Kovács Ottó Miklós Polymers in medicine.Lecture: Central European University. / Curing Department / Tihung Plastic Factory ChinaProducts used in the medical field, adequately separated, Class 8 in sterile manufacturethe high expectations of customers and DIN EN ISO 13485:2007 standard. The sterilearea of production includes the 250-500 CN closing force between the molding and thethree-shift assembly.The advantages of using plastics in health care(Eg chemical resistance, heat resistance-tion, strength, workability).The biocompatible materials:In particular, the best prospects of a technical plastics are as polycarbonate,thermoplastic elasztome agents, silicones, polysulfones. In applications requiringbiocompatibility it is worth mentioning the catheters, intravenous (IV) sets, blood-storagedevices or orthopedic implants. The biocompatible PVC, PC demand is expected to be
high. The implants are shown also in the field of new materials, eg. polycarbonate orPEEK [poly (ether ether ketone]. polymers as implants made which are suitable for 30days longer than contact with blood, bones, fabrics. are short, or even continuouscarbon fiber versions, the latter especially in metal replacementare suitable. The types of biocompatible Makrolon impact resistance, their transparencyand durability, makes it attractive for sterilization. PC.ABS are flame retardant types,which are operating in a sterile environment for the manufacture of devices can be usedto cover, because the treatment is well tolerated and chemical disinfectants.The latextartal-containing PVC and rubber parts replacement for, due to their lowerallergy risk to the patient. Micro injection molded products: screw diameter 12 mmPA / imide / thousands of parts / min velocity, ie low-friction, wear-resistant materialsneeded. The high strength, the material has very good heat resistance (260 ° C) andvery low creep to hajlama.POM LCP, PA12 / lauryl and lactate / types of high quality anddimensional accuracy in catheters process - both harder and elastomer-modified form.The catheters are made of chemical resistant, compatible with tissues and non-toxic,meet the European and the U.S.health requirements are the most usual method ofsterilization sterilization. These polymers are mainly known. dilatation catheters used inthe production, in which the mechanical properties are very important: a well must beintroduced, not bend, do not break it apart and repedhetnek.PBT also come into contact with many types of materials can be well processed andaccurate, Lake mérettar products made from them. Low friction allows tooldimensionalhouse, and pipettes inhelt system or prepare them. However, suitable for fiber drawingfilter media making.variable thermal method, which is used successfully in the dynamictempering and other micro-injection molding techniques. The method is that the surfaceof the tool plastic injection before the melt is heated to a temperature without mould wallthroughout this temperature.It is very important to strictly comply with the processing parameters. The tool normallybe evacuated, and to prevent the mold halves between the accumulation of staticelectricity.The so-called. montage to use during the injection molding, the injection molding ofplastics that some do not stick to each other and thus moving parts are molded in asingle step. In the post-installation steps are avoided. Today, this process will also beavailable in micro, thus for example. Complete gear systems is also a mold can bepoured. Small motors, micro-pumps can be used mikrofluidikában prepared by thistechnique.
The sterilization procedures for the processes of patient care as a whole, during which avariety of materials and tools sterile, or sterilized makethat can be used in medical facilities and small praxisokban. The most common methodsof sterilization steam, hot air, gas, and plasma sterilization. The sterilized products mayinclude, inter alia, to be supplied non-sterile or repeatedly use metal tools andinstruments, textiles, surgical dressings and sutures, as well as rubber, plastic, glasstools, utensils, equipment or parts in contact with patients. These sterilizers csírátlanítjákafter proper preparation, properly stored until use.Cleaning and disinfection of materials, equipment needs to be prepared for sterilization.The treatments and interventions have been used in place of the use of the itemscontained collected, sorted, in several parts of dismantled equipment. Subsequently, theimpurities (e.g., blood, body fluid) of chemical and mechanical methