A kind of medicinal balloon and preparation method thereof
Technical field
The invention belongs to medical instruments field, be specifically related to a kind of medicinal balloon and preparation method thereof.
Background technology
Angiostenosis is morbidity and main causes of death, and therapeutic modality the most frequently used at present adopts bracket for eluting medicament (DES) interventional therapy.DES is coated on rack surface after being mixed with polymeric matrix by medicine, forms topical remedy's slow releasing system.When after stenter to implant blood vessel, medicine meeting slow release continued for several weeks, to time several months, adds the supporting role of upper bracket, effectively can treat the narrow or inaccessible of blood vessel, is one of the most conventional at present and the most effective intervention apparatus.But DES also has many weak points, such as, polymer can produce local chronic inflammatory reaction; The existence of support needs Long-term Anti antiplatelet drug treatment; Medication coat skewness; After Thrombosis in sten, should not implant frame etc. again.
In order to overcome above-mentioned deficiency, especially seek to solve in-stent restenosis, lower Extremity Arterial Diseases, vascular bifurcation place and thin vessels the problem such as narrow time a kind of novel product--the medicament elution sacculus (DEB) that has been born.DEB technology is a kind of balloon reconstruction of improvement, sacculus, at sacculus outer surface medication, is delivered to lesion locations by conduit by this technology, and (0-2min) discharges medicine within the blink of balloon expandable, play blood vessel dilating, treat narrow or inaccessible effect.Even if lesion vessels generation restenosis blocks, also carry out Retreatment by DEB.
But current medicinal balloon requires that the medicine being used for the treatment of disease must have such effect: namely reached the object of curing the disease by single-bolus high-dose administration, repeat administration is nonessential.This greatly limits the selection of medicine, and after disposable heavy dose of administration, medicine enters blood circulation and easily causes acute toxic reaction.
Current biodegradable stent part overcomes the limiting factor of traditional DES, and the reaction that can not cause inflammation, with endothelialization is difficult again, can discharge medicine lentamente relative to DEB.But because its release limited area, and the factors such as the support strength of support is undesirable, easy fracture, can not produce a desired effect.So, be necessary the feature of the feature that comprehensive medicinal balloon Chinese medicine evenly discharges and the medium-term and long-term slow releasing of drug stent, thus develop a kind of newly containing medicine coating.
WO2012/039884A1 discloses a kind of transferable polymer coating, by water-soluble material and degradable polymer are coated in common balloon surface respectively, then whole coating is immersed a period of time in aqueous solution, dissolve the water-soluble material of nexine, thus form the structure of a nested biodegradable polymer layer outside sacculus.The shortcoming of this invention is: (1) nexine water-soluble material is tightly wrapped quilt by outer degradable polymer, and hydrone is difficult to cross outer barrier, even if soak for a long time in a lot of situation, internal layer water-soluble material can not dissolve; On the other hand, even if the water-soluble material of nexine dissolves, its aqueous solution is also difficult to flow out, although this kind of solution has certain lubricity under having water existent condition, once after coating drying, again by sacculus and outer adhesion with hydrone completely; (2) even if by immersion treatment, nexine is completely removed, and does not have entity to be connected between balloon wall with biodegradable polymer layer, and in processing procedure that this directly causes that the folding pressure in drug coat and later stage is held etc., the movement of polymeric layer, even comes off; (3) in addition, polymeric layer is a very thin skim, do not have the supporting role as support, also can not be initiatively adherent, once after sacculus withdraws from, the thin film residing in blood vessel place is easy to be washed away by blood flow, does not only have the object of disease therapy, even causes serious blood vessel embolism.
Chinese invention patent application No.200610025200.8 discloses a kind of double-layered balloon catheter, in two-layer sacculus, internal layer sacculus plays the effect of blood vessel dilating, and outer sacculus is made up of the microporous membrane of uniqueness, the gene of therapeutical effect or medicine can will be played by outer sacculus osmosis on blood vessel wall, target organ.This invention effectively overcomes the loss of medicine in angiography catheter in course of conveying, reduces system toxicity, but does not reach the object of long-acting slow-release.
