JPH04176459A - Wound treating material of eye comprising chitin film - Google Patents

Abstract

PURPOSE:To heal wounds quickly by using a wound treating material for eyes comprising a hemispherical transparent chitin film to achieve a higher adhesiveness to the eyes while protecting the eyes without stimulation. CONSTITUTION:Chitin is dissolved into a solvent to prepare a solution. The solution is applied on a spherical surface requiring a desired curvature radius and then, the solvent is removed as intact or after replaced with other non- solvent material, the solvent is removes. It is desired that a molded product obtained by the removal of the solvent or the non-solvent material is washed sufficiently by water, alcohol or the like to remove the solvent or the non- solvent material throughly. After the washing, the molded product is dried and released from a spherical mold to be prepared in a necessary size according to eye balls. The film thus obtained is sterilized by an autoclave or ethylene oxide gas to be mounted on the eyes of a patient. It is used effectively for as means for healing wounds of eye such as operation wounds or the like after the treatment of conea damaged by a contact lens or cataract.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an eye wound treatment material comprising a chitin film.

(Prior Art) In recent years, the chances of injury to the eye have increased. For example, there are wounds that occur as a result of wearing contact lenses. Not limited to hard and soft contact lenses.

The lens is placed so that it fits snugly over the cornea, which covers the surface of the eye. However, if you leave the lenses on for a long time or if dirt gets between the lenses and your eyes, it can damage the cornea and often cause severe eye pain. Furthermore, in the treatment of cataracts, rapid healing of wounds after intraocular lens surgery is also desired.

As a treatment for these wounds that occur within the eye.

The conventional method of healing is to apply ointment to the wound and wear an eye patch to prevent dirt from entering. However, treatment is complicated and healing takes a long time.

The method was not always sufficient. Additionally, during treatment, the patient was unable to see clearly due to the eyepatch, making it an inconvenient period for the patient.

On the other hand, collagen lenses (manufactured by Bausch & Lomb, USA) are available as a method to solve this problem.

This circular lens is made by extracting collagen from the sclera of the white part of a pig's eye.It is a semi-permeable membrane, allowing you to see during treatment and is said to cause less pain. However, a major drawback is that since it is a protein, it has antigenicity. The eyes are particularly sensitive to foreign substances, and often become irritated, especially when they are antigenic.

Therefore.

Collagen lenses have also not always been sufficient as lenses for the purpose of healing wounds in the eye.

The present invention is aimed at protecting the eye from wounds, and has good adhesion to the eye, good wound retention, and transparency.

The purpose is to provide a highly safe film.

(Means for Solving the Problems) As a result of intensive research to achieve the above object, the present inventor discovered that a film made of chitin is good for protecting eye wounds, and arrived at the present invention. This is what I did.

In other words, the gist of the present invention is an eye wound treatment material comprising a hemispherical transparent chitin film.

The present invention will be explained in detail below.

Chitin is poly(N-acetyl-D-glucosamine) obtained by treating the exoskeleton of crustaceans, insects, etc. with hydrochloric acid and caustic soda to remove ash and protein substances, or this poly(N-acetyl-D-glucosamine). D-glucosamine) is a deacetylated product obtained by treating it with a concentrated alkali (the degree of deacetylation ranges from several % to 100%),
Among these, those that have a high degree of deacetylation and are soluble in acids are particularly called chitosan.

The degree of deacetylation herein refers to a value measured by the following method.

Approximately 2 g of the sample is placed in 200 ytfl of a 2N aqueous hydrochloric acid solution and stirred at room temperature for 30 minutes. Then, after filtering through a glass filter to remove the hydrochloric acid aqueous solution.

The mixture was poured into 2001d methanol and stirred for 30 minutes. This is further filtered through a glass filter.

Pour into 200ml of fresh methanol.

Stir for 30 minutes. This washing operation with methanol was repeated 4 times.
After repeating several times, air dry and vacuum dry.

Next, about 0.2 g of the mixture was accurately weighed, placed in a 100-sized Erlenmeyer flask, and 40 d of ion-exchanged water was added thereto, followed by stirring for 30 minutes. Next, this solution is subjected to neutralization titration with a 0.1N aqueous sodium hydroxide solution using phenolphthalein as an indicator.

The degree of deacetylation (A) is determined by a linear equation.

However, a is the weight of the sample (g), and f is 0. IN - titer of the caustic soda aqueous solution, b is the titer (g) of the 0.1N - caustic soda aqueous solution.

