SUMMERY OF THE UTILITY MODEL
The utility model aims at providing an artificial blood vessel that can puncture immediately for dialysis patient, just can satisfy the dialysis condition after implanting internal 24-48h, can dialyze the puncture, need not do anticoagulant medicine preliminary treatment to artificial blood vessel when implanting simultaneously, and the anticoagulation coating of having certainly can satisfy the antithrombotic, prevent the inner membrance hyperplasia, further satisfies clinical application.
In order to achieve the above purpose, the utility model provides a technical scheme does:
an immediate puncture dialysis type nanofiber artificial blood vessel, the tube wall has an inner layer, an outer layer and a nonporous compact coating positioned between the inner layer and the outer layer;
the inner layer is of an electrostatic spinning nanofiber structure; an anticoagulant coating is fixed on the inner wall of the inner layer;
the outer layer is of an electrostatic spinning nanofiber structure;
the nonporous compact coating is internally wrapped with a bending-resistant fold ring, the bending-resistant fold ring is a spiral winding wire with a spiral structure, and the spiral winding wire is spirally wound on the inner layer.
Preferably, the inner diameter of the instant puncture dialysis type nanofiber artificial blood vessel is 2-8 mm.
Preferably, the thickness of the nanofibers of the inner layer is 100-600 microns. The inner layer is made of a high polymer material and polyamino polymer mixed material or a single high polymer material. The inner layer is a nano fiber tube prepared by the electrostatic spinning/spraying method of the first spinning solution.
The first spinning solution is prepared by dissolving a high polymer material and a polyamino polymer or a single high polymer material in an organic solvent according to a mass ratio of (1-9): 1, wherein the total mass volume concentration of the high polymer material and the polyamino polymer or the single high polymer material is 10-30%.
Specifically, the anticoagulant coating is formed by grafting an anticoagulant substance on the inner wall of the nanofiber tube in a covalent grafting mode.
Specifically, the nonporous dense coating has no pores and no delamination.
Preferably, the thickness of the non-porous dense coating is 10-1000 microns. The nonporous compact coating is made of a high polymer material. The nonporous dense coating is formed by applying a spray solution to the outer surface of the inner layer.
The spraying solution is prepared by dissolving a high polymer material in an organic solvent, and the mass volume concentration of the high polymer material is 1-20%.
The coating mode comprises dip coating, cladding coating, vapor deposition and ultrasonic atomization spraying.
Preferably, the diameter of the spiral-wound wire is 0.1 to 1 mm, the pitch is 1 to 6 mm, and the length of the spiral-wound wire is 40 to 5000 mm.
Specifically, the spiral wound wire is prepared by the following method: the melt-extruded wire rod with the diameter of 0.1-1 mm is wound on a stainless steel screw rod with the screw pitch of 1-8 mm, and is fixed into a spiral winding wire with a spiral structure at the high temperature of 100-200 ℃. Wherein the material of the wire is selected from polyurethane, siloxane-terminated polycarbonate, polyethylene terephthalate, or perfluoroethylene propylene copolymer.
Specifically, the partial section of the artificial blood vessel is provided with a bending-resistant ring which forms a bending area of the artificial blood vessel. The regional bending can conveniently be bent according to clinical needs and does not influence the patency of blood, for example is used for arteriovenous fistulization, and does not influence the patency of blood.
Preferably, the outer layer nanofiber has a thickness of 100-500 microns. The outer layer is made of a high polymer material. The outer layer is an electrostatic spinning nanofiber structure which is formed on the outer surface of the nonporous compact coating by a second spinning solution through an electrostatic spinning/spraying method.
The second spinning solution is prepared by dissolving a high polymer material in an organic solvent, and the mass volume concentration of the high polymer material is 1-20%.
The utility model provides an artificial blood vessel, inlayer nanofiber are made with two kinds of different polymers, and sclausura compact layer (middle level) is made by the polymer of one, and outer nanofiber is made by the polymer of one, and the parcel has the bending resistance to roll over the ring in the sclausura compact layer.
The utility model aims at providing a preparation method of instant puncture dialysis type nanofiber artificial blood vessel, its characterized in that, concrete step is as follows:
(1) preparing the first spinning solution into a nano fiber tube (defined as an inner layer) with the thickness of 0.1-1.2 mm by adopting an electrostatic spinning/spraying method;
the first spinning solution is prepared by dissolving a high polymer material and a polyamino polymer or a single high polymer material in an organic solvent according to a mass ratio of (1-9): 1, wherein the total mass volume concentration of the high polymer material and the polyamino polymer or the single high polymer material is 10-30%;
(2) coating the spraying solution on the outer surface of the nanofiber tube to form a nonporous compact coating with the thickness of 0.01-10 mm; winding the bending-resistant folding ring on the outer wall of the nanofiber tube coated with the nonporous compact coating through a spiral winding device, and continuously coating the spraying solution to wrap and fix the bending-resistant folding ring to obtain the nanofiber tube with the bending-resistant folding ring;
the spraying solution is prepared by dissolving a high polymer material in an organic solvent, wherein the mass volume concentration of the high polymer material is 1-20%;
the preparation method of the bending-resistant folding ring comprises the following steps: winding a wire rod with the diameter of 0.1-1 mm, which is extruded by melting, on a stainless steel screw rod with the screw pitch of 1-8 mm, and fixing the wire rod into a spiral winding wire with a spiral structure at the high temperature of 100-200 ℃, thus obtaining the anti-bending ring; the length of the spiral winding wire is 40-500 mm;
(3) preparing a nanofiber layer (defined as an outer layer) with the thickness of 0.1-0.5 mm on the outer surface of the nanofiber tube with the bending-resistant corrugated rings by adopting an electrostatic spinning/spraying method for the second spinning solution; the second spinning solution is prepared by dissolving a high polymer material in an organic solvent, and the mass volume concentration of the high polymer material is 10-30%;
(4) and grafting an anticoagulant substance on the inner wall of the nanofiber tube in a covalent grafting mode to form the anticoagulant coating.