Summary of the invention
In order to solve an above difficult problem, the present invention devises a kind of coating of medicinal balloon, and this coating coordinates special double-layered balloon.During operation, first internal layer sacculus carries out angioplasty, then outer balloon expandable.In the process, the solution such as normal saline ooze out from the aperture of outer balloon wall, dissolved water dissolubility bottom, thus make the effect of bottom become lubricating layer from articulamentum, the biodegradable polymer layer (thin film) of drug containing departs from from the surface of outer sacculus, then is withdrawn from by sacculus external.The biodegradable polymer layer of drug containing evenly discharged medicine at whole diseased region within the several minutes time to the several months.Biodegradable polymer layer (thin film) also can comprise adhesive, makes it stick to blood vessel and has certain toughness, can not rupture, also can not come off from diseased region because of external force such as the compressing of blood vessel, torsions as support.
Specifically, the invention provides a kind of medicinal balloon, comprise double-layered balloon, it is characterized in that, the outer balloon surface of described double-layered balloon is provided with coating, described coating comprises the biodegradable polymer layer of water solublity bottom and drug containing successively.
According to the present invention, described medicine is scattered in biodegradable polymer layer, or is separately coated with one deck medicine layer on biodegradable polymer layer.
According to the present invention, the biodegradable polymer layer of described drug containing is further containing adhesive.In this case, described biodegradable polymer layer is the Rotating fields comprising biodegradable polymer, adhesive and medicine, or comprises the double-decker of three's combination in any, or is the three-decker be coated with respectively.
According to the present invention, a described Rotating fields is by after biodegradable polymer, adhesive and medicine blending, is coated on together on water solublity bottom.
According to the present invention, described double-decker can combination in any, as long as after combination, comprise biodegradable polymer, adhesive and medicine just.Such as, described double-decker can be that degradable polymer and adhesive form a Rotating fields, and medicine forms separately another Rotating fields, or degradable polymer forms separately a Rotating fields, and adhesive and medicine form another Rotating fields, or degradable polymer and adhesive form a Rotating fields, and medicine and adhesive form another Rotating fields, or degradable polymer and medicine form a Rotating fields, and adhesive forms separately a Rotating fields, or degradable polymer, adhesive and medicine form a Rotating fields, and adhesive and/or medicine and/or degradable polymer form another Rotating fields etc.
According to the present invention, described three-decker can arrange in random order, such as, is biodegradable polymer structure sheaf, adhesive structure sheaf and medicines structure layer successively.
Those skilled in the art can understand, no matter be double-decker or three-decker, in order to ensure that bilayer or three-decker adhere to blood vessel, containing the structure sheaf of adhesive be exposed in whole or in part outside, to dissolve at water solublity bottom, can contact with blood vessel after release.
The present invention also provides a kind of preparation method of medicinal balloon, comprises and provides double-layered balloon, makes water solublity bottom, then make the biodegradable polymer layer of drug containing and optional adhesive in its outer balloon surface.
Described biodegradable polymer layer can be attached to the blood vessel of lesion region, within the time do not waited to the several months for several minutes, discharge medicine.
Disclosed in described double-layered balloon and Chinese invention patent application No.200610025200.8, sacculus is completely the same.
Described water solublity bottom, also known as hydrophilic bottom layer, has certain adhesion strength under anhydrous state, for connecting the biodegradable polymer layer of balloon surface and drug containing and optional adhesive; Can dissolve rapidly once meet water, form lubricating layer, thus smoothly biodegradable polymer layer is discharged.Described water-soluble material comprises the water-soluble macromolecules such as starch based, cellulose, plant gum, animal glue; Modified starch and modified cellulose; The chemically modified natural polymerses such as carboxymethyl starch, acetic starch, hydroxy methocel, carboxymethyl cellulose; The synthetic polymers such as polyacrylamide (PAM), hydrolyzed polyacrylamide (HPAM), polyvinylpyrrolidone (PVP).
The biodegradable polymer layer of described drug containing and optional adhesive is capable of being fast degraded or dissolve, and such as several days after surgery even less, such as postoperative 5 minutes to 24 hours again.In yet some other cases, described biodegradable polymer layer can slowly be degraded or dissolve, such as from 5 days to 6 months not etc.In this process, biodegradable polymer layer combination medicine is attached to lesion vessels inwall until medicine is completely absorbed or coating is degradable.The thickness of biodegradable polymer layer can make the appropriate adjustments according to required degradation time, is generally less than 10 μm, such as, and 0.2 μm-9 μm or 0.5 μm-8.5 μm.