The chitin used in the present invention is such chitin, deacetylated chitin, or chitosan.

Furthermore, it also includes derivatives in which the 10H group, -CH, OH group, or -NH2 group of the glucosamine residue of chitin or chitosan is esterified, etherified, carboxymethylated, hydroxyethylated, or 0-ethylated. It can be done. In producing these, highly purified products with low ash and protein content are preferred. In addition, these chitins can be combined with other polymers such as cellulose. It may be used in combination with other polymers such as polyvinyl alcohol and collagen.

The chitin film used in the present invention is molded from these chitins and is a hemispherical body with a suitable radius of curvature that can be attached to the eyeball, and does not generally refer to contact lenses used for vision correction. That is, it does not have optical properties like convex and concave lenses. Therefore, the shape is 10-20mm in diameter and 0.03-0.0mm in thickness.
It means a film-like molded product with a thickness of about 3 inches.

The method for creating the chitin film used in the present invention is as follows:
Wet molding can be used. In other words, a solution is created by dissolving chitin in a solvent, and after applying it to a spherical shaped surface that requires the desired radius of curvature, the solvent is removed as is, or it is replaced with another non-dissolving solution and then the solvent is removed. .

The solvent used to create the chitin solution varies depending on the type of chitin. For example, in the case of chitin with a low degree of deacetylation, it is dissolved in a mixture of trichloroacetic acid and a halogenated hydrocarbon, dimethylacetamide, or a mixture of N-methylpyrrolidone and lithium chloride. Chitin with a high degree of deacetylation, such as chitosan, is generally dissolved in an aqueous solution of acetic acid. At this time, especially in the case of chitosan, since the resistance to water is low, after the molded body is created.

In order to increase this, it is preferable to carry out acetylation with acetic anhydride or insolubilization treatment with glutaraldehyde or the like.

The molded body obtained by removing the solvent and non-solvent is thoroughly washed with water or alcohol.

Preferably, the solvent and non-solvent are sufficiently removed.

After washing, the molded body is dried, removed from the spherical mold, and made into the required size depending on the eyeball. The obtained film is used by attaching it to the patient's eye after being sterilized by autoclaving or ethylene oxide gas, and it is used to heal wounds on the eye such as the cornea injured by contact lenses and the surgical side after cataract treatment. It is effectively used as a means for

(Examples) The present invention will be explained in more detail below using examples.

Example 1 Crude chitosan powder (Shin Nihon Kagaku type) was heat-treated with a 3-7v% caustic soda aqueous solution at 90°C for 3 hours to remove the protein contained therein. The obtained purified chitosan was a white powder, and the degree of deacetylation was 88%.

This powder was dissolved 4 wt % in a 3 wt % acetic acid aqueous solution at room temperature to obtain a transparent solution. This solution has a radius of curvature of 8II
Apply to a thickness of 60 mm on the stainless steel curved surface of Ill.
The solvent was removed by drying at °C. After washing with methanol, it was further treated with 5 wt% acetic anhydride at 60°C for 2 hours. Its degree of deacetylation was 46%. Washed again with methanol and dried. What was removed from the stainless steel curved surface was a transparent hemispherical film with a thickness of 0.06 mm.

When this film was attached to a patient whose cornea was inflamed due to contact lenses, it showed good adhesion, and as a result, the inflammation healed after two weeks.

Example 2 Chitin powder (Shin Nippon Chemical type; degree of deacetylation is 3.5%)
, 25°C dimethylacetamide and lithium chloride 9:
Solution viscosity when dissolved at 0.2 wt% in 1 mixed solution is 350
centipoise) was dissolved in a 9:1 mixture of dimethylacetamide and lithium chloride at 3 wt % to prepare a clear solution. After sufficiently removing insoluble matter by filtration, it was applied to a stainless steel curved surface with a radius of 9 curvature of 7 mm to a thickness of 2.5 mm, solidified with dimethyl formaldehyde, and then 90°
It was dried at C to remove dimethylformamide. What was obtained was a transparent film with a thickness of 0.07+im.

After sterilization, this was applied to a patient after cataract surgery, and healing was completed in 4 days, which was faster than normal ointment and gauze treatment.

(Effects of the Invention) The eye wound treatment material made of the chitin film of the present invention exhibits good adhesion to the eye, protects the eye without irritating it, and allows the wound to heal quickly.

Claims (1)

[Claims] (1) An eye wound treatment material consisting of a hemispherical transparent chitin film.