in tissues one day after the injection, but almost no paclitaxel was found in the tissues after one week. On the other hand, in the case of the paclitaxel-containing electrospun stent membrane (PTX-ESM), the drug was slowly released from the stent, and the initial detection amount of paclitaxel was 1/3 or less of the paclitaxel injection, and it was confirmed that paclitaxel was present in the tumor even after 21 days. That is, paclitaxel-containing electrospun stent membrane (PTX-ESM) has a stable drug release effect for more than 30 days due to stable release control and low toxicity is more safe.

Claims (12)

1) preparing a drug coating solution by dissolving a polyurethane and an anticancer agent in an organic solvent, and
2) inserting a metal stent into a teflon rod, mounting it on a roller, and rotating it to electrospin the drug coating solution prepared in step 1) to prepare a stent membrane, the non-vascular drug using electrospinning Method for preparing the release stent membrane. 1) preparing a drug coating solution by dissolving a polyurethane and an anticancer agent in an organic solvent,
2) inserting a metal stent on a teflon rod and covering the silicon tube or teflon thereon to form a primary coating layer on the metal stent,
3) preparing a stent membrane by electrospinning the drug coating solution prepared in step 1) by mounting a teflon rod into which a metal stent on which the primary coating layer is formed is inserted and rotating the roller, and then forming a second coating layer on the metal stent. Comprising a step, a method for producing a non-vessel drug release stent membrane using electrospinning. The organic solvent of claim 1 or 2, wherein the organic solvent is tetrahydrofuran (THF), acetone, methanol, dimethylacetamide (DMAc), methylene chloride, ethyl acetate, toluene, dimethylformamide (DMF) and chloroform. Method for producing a non-vessel drug release stent membrane using electrospinning, characterized in that at least one selected from the group consisting of. According to claim 1 or 2, wherein the content of the polyurethane is characterized in that 5 to 25% by weight based on the total weight of the mixed solvent, the method for producing a non-vessel drug release stent membrane using electrospinning. The method of claim 1 or 2, wherein the anticancer agent is doxorubicin, paclitaxel, docetaxel, gemcitabine, navelbine, capecitabine, cyclophosphamide, 5-fluorouracil, methotrexate, epirubicin Method for producing a non-vessel drug-releasing stent membrane using electrospinning, characterized in that at least one selected from the group consisting of shin, cisplatin and herceptin. According to claim 1 or 2, wherein the content of the anticancer agent is characterized in that 0.1 to 10.0% by weight based on the total weight of the mixed solvent, the method for producing a non-vessel drug release stent membrane using electrospinning. The method of claim 1 or 2, wherein the drug coating solution preparation further comprises a drug release control agent or preservative, characterized in that the method for producing a non-vessel drug release stent membrane using electrospinning. 8. The method of claim 7, wherein the drug release modulator is polyethylene glycol. The metal stent of claim 1, wherein the metal is 1 selected from the group consisting of nickel, titanium, stainless steel, cobalt, chromium, tantalum (Ta), gold, platinum, silver, magnesium, and alloys thereof. A method for producing a non-vessel drug-releasing stent membrane using electrospinning, characterized in that more than one species. The method of claim 1 or 2, wherein the electrospinning conditions include a distance from the nozzle to the stent of 10 to 15 cm, a stent rotation speed of 300 to 500 rpm, an applied voltage of 0.7 to 1.5 kV, and a total spinning time of 1 to 8 Method for producing a non-vessel drug-releasing stent membrane using electrospinning, characterized in that the time, flow rate is 0.3 ~ 1ml / hr. The method according to claim 2, further comprising, after step 3), drying the stent membrane on which the secondary coating layer is formed and electrospinning with the drug coating solution to form a third coating layer. Method for producing a drug-releasing stent membrane for non-vascular. A non-vascular drug release stent membrane prepared by the method of claim 1.

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