Described biodegradable polymer can be polyhydroxyalkanoate (PHA), poly butyric ester type compound, poly-poly-alpha-hydroxy acid compounds, polyglycolic acid (PGA), Poly(D,L-lactide-co-glycolide (PLGA), PPDO, polylactic acid-polyethylene oxide copolymer, the hyaluronic acid etc. such as (glycerol-decanedioic acid), polypeptide, polylactic acid (PLA).
Polymeric layer can be adhered to blood vessel tissue place by described adhesive, prevent from coming off, comprise gelatin, starch, agar, mannan, alginic acid, polyacrylic acid, polyacrylate adhesive, dextrin, methylcellulose, methyl vinyl ether, the copolymer of maleic anhydride, arabic gum, tragcanth, karaya, tracasol, cyanoacrylate adhesive, polyurethane tackifier, organosilicon series adhesive, fibrin adhesive, sea-mussel mucin adhesive etc.
Described medicine is antithrombotic, propagation, antiinflammatory, antiinflammatory, anti-proliferate, antitumor, resisting mitosis, T suppression cell, have cell toxicant, angiogenesis inhibitor, anti-restenosis, suppression microtubule, metastasis or antithrombotic material, be preferably acemetacin, aescine, aminopterin, antimycoin, arsenic trioxide, Aristolochic Acid, aspirin, little ?alkali, ginkgol, rapamycin and derivant thereof, paclitaxel, Docetaxel, antibiotic (particularly actinomycin D), hormone, antibody curing cancer drug.
The invention solves the drug absorption time existed in conventional medicament sacculus short, absorbtivity is low, the problem that individual variation is large.After intervene operation, polymeric layer carried drug adhesion and evenly discharge medicine within the time that diseased region did not wait from 5 minutes-6 months.
Medicinal balloon of the present invention has following beneficial effect: (1) its coating coordinates special double-layered balloon, in the process of outer balloon expandable, have the solution such as normal saline ooze out from balloon wall, dissolved water dissolubility bottom makes it change lubricating function into by linkage function, thus controls the release of the biodegradable polymer layer of drug containing; (2) polymeric layer evenly can discharge medicine to whole pathological tissues for a long time, maintains drug level enough around sick cell within considerable time; (3) biodegradable polymer layer (thin film) also can contain adhesive, thus is more conducive to stick to blood vessel and has certain toughness, can not rupture because of external force such as the compressing of blood vessel, torsions as support; (4) without support long-term existence in human body, coating can be degraded or dissolve within the relatively short time, does not affect endothelialization again; (5) relative to traditional medicament elution balloons technique, the present invention reduces drug loss amount, and increase drug absorption, required drug loading is little, little to system toxicity.
Accompanying drawing explanation
In order to more clearly describe technical scheme of the present invention, briefly introduce below in conjunction with accompanying drawing.Obviously, these accompanying drawings are only some detailed description of the invention that the application records.The present invention includes but be not limited to these accompanying drawings.
A kind of medicinal balloon that Fig. 1 provides for the embodiment of the present invention, the Structure of cross section schematic diagram after its internal layer balloon expandable.As shown in the figure, internal layer sacculus can play the effect of angioplasty, and now biodegradable polymer layer is still incorporated into sacculus outer wall securely.
A kind of medicinal balloon that Fig. 2 provides for the embodiment of the present invention, its ectonexine sacculus all expand after Structure of cross section schematic diagram.As shown in the figure, when outer balloon expandable, it expands liquid (as normal saline) and can pass through the aperture of sacculus outer wall thus dissolved by water solublity bottom, thus drug containing is separated with sacculus with the biodegradable polymer layer of optional adhesive.
A kind of medicinal balloon longitudinal section structural representation that Fig. 3 provides for the embodiment of the present invention.
A kind of medicinal balloon that Fig. 4 provides for the embodiment of the present invention withdraws from the structural representation in process at sacculus.As shown in the figure, sacculus is withdrawn from body, and the biodegradable polymer layer of drug containing and optional adhesive adheres to blood vessel, several minutes to the several months not wait dissolving or degradation time in adjacent tissue release medicine.