The polymer materials synthesized by electrostatic spinning in the steps (1), (2) and (3) include, but are not limited to, polyurethane (aromatic, aliphatic, etc.), siloxane-terminated polycarbonate (aliphatic, aromatic), nylon, polytetrafluoroethylene, polyvinyl alcohol, polylactic acid, polyethylene, polycaprolactone; the natural polymer material comprises chitosan, collagen, silk fibroin and cellulose;
the polyamino polymer in the step (3) includes but is not limited to polydopamine, multi-arm amino-terminated polyethylene glycol, polyethylene imine, polypropylene imine, and polyimide chloride;
the organic solvent in the steps (1), (2) and (3) is one or more selected from hexafluoroisopropanol, acetone, tetrahydrofuran, dichloromethane, toluene and N, N-dimethylformamide;
the material for bending-resistant ring in step (6) includes, but is not limited to, polyurethane (aromatic, aliphatic, etc.), siloxane-terminated polycarbonate (aliphatic, aromatic), polyethylene terephthalate (PET), and perfluoroethylene propylene copolymer (FEP).
The electrostatic spinning conditions in the steps (4) and (6) are that the speed of a propulsion pump is 0.5-5ml/h, the voltage is-3.00 kv- +20kv, the moving speed of a platform is 10-100mm/s, the acceleration and deceleration time of the platform is 100 plus 9000mms, the environmental temperature is 20-40 ℃, and the relative humidity is 10-70%.
The coating process in the step (6) includes but is not limited to dip coating, cladding coating, vapor deposition, ultrasonic atomization spraying.
Compared with the prior art, the utility model discloses there is following beneficial effect:
(1) the utility model provides an instant puncture type nanofiber artificial blood vessel, the inner wall and the outer wall of the artificial blood vessel prepared by electrostatic spinning are nanofibers, which can fully simulate the structure of natural extracellular matrix, provide good environment for the growth, adhesion and migration of cells, and the higher porosity is favorable for the exchange of nutrient substances; the nanofiber has a large specific surface area, can increase the drug loading rate of anticoagulant substances, and has good elasticity and compliance.
(2) The utility model provides a pair of instant puncture type nanofiber artificial blood vessel has set up a nonporous compact layer between skin and inlayer, and the coating on nonporous compact layer has strengthened artificial blood vessel's antiseep effect and has promoted mechanical properties's promotion. The compact layer has higher elasticity, when the artificial blood vessel is punctured by a puncture needle or a suture needle, the leakage of blood can be prevented, along with taking out the needle, the puncture hole position can be automatically healed, the hemostasis time is shortened, the thrombus formation at the puncture position is reduced, and the service life is prolonged.
(3) The utility model provides a pair of instant puncture type nanofiber artificial blood vessel, the parcel has the bending resistance to roll over the ring in the fine and close coating of sclausura, and the bending resistance is the spiral winding silk that has helical structure, is the heliciform along artificial blood vessel's length direction and twines on the inlayer and form, has increased artificial blood vessel's bending resistance. The bending-resistant folded ring can keep the pipe diameter of a bending area formed by the spiral structure consistent with the pipe diameter of an unbending area, and the blood smoothness is improved. Especially to the bending region of ordinary artificial blood vessel, lead to the easy seepage of puncture hole because of self is tensile, and the utility model discloses an anti-bending is folded the ring and is increased the regional elastic deformation performance of buckling, and anti-bending is folded the ring and is cooperated the sclausura compact layer and enable the regional quick automatic healing of puncture hole of buckling, effectively prevents the seepage of the regional puncture hole of buckling.
(4) The utility model provides a pair of instant puncture type nanofiber artificial blood vessel, ethanol soak and high temperature treatment, make outer fibre compacter, and can withstand stronger mechanical frictional force.
(5) The utility model provides a pair of instant puncture type nanofiber artificial blood vessel, the blood vessel inner wall is through covalence grafting's method with anti-freezing material grafting to the internal surface, the method of physical deposition, ionic bond compares, the utility model discloses a combination is more firm, before artificial blood vessel forms endothelialization, can exert anti-coagulation characteristic, reduces thrombus and narrow formation, prolongs artificial blood vessel's live time.
(6) The utility model provides a pair of instant puncture type nanofiber artificial blood vessel, preferred as vascular graft, more preferred is used for the vascular graft of kidney dialysis.