CN1059129C - Wound surface protective film and preparation method thereof - Google Patents

Abstract

The invention relates to a medical material, in particular to a protective film (or artificial skin) suitable for covering wounds and a preparation method thereof. It uses silk as the main raw material, and the silk is degummed, dissolved, purified, dried to form a film, Packaging, disinfection and other processes, processed into silk fibroin film. Clinical application shows that the protective film is sterile and non-toxic, and because the amino acid composition of silk fibroin is similar to the collagen that constitutes human skin, the wound protective film made of it has good tissue compatibility with the human body , and at the same time has good water permeability and good adhesion to the wound.

Description

A kind of wound protective film and preparation method thereof

The invention relates to a medical material, in particular to a protective film (or artificial skin) suitable for covering wounds and a preparation method thereof.

As we all know, when human skin is damaged due to burns or trauma, the natural protective barrier disappears, body fluids will leak out, a large amount of protein and electrolytes in the body will be lost, super high metabolism, infection, and even wound sepsis and systemic invasive infection will occur , endangering human life, so the wound should be covered as soon as possible. In the treatment of burn patients, the wound protective film is suitable for covering superficial burn wounds, promoting wound healing, or protecting deep burn wounds, waiting for skin grafting. At present, there are many types of wound protective films developed at home and abroad. Generally speaking, wound protective films are mainly composed of film-forming materials and additives. In terms of film-forming materials for preparing wound protective films, there are mainly synthetic polymer materials, such as polyurethane, silicon organic polymer compounds, etc.; natural polymer materials, such as collagen, chitosan, etc. In the film-making process, the additives added are mainly plasticizers, release agents, etc., and certain pharmaceutical ingredients, such as antibacterial drugs or other special-purpose drugs, can also be added. In May, 1989, "Pharmacy" (Second Edition) published by People's Medical Publishing House, in the section "Film Agent" of the fourteenth chapter, just discloses using PVA as the film-forming material, glycerin etc. as the plasticizer, liquid The preparation method of general film preparations in which paraffin wax etc. are film release agents, and discloses the film preparation examples of adding drugs such as diphenethyl hydrochloride, atropine sulfate and the like. Chinese patent "Artificial Skin and Its Manufacturing Technology" (CN1071085) also discloses an artificial skin made of chitin as a film-forming material, added with additives such as higher monohydric alcohols, higher fatty acids, and palmitin, through a mixed reaction. Technology. For the film-forming materials for making wound protective films, whether they are synthetic polymer materials or natural polymer materials (except collagen), since they are not proteins similar to human skin composition, the wound surface made of these materials In clinical application, the protective film still has some deficiencies in some aspects, for example, it cannot have good water and vapor permeability and adhesion to the wound surface at the same time. Therefore, people are constantly looking for more ideal materials for making wound protective films.

The purpose of the present invention is to provide a wound protection film with good compatibility with the human body and a preparation method thereof for the deficiencies of the prior art.

The wound protective film of the present invention is composed of film-forming material and additives, and is characterized in that said film-forming material is silk fibroin made from silk, and the content of silk fibroin in the wound protective film is 80-90%, the composition of silk fibroin is mainly composed of tyrosine and alanine, which is similar to the protein composition of human skin.

The preparation method of the wound protective film of the present invention is carried out according to the following procedures: 1. Degumming: heating the silk in the degumming solution to remove the sericin on the periphery of the silk to obtain silk fibroin; The silk fibroin is heated and dissolved in a solvent to make a silk fibroin mixed solution; 3. Purification: dialyze, filter and purify the silk fibroin mixed solution to obtain a pure silk fibroin solution; 4. Film formation: in pure silk fibroin Add additives to the silk fibroin solution, mix evenly, pour into the film-forming mold, and dry the silk fibroin film with hot air at 40-60°C; 5. Packaging and disinfection: process the silk fibroin film into certain After meeting the specifications, pack and sterilize to obtain the finished wound protective film.

The wound protective film of the present invention uses silk as the main raw material, and silk is a relatively pure natural protein, and the amino acid composition of silk fibroin contains a large amount of tyrosine and alanine, which are different from those that constitute human skin. Collagen is similar, so the wound protective film made of it has good tissue compatibility with the human body, is sterile and non-toxic, and has good water and vapor permeability and adhesion to the wound at the same time; The raw material is very abundant in our country, and the process of making wound protection film with it is simple, so the price of the finished product is relatively low; at the same time, because this kind of wound protection film is a dry film, it can be stored for a long time at room temperature without mildew, so It is convenient to store, transport and use.

