Medical functional fiber materials
General
Many scientists are devoted to the exploration of the mystery of life, mainly focusing on: the structure of biological tissue; The relationship between structure and organ function; Design and development of biological organs.
Requirements for medical materials: first of all, it must have medical function, but also must emphasize safety. For external medical materials, the contact time with the body is short, and the requirements are slightly lower, while for materials directly in contact with blood or implanted in the body, the requirements are higher, that is, good biocompatibility. All medical materials shall meet the following basic requirements:
(1) The purity of polymer is high;
(2) The chemical property is not active;
(3) Non toxic, no tumor or allergic reaction, no foreign body reaction;
(4) Stable physical and chemical properties and good mechanical properties;
(5) Excellent biocompatibility;
(6) Can withstand the necessary disinfection treatment;
(7) It is easy to process into necessary complex shape.
Medical soft tissue materials
Super absorbent fiber materials
Superabsorbent material is a kind of polymer material with strong water absorbing group and certain crosslinking degree. Water absorption capacity up to
500-2500 times of its own weight, even up to 5000 times.
Type: starch, cellulose, polyacrylic acid, polyacrylonitrile hydrolysate, vinyl acetate copolymer, modified polyvinyl alcohol.
Medical suture
Non absorbent: silk, silver, polyamide, polyethylene, polyester, etc.
Absorption: bone collagen, catgut, chitin, polyglycolic acid, glycolide lactide copolymer, polyethylene glycol acid terpolymer, etc.
● radioactive fibers.
Edible health fiber
Artificial skin
Function: prevent the evaporation or loss of water and body fluid; Prevention of bacterial infection; send
Granulation or epithelial growth; Promote wound healing.
Requirements: soft, good elasticity, close to the wound; Moisture permeability, air permeability and resistance
Bacteria; No stimulation; It can promote the growth of new skin; It can be sterilized.
Artificial blood vessel
Medical oxygen enricher: enriches oxygen in the air to 40% or more.
Nerve channel
Fruit preservation system: make the surrounding atmosphere contain 23% O, 25% CO and 92% N2.
Antibacterial and deodorizing fiber
Anesthetic fibers
Artificial organs
Artificial kidney hemodialyzer
Due to renal organic lesions, accidents, poisoning and other reasons, renal failure causes metabolic substances to deposit in the body, resulting in uremia. Artificial kidney mainly uses dialysis function to replace renal function to remove metabolic wastes in human body, such as urea, uric acid and creatinine. There are three types of artificial kidney: hemodialysis, hemofiltration and hemodiafiltration. Among them, hemodialyzer is the most widely used. The flow diagram of artificial kidney dialyzer is as follows
Artificial liver dialyzer
The liver is an important organ with multiple functions, and it is also the main organ in the human body to remove toxins. Liver can be damaged by poisoning caused by overdose, allergy, acute hepatitis and other reasons, thus losing the detoxification function. The increase of the concentration of harmful substances in the blood can cause neurological symptoms, drowsiness, and eventually lead to death.
Artificial liver mainly uses adsorption method and dialysis method. The former has many shortcomings, so it has been abandoned. Dialysis methods are developing.
Ultrafiltration concentrator for liver ascites
Ascites is a common disease. In clinical practice, ascites in the body of the patient is usually removed regularly to alleviate the disease, but at the same time, protein must be reinfused to the patient.
Ascites concentrator is a new technology to concentrate ascites in patients' body, remove water and useless substances to human body, and transfer the protein back to patients. Sometimes, liver cirrhosis and liver cancer occur simultaneously. Before ascites concentration, cancer cells and bacteria should be removed first, and then water and low molecular waste liquid should be removed.
Blood concentrator
Hemodilution is widely used in open heart surgery with cardiopulmonary bypass to reduce blood cell damage and peripheral resistance. Hemodilution can cause organ edema, increase extracellular fluid, and affect the recovery of cardiopulmonary function. Using blood concentrator to remove excess water is the main method currently used.
Artificial lung
Artificial lung is mainly used in thoracic surgery and adjuvant treatment of dyspnea. The original air bubble artificial lung has been replaced by membrane artificial lung.
Mixed artificial organs
The development of artificial organs has gradually entered the mixed type, that is, from single function to multi-function. For example, enzyme and biological cells are fixed on polymer materials to make bioactive artificial organs.
When the protease is fixed on the outer side of the membrane of the artificial liver, the albumin can enter the blood through the membrane.
When urease, glutamate dehydrogenase and glucose dehydrogenase are fixed in the artificial kidney, the metabolite urea in the blood is transformed into ammonia under the catalysis of enzyme, and then into glutamate under the catalysis of enzyme, which makes the hybrid artificial kidney have higher functions.
Polymer drugs and drug fibers
Polymer drugs
Traditional low-molecular-weight drugs lack persistence because they are easy to be absorbed and excreted; Drugs are widely distributed in the body and lack of selectivity.
The polymer drugs developed in recent years can basically overcome the above shortcomings. At present, the main research directions are: drug controlled release; Sustained drug release; Drugs were mainly concentrated in specific sites (lesions).
Type: polymer with drug activity; Polymer carrier drugs; Low molecular weight drugs are embedded in polymer membranes. Release and delivery system of polymer substances: after polymer drugs enter the body, they are directed and gathered to the diseased organs, organs or cells with appropriate concentration, duration, so as to give full play to the efficacy of drugs.
The release system of polymer drugs can be divided into three parts
(1) Time controlled release system: zero level release; Pulse release
(2) Position control delivery system
(3) Intelligent drug delivery system: the drug is released at a given place, time and dose.
Drug fiber
Textile as a drug carrier has a long history. For example, from the ancient sachet, sachet developed from the sleeping pillow, Shengong Yuanqi bag and other health care products; Another example is Shangshi Zhitong ointment, Shixiang nuanchuan ointment and so on.
Drug fibers mainly use fibers with the largest surface area, which is conducive to drug release; Textile is most closely related to human life, and the fabric with drug function will provide great convenience for the treatment of diseases.
Types of drug fibers:
(1) Wound covering type: hemostatic fiber, anesthetic fiber, etc. The drug fiber can be processed into non-woven fabric or directly covered on the wound or surgical wound.
(2) Skin absorption type: such as antipruritic, contraception, anti-inflammatory and analgesic, anti heart disease and other fiber.
(3) Oral type: such as gastric drug fiber. The carrier fiber can be bioabsorbable or nonabsorbable.
(4) In vivo implantation: such as drug suture, etc.
Advantages of drug fiber:
(1) The effectiveness and safety of the drug were improved.
(2) It can improve the drug persistence and avoid the tedious of frequent medication.
(3) The comfort and convenience of medication were improved
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