Detailed description of the invention
In order to understand the present invention further, below in conjunction with embodiment, preferred version of the present invention is described.These describe the feature and advantage just illustrating medicinal balloon of the present invention, but not limit the scope of the invention.
Embodiment 1
1. double-layered balloon preparation
A double-layered balloon is prepared according to the described method of Chinese invention patent application No.200610025200.8.
2. coating preparation
Take 2g polyvinylpyrrolidone (PVP, molecular weight 10,000), join in 5ml isopropyl alcohol (IPA) solution, fully stir until PVP dissolves completely.Expanded by double-layered balloon internal layer, immerse in above-mentioned solution, then dry in 40 DEG C of baking ovens, form water solublity bottom, it is 30.109mm. that calliper records sacculus middle part external diameter
Take 2g Poly(D,L-lactide-co-glycolide (PLGA) (50/50), 0.01g cyanoacrylate and 300mg paclitaxel are dissolved in 10ml oxolane (THF) solution, fully stir until all the components dissolves completely.Then the sacculus scribbling water solublity bottom is immersed in above-mentioned solution, dry in 40 DEG C of baking ovens, repeat immersion 3 times.After drying, recording sacculus middle part external diameter at calliper is 30.121mm.
Known by calculating, the thickness of biodegradable polymer layer is 6 μm.
Embodiment 2
1. double-layered balloon preparation
Method according to Chinese invention patent application No.200610025200.8, prepares a double-layered balloon.
2. coating preparation
Take 2g PVP (molecular weight 10,000), join in 5ml IPA solution, fully stir until PVP dissolves completely.Expanded by double-layered balloon internal layer, immerse in above-mentioned solution, then dry in 40 DEG C of baking ovens, form water solublity bottom, it is 30.109mm that calliper records sacculus middle part external diameter.
Take 2g PLGA (50/50), 0.01g cyanoacrylate is dissolved in 10mlTHF solution, fully stirs until all the components dissolves completely.The sacculus scribbling water solublity bottom is continued to immerse in above-mentioned solution, then dry in 40 DEG C of baking ovens, repeat immersion 2 times, bone dry.Finally, adopting ultrasonic spraying technology to spray one deck paclitaxel at polymer layer surface, for guaranteeing effective bonding of polymer coating and blood vessel, not spraying medicine in the length of each reserved 1mm in these coating two ends.It is 30.126mm that calliper records sacculus middle part external diameter.
Known by calculating, the thickness comprising the biodegradable polymer layer of medicine layer adds up to 8.5 μm.
Embodiment 3
Get the isolated pig arterial blood pipeline section close with balloon diameter, immerse immediately in the Sanguis sus domestica adding anticoagulant, keep 37 DEG C of constant temperature, medicinal balloon keeps 1 minute by 6F conduit in a folded configuration, then sacculus intravasation inner chamber, first internal layer sacculus expands the object that (12atm) reaches angioplastic, then outer sacculus saline injection, after water solublity bottom dissolves and disappears, (about 1 minute) withdraws from sacculus, and biodegradable polymer layer forms thin film and sticks to blood vessel place.
Separately get the latex flexible pipe close with balloon diameter, immerse 37 DEG C of constant temperature phosphate buffer (PBS, pH=7.4) in, medicinal balloon enters latex flexible pipe inner chamber in a folded configuration, first internal layer sacculus is expanded (12atm), then outer sacculus saline injection, after water solublity bottom dissolves and disappears, (about 1 minute) withdraws from sacculus, biodegradable polymer layer forms thin film and sticks to latex tubing inner chamber, what this latex tubing and degradable films are placed in medicament dissolution instrument turns basket, dissolution medium is the constant temperature PBS (pH=7.4) of 37 DEG C ± 0.5 DEG C, rotating speed is 100 revs/min, after sampling process in 1 hour, HPLC testing drug stripping situation.As a result, biodegradable polymer layer was at first 24 hours release about 40% medicines.
The explanation of above embodiment just understands core concept of the present invention for helping.Should be understood that; for the ordinary skill in the art; under the premise without departing from the principles of the invention, some improvement and modification can also be carried out to medication coat of sacculus of the present invention and preparation method thereof, but these improve and modification also falls in the scope of the claims in the present invention request protection.