The wound protective film made by the present invention has been applied to more than 150 wounds in clinical practice of burns. After covering, the wound protective film adheres tightly to the wound of human body, no infection occurs in one case, and the healing is uniform and the curative effect is good. In addition, since the wound protection film is completely transparent, the healing process of the wound can be observed very clearly and conveniently during use, which greatly reduces the pain of patients during treatment. The positive significance of the present invention can also be illustrated by comparing with various wound protective films, see Table 1. In Table 1, the symbol "-" means "No", the symbol "+" means "Yes", and the symbol "*" means that this item is the most important clinically required performance indicator.

The present invention is implemented by following examples:

Example 1:

1. Put 1 kg of silk into 40 liters of sodium carbonate aqueous solution with a concentration of 0.5‰, and boil for 0.5 hours. Repeat the treatment twice to remove all the sericin around the silk to obtain pure refined silk (ie silk fibroin).

2. Put the obtained silk fibroin into an oven and dry it at 110°C. The dried silk fibroin was heated and dissolved at 80°C with 4 liters of calcium chloride-water-ethanol solution with a molar ratio of 1:8:2 to form a silk fibroin mixed solution, and then kept for 0.5 hours.

3. Using cellophane film as dialysis material, dialyze the obtained silk fibroin protein mixed solution against water to remove calcium chloride and ethanol, and then filter with multi-layer degreasing gauze to obtain pure silk fibroin protein solution.

4. Add additives compounded by various drugs to the obtained pure silk fibroin solution, mix evenly to form a film-forming stock solution, inject it into a plastic film-forming mold, and drum it in a dryer at 50°C Air-dried to form a film with a thickness of about 0.05 mm.

5. Cut the silk fibroin film into a wound protective film with a size of 10×16 cm, pack and seal it with a double-layer plastic bag, and then sterilize it with gamma ray irradiation to obtain the finished product.

Example two:

1. Take 2 kg of leftover cocoon silk as raw material, put it into 80 liters of sodium carbonate aqueous solution with a concentration of 0.5‰, and boil for 0.5 hour. Repeat the treatment twice to remove all the sericin around the silk to obtain pure refined silk (ie silk fibroin).

2. Put the obtained silk fibroin into an oven and dry it at 105°C. The dried silk fibroin is boiled and dissolved with 8 liters of 50% calcium chloride aqueous solution to prepare a silk fibroin mixed solution.

3. Using cellophane film as dialysis material, dialyze the obtained silk fibroin protein mixture solution against water to remove calcium chloride, and then filter with multi-layer degreasing gauze to obtain pure silk fibroin protein solution.

4. Add additives compounded by various drugs to the obtained pure silk fibroin solution, mix evenly to form a film-forming stock solution, inject it into a plastic film-forming mold, and drum it in a dryer at 55°C. Air-dried to form a film with a thickness of about 0.05 mm.

5. Cut the silk fibroin film into a wound protective film with a size of 20×16 cm, pack and seal it with a double-layer plastic bag, and then sterilize it with γ-ray radiation to obtain the finished product.

According to the procedures described in the above examples 1 and 2, a silk fibroin film made of silk as the main raw material can be obtained, wherein the silk fibroin content is about 90%, and the film is soft, transparent and sterile. Non-toxic, it becomes a wound protective film that has good compatibility with the human body, and has good water and vapor permeability and adhesion to the wound.

Table 1: Performance comparison of various wound protective films Wound protective film name patient pain Time-consuming operation ^* Water and vapor permeability ^* Adhesion to wound surface Strength and toughness transparency Polyurethane film, silicone film (ultra-thin, foam) - - +++ - +++ + Chitin, chitosan film - - +++ ++ + collagen membrane - - ++++ +++ - - Methyl cyanoacrylate film - +++ ++ +- ++ + Methacrylic Compound Spray +++ + ++ +- + ++ Split skin (human skin, pig skin) - - +++ +++ +++ - silk fibroin film - - +++ +++ ++ +++

Claims (3)

1. a Wound surface protection film is made up of filmogen, additive, it is characterized in that described filmogen is is the fibroin albumen that raw material is made with silkworm silk, and the content of fibroin albumen in Wound surface protection film is 80～90%.

2. method for preparing Wound surface protection film as claimed in claim 1 is characterized in that preparation section is as follows:

A. silkworm silk is heated in degumming liquid, slough peripheral sericin, obtain fibroin albumen;

B. fibroin albumen is dissolved in solvent;

C. the fibroin albumen mixed solution that obtains is filtered, purifies;

D. in the pure silk fibroin protein solution that obtains, add additive, drying and forming-film.

3. the preparation method of Wound surface protection film according to claim 2 is characterized in that among the described operation d, and the temperature of drying and forming-film is 40～60C °.