CZ307458B6 - A multilayer wound cover with an active layer and a method of its manufacture - Google Patents

Abstract

The active layer attached to the conventional textile carrier layer intended for medical devices and wound covers is made up of a modified nanofibrous nanostructure based on biodegradable and/or biocompatible polymers of natural and/or synthetic origin, which is capable of binding the amino derivative of β-cyclodextrin by an ionic bond after a previous physical modification by plasma resulting in chemical functionalization with a predominance of carboxyl groups. It contains an encapsulated or post-binding encapsulated active substance, in particular of a character of healing and/or antiseptic agents and/or drugs for targeted therapy of a specific wound treatment, which are released into the wound environment gradually and in a controlled manner.

Description

The present invention relates to a multi-layer wound cover with an active layer comprising at least one carrier layer and at least one active layer based on nanofibres to which cyclodextrin molecules with encapsulated low molecular weight substances are bound. Furthermore, the invention relates to a method for manufacturing this multilayer wound cover.

BACKGROUND OF THE INVENTION

At present, the principle of cyclodextrin binding to a polymer matrix for the purpose of using such a modified polymer as a drug carrier or fragrance is already known in many applications.

E.g. two Chinese patents CN 102178640 and CN 103266424 address the modification of a polymeric carrier (matrix) by direct addition of cyclodextrin or a suitable cyclodextrin derivative directly to the polymeric matrix. This results in the bulk modification of the polymer by cyclodextrin. The disadvantage of this solution is that most of the cyclodextrin molecules remain in the polymer volume and the use of cyclodextrin cavities as a release of the encapsulated active substances, or vice versa, as a sorbent is therefore impossible or considerably limited.

This drawback is solved by the invention according to PCT International Application WO 2012150459, which utilizes the formation of a covalent bond between a suitable cyclodextrin derivative and the surface of a plasma-treated polymer. This creates a permanent chemical bond between the carrier polymer and the cyclodextrin. The disadvantage of this solution, however, is precisely the formation of a permanent chemical bond, which brings a new chemical character to the original material, and especially in the case of use in the field of medical applications, this fact can lead to new toxicological and biodegradation properties of such material.

SUMMARY OF THE INVENTION

To a large extent, the multilayer wound cover with at least one carrier textile layer of conventional fabric and a nanofibers sheet active layer deposited thereon contributes to the above-mentioned deficiencies.

SUMMARY OF THE INVENTION The multilayer wound cover can be produced by first electrostatically spinning the active layer as a layer of nanofibres of biodegradable and / or biocompatible polymers, preferably polylactide, acetylcellulose, polyvinyl alcohol and / or polyurethane and deposited on a carrier a layer of conventional fabric. Subsequently, the active layer, together with the carrier fabric, is subjected to plasma treatment, preferably using a diffuse coplanar barrier surface discharge for functionalization. Further, the active layer together with the carrier fabric is sprayed with continuous rewinding of either an aqueous or aqueous-alcohol solution of the amino derivative β-cyclodextrin with the encapsulated active substance Berberin or the solution of the amino derivative Bcyclodextrin followed by a solution of the active substance Berberin, which is encapsulated into cavity of the .beta.-cyclodextrin derivative and then the excess active compound is eluted. This is followed by drying the resulting product with the ion-bound amino derivative of β-cyclodextrin, adjusting it to commercial size and sterilizing by gamma irradiation.

Ionically bonded amino derivative of .beta.-cyclodextrin is preferably cyclodextrin derivative comprising two covalently attached amino groups, such as 6 ^I - [2- (2-aminoethylamino) ethylamino] ^{-6-dideoxy-beta-cyclodextrin.}

