一、General situation of medical non-woven fabric industry
Since the 21st century, especially after SARS in 2003, nonwovens technology has made great progress.With the continuous growth of consumer demand, a complete supply chain system has been formed for the processing of non-woven products, raw material production and equipment manufacturing, especially for the production and application of medical non-woven fabrics.
With the improvement of people's living standard, as well as the improvement of medical and health services, medical non-woven fabric market penetration and consumption gradually increase, while the progress of technology make medical non-woven fabric on technical level, protective function has greatly promoted, the export enterprise production of high-performance, high-quality medical non-woven popular in the United States, Japan, Europe, Oceania and other places, has five medical non-woven most developed markets, in order: the United States, Europe (mainly European countries), Canada, Japan, Australia.According to INDA's data, the global sales of medical non-woven fabrics in 2019 reached 710,000 tons, including 340,000 tons in North America, 230,000 tons in Asia and 140,000 tons in Europe. As the world's largest market for medical non-woven fabrics, North America's market for medical non-woven rolls reached 1.6 billion DOLLARS in 2012.
The development of China's medical textile industry did not enter into a period of rapid growth until 2000. According to the public data, China's medical and sanitary textile industry grew by 25% annually from 2008 to 2019, covering disposable operating clothes, surgical sheets and medical auxiliary materials.It is estimated that the global demand for disposable medical textiles will reach 298 billion US dollars in 2019. China has more than 60,000 hospitals, 130,000 clinics and more than 5 million hospital beds, providing huge development space for disposable medical non-woven fabrics.
The leading products in the medical protection market are disposable surgical suits, cave towels and sterilizing and sterilizing package materials. According to INDA's information,In North America alone, disposable surgical suits, cave towels and their packaging account for 80% of non-woven products. Other varieties, such as disinfection and sterilization bag materials, masks, isolation suits, shoe covers, hats, absorbents, dressings, etc., also have a high proportion of non-woven products.
Medical non-woven fabric types including spun-bonded non-woven, spun-bonded non-woven, melt-blown process spunlace nonwoven, etc., including spun-bonded and melt-blown technology in compound non-woven fabric as typical, common have SMS, SMMS, SMMMS knot 枃, uniform product quality of a material soft, tensile strength and liquid shielding performance is good, its spun-bonded layers composed of continuous filament, have very good breaking strength and elongation, melt-blown layer of continuous superfine fiber of moisture, dust, bacteria, viruses and other barrier for good, after dealing with the antistatic, such as "three anti", simultaneously has the high hydrostatic pressure resistance and good air permeability,Used for manufacturing surgical clothes, surgical holes, surgical bags, sterilization packaging materials, etc.
二、Biocompatibility test of medical non-woven fabrics
People's consciousness in the infection is improving and the development of medical and health care market is rapidly promote the development of medical non-woven fabric, but in people as well as the increasing improvement of the consciousness in the infection, health protection products is also facing a more and more important problem, that is if the consumer is to use them to produce the user to take more responsibility after infection, according to the relevant law, the hospital will also undertake certain responsibility and punishment.Faced with such a situation, most hospitals have started to implement multi-layer depiction to prevent AIs. The first line of defense against infection in surgical operations is the aseptic shielding system, which is a key link to prevent cross infection between HAIS and surgical operations.With the improvement of people's awareness of methods and attention to germs, more reasonable medical and health care procedures have been produced, thus leading to an increase in the demand for medical non-woven fabrics.Meanwhile, in order to reduce their own risks, the manufacturers of medical protection products have to strengthen the safety testing of their products.
The safety of surgical non-woven fabrics, such as surgical sheets, operating clothes and operating kits, in close contact with the human body is first manifested as biocompatibility.According to the interpretation of IS0 meeting, biocompatibility refers to a performance of the reaction of living tissue to non-active materials, which generally refers to the compatibility of the material with the host, namely whether the material will cause toxicity to human tissues after contact with the human body. Biocompatibility includes histocompatibility and blood compatibility.
Biocompatibility evaluation on the current medical non-woven main reference 1 s010993 and GB/T16886 "biological evaluation of medical regarding machinery" series standard, according to its classification standard, as a gown, surgical drapes and kits and other medical non-woven fabric as part of the surface contact, so need a biocompatibility test including three cell toxicity, stimulation, sensitization.
(1) Cytotoxicity test: extract of the material itself and/or the material can be used (select a certain extraction medium, in simulation or strict condition of clinical use of leaching leaching) under the condition of experiment, using the selected cell lines and culture medium preparation test required enough new cell, to adopt at least three parallel test sample number and control number, respectively to extract test, direct contact with the test, the indirect contact test or membrane diffusion test, test of cultured cells were examined with a show mirror before nearly converge and form.
Can adopt the method of quantitative or qualitative detection detection cytotoxicity: qualitative evaluation cells were examined with a microscope (if needed, use cytochemistry staining), evaluation, such as general form, vacuolization, fall off, and the appearance of the cells, and the change of the respect such as membrane integrity, generally in the form of change can be descriptive bearing in a test report or in digital records, to the meaning of test materials scoring as shown in table 1.Quantitative evaluation can be used to determine cell death, cell growth inhibition, cell reproduction or cell cloning formation. Objective methods can be used to quantify the number of cells, total protein, enzyme release, in vivo dye release and reduction or other measurable parameters.
(2) Skin irritation test: animal skin irritation test and human skin irritation test are included. Animal skin irritation test is usually preferred In other words, relevant animal models were adopted to evaluate the potential of the material to produce skin irritation response under experimental conditions, and rabbits were the preferred test animals.After removing the hair on both sides of the animal's back and spine, observe the skin reaction of the sample or its extract after contacting with the animal's skin for a certain period of time, score and calculate the accumulative stimulation index.
(3) Sensitization test: The most commonly used test methods for delayed type hypersensitivity reaction are the maximum dose test and closed application test of guinea pigs.For medical non-woven fabrics, its application is in direct contact with the human body, so it is suitable for closed adhesive test, that is, to evaluate the potential of the material to produce guinea pig skin sensitization reaction under test conditions.
The results were evaluated as follows :1. The level of animals in the control group was less than 1, while that of the experimental group was greater than or equal to 1 generally indicated sensitization; 2.2.When the level of animals in the control group was greater than or equal to 1, the reaction of animals in the test group exceeded the most severe reaction in the control group and was considered sensitized.