CA1123735A - Biologically active polyamide net and method of obtaining it - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE:
The present invention is concerned with a polyamide net or mesh suitable for surgical implantation into the human or an animal body and a method for obtaining the same. The net comprises from 0,1 to 5% by weight of an anti-bacterial preparation in combination with a knit of polyamide fibres 5 to 10 Tex. thick and with up to 500 twists per meter of fibre. The dimensions of the cells of the net are of 1,0 - 1,5 mm x 1,2 - 2,0 mm.

Description

The invention relates to a biologically active polyamide net or mesh for implanting into the human or an animal body by means of surgery and to a method of obtaining it.
Polyamide, polyester, polypropylene, polyethylene, polytetrafluorethylene, metal and other nets are already known which, when implanted into the human body, are in most cases rejected as a result of the protective immune reaction of the r human organism.
Materials are known based on carboxymethylcellulose and polyvinylalcohol fibres, which are resorbed by the human organism but theyare not suitable for supporting or making barriers between human organs. This is because after their resorption the treated area becomes weaker than the other tissues and, in many cases, is torn.
Methods are known for obtaining biologically active polyamide fibres and nets. The most effective of these r methods involves treating polyamide fibres with an aqueous solution of K-salt of 5-nitro-8-oxyquinoline or 5,7-dichlor-8-oxyquinaldine at high temperature for half an hour. A general drawback of the already known methods is that they do not separate the mixtures and the low-molecule compounds contained in the polyamide fibres. The nets obtained by these methods, when transplanted into the human body, often cause suppuration and are incompatible with living tissue.
An object of the invention is to provide a biologi- I
cally active polyamide net, compatible with human tissue, and which is sufficiently strong while tissue healing takes place, as well as providing a method for producing the net.
The essence ofthe invention is the following:
A polyamide net knit of 3 to 6 fibres is used for implanting into the human or an animal body. For the knitting >3735 are used polyamide fibres of 5 to 10 Tex thick, preferably of about 7,6 Tex and with up to 500 twists, preferably about 350 twists per meter of fibre. Preferably, the net is composed of unit cells whose dimensions are from 1,0 - 1,5 mm x 1,2 -

2,0 mm. The polyamide net thus formed is elastic, hygroscopic and is very strong.
In order to be accepted by the human body, the so described net is preferably subjected to the following treat-ment: it is twice treated with non-ionogenic washing means, for example washing means based on alkylphenylpolyglycolether for 5 to 3 min, preferably for 15 min, at a temperature of 20 to 90C, preferably 90C. Immediately afterwards the net is treated twice, firstly with boiling water from 5 to 30 min, preferably for 15 min and then with water having temperature from 1 to 30C, preferably 15C. Then successively follows treatment with alcohol or acetone for 5 to 30 min, preferably for 15 min at room temperature under agitation. The material is then twice rinsed with distilled water from 10 to 50C, is drained up to 50~ residual humidity and is then treated at a temperature of 20-90C for 5 to 120 min with a solution of an antibacterial preparation - for example, one of the antibiotics, or derivatives of 8-oxyquinoline, 8-oxyquinaldine, aromatic or aliphatic amines, nitrofuran derivatives, metal salts, quaternary ammonium compounds etc., is then rinsed with water at 5 to 30C for 5 to 30 min, preferably 15 min and is dr~ed at 20-100C up to residual humidity of 2-5~.
The preferred basic quality of the biologically active net is that it contains from 0,1 to 5~ of an anti-bacterial preparation, which is connected with the polyamide net so that it can endure for a long time. This feature makes the net usable without sterilization and without using any special covering material. It may be directly applied ~1~373~