- 1 GB 307458 B6

The main benefit of the invention is that the amino derivative of β-cyclodextrin is bound to the polymeric nanostructure carrier based on nanofibres from biodegradable and / or biocompatible polymers not by covalent bonding but by ionic bonding. Specifically, for example, an ammonium salt of the corresponding cyclodextrin amino derivative with the corresponding carboxyl derivative of a given polymer is formed on its plasma functionalized surface. This bond, although strong enough to meet the stability requirements of binding the cyclodextrin to the polymeric carrier, also allows - for example, by a slight pH change - the cyclodextrin to be unbound, as well as easier washing away or biodegradation in the biological environment.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The biodegradable nanofibrous wound cover with berberine consists of a carrier layer of biocompatible cellulose-based material and an active nanofibrous layer based on acetylcellulose. It is able to bind the mediator of the active substance based on the cyclodextrin aminoderivative carrying a positive charge, in particular β-β-amino-ethylamino-ethylamino-ω-deoxy-β-cyclodextrin, by means of functionalization predominantly of carboxyl and hydroxyl groups. or release the encapsulated low-molecular-weight active substance, in particular berberine, in the desired manner.

The biodegradable nanofibrous wound cover with berberine in the exemplary embodiment was made as follows: a nanofibrous textile material based on acetylcellulose deposited on a textile backing of a biocompatible cellulose-based material was plasma-treated from the nanofiber side by a diffusion coplanar barrier surface discharge s, corresponding to a material feed rate of 0.75 m / min.

The material thus treated was then exposed to an aerosol of 0.5 wt. aqueous solution of 6 ¹ [2- (2-aminoethylamino) ethylamino] 6'-deoxy-.beta.-cyclodextrin has been encapsulated berberine with a total dose of about 15 ml per 1 m ² at a speed of displacement of 0.75 m / min. The material was then dried in a hot air oven at 80 ° C at a material feed rate of 0.75 m / min.

Example 2

The biocompatible nanofibrous wound cover with salicylic acid consists of a carrier layer of biocompatible material based on polypropylene spunbond and an active nanofibrous layer based on biocompatible polyurethane. It is able to bind the mediator of the active substance, in particular the carboxyl and hydroxyl groups by ionic bonding of the mediator of the active compound based on the aminodivent cyclodextrin bearing positive charge, namely 6- deoxy-6- (N, N, N, N ', N'pentamethyl-1,3-propylenediammonio) -β-cyclodextrin and subsequently encapsulate or release the desired encapsulated low molecular weight active agent, in a particular example salicylic acid.

Nanofibrous textile material based on biocompatible polyurethane deposited on a textile backing of biocompatible material based on polypropylene spunbond was surface treated from the nanofiber side by plasma by means of diffusion coplanar barrier

The surface discharge with an energy of 300 watts for 2 s corresponds to a material feed rate of 0.75 m / min.

The material thus treated was then exposed to an aerosol of 0.5 wt. of an aqueous solution of 6-deoxy-6- (N, N, N, N ', N'-pentamethyl-1,3-propylenediammonio) -β-cyclodextrin with already encapsulated salicylic acid at a total dose of about 15 ml per 1 m ² at a rate of feed 0.75 m / min. The material was then dried in a hot air oven at 80 ° C at a material feed rate of 0.75 m / min.

Claims (2)

A multilayer wound cover with at least one carrier textile layer of conventional fabric and a nanofiber sheet active layer deposited thereon, obtainable by first preparing by electrostatic spinning the active layer as a nanofiber sheet of biodegradable and / or biocompatible polymers, preferably polylactide , acetylcellulose, polyvinyl alcohol and / or polyurethane, deposited on a carrier layer of conventional fabric, then the active layer together with the carrier fabric is subjected to plasma treatment, preferably using a diffuse coplanar barrier surface discharge for functionalization; spraying the carrier fabric with continuous rewinding with either an aqueous or aqueous-alcoholic solution of the amino derivative B-cyclodextrin with the already encapsulated active substance, which is berberine or the solution of the amino derivative Bcyclodextrin, followed by the solution of the active substance Berberine, which is encapsulated into the cavity of the β-cyclodextrin amino derivative, and then the excess active ingredient is washed out, followed by drying the resulting product with the β-cyclodextrin ion-bound amino derivative, adjusting it to commercial size and sterilizing by gamma irradiation. The multilayer wound dressing of claim 1, wherein the ion-bound amine derivative of β-cyclodextrin is a cyclodextrin derivative containing at least two covalently bonded amine groups such as 6 ¹ [2- (2-amino-ethylamino) -ethylamino] -6 ¹ -deoxy- Β-cyclodextrin.