without danger of any septic reaction. The slow resorption of the net by the organism makes the material strong enough during the period of tissue repair.
The method of the invention for obtaining of bio-logically active net is easily performed without needing any special techniques.
The invention may be illustrated by the following non restrictive examples: r Example 1. A 100 g polyamide net, knit of polyamide fibres of 7,6 Tex. and 360 twists per meter, dimensions of the cells 1,2 - 1,3 mm x 1,2 - 1,3 mm, is twice treated with methylphenylpolyglycolether for 15 min at a temperature of 90C.
After that it is twice treated: firstly, with boiling water for 15 min and next with water having temperature of 20C for 15 min. Then follows treatment with methy~ alcohol or acetone for 15 min at room temperature and with agitation. The material is twice rinsed with distilled water having a temperature of 20C for 15 min, then is drained up to 50~ residual humidity and is treated at a temperature of 70C for half an hour with an aqueous solution of K-salt of 5-nitro-8-oxyquinoline witha concentration ofl g/l. Then it is washed with water having temperature of 90C and is dried at 50C until 4% residual humidity remains.
- Example 2. The treatment and conditions set out in Example 1 are repeated using the same polyamide net, but instead of the potassium salt of 5-nitro-8-oxyquinoline there is used an alcoholic solution of 5,7-dichlor-8-oxyquinaldine with a 1 g/l concentration.
Example 3. The treatment and conditions set out in example 1 are repeated using the same polyamide net, but instead of the K-salt of 5-nitro-8-oxyquinoline there is used a solution in dimethylformamide with a concentration of 1 g/l

-3-11.23'735 of N-5-nitro-2-furfurylidene 3-amino-2-oxazolidone.
Example 4. The treatment and conditions set out in Example 1 are repeated using the same polyamide net, but instead of the K-salt of 5-nitro-8-oxyquinoline there is used a solution of N-5-nitro-2-furfurylidene-p-phenetidine in ethyl alcohol with a concentration of 2 g/l.
Example 5. The treatment and conditions set out in Example 1 are repeated using the same polyamide net, but instead of the K-salt of 5-nitro-8-oxyquinoline there is used an aqueous solution of an alkyldimethylbenzylammonium chloride with 8 to 18 carbon atoms in the alkyl group, and at a concentration of 10 g/l.
; Example 6. The treatment and conditions set out in Example 1 are repeated using the same polyamide net, but instead of the K-salt of 5-nitro-8-oxyquinoline there is used a water-alcohol (60:40) solution of N-cetylpyridine bromide with a concentration of 5 g/l. r Example 7. The same sequence of operations is done as in Example 1, but the net is not dried: instead it is treated with a saturated solution of silver nitrate, is rinsed thrice for 15 minutes each time with distilled waterat 15C
and then is dried at a temperature of 50C until 4~ residual humidity is reached.
The nets obtained according to each of the above Examples, as well as the untreated polyamide net, are inserted into the body of a test animal. The nets made in accordance with the above seven examples do not provoke a rejection reaction, while the untreated net causes suppuration.

Claims (2)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A polyamide net or mesh suitable for surgical implantation into the human or an animal body, having a bio-logical activity determined by the contents of 0,1 to 5% anti-bacterial preparation, which is formed of polyamide fibres 5 to 10 Tex. thick and with up to 500 twists per meter of fibre and dimensions of the cells of the net are from 1,0 -1,5 mm x 1,2 - 2,0 mm.

2. A method of obtaining of biologically active polyamide net or mesh for implantation into the human or an animal body, according to claim 1, characterized in that the net or mesh is twice treated with a non-ionogenic solvent for 5 to 30 minutes at a temperature from 20 to 90°C, after which it is twice treated, firstly wigh boiling water from 5 to 30 min, then with water having temperature from 1 to 30°C, after that it is treated with alcohol or acetone for 5 to 30 min at room temperature and under agitation, after which the net or mesh is washed with distilled water, is drained up to 50% residual humidity and is treated at 20 to 90°C temperature for 5 to 120 min with a solution of an antibacterial preparation, is washed with water having temperature of 5 to 30°C for 5 to 30 min and is dried at 20 to 100°C up to 2-5%
residual humidity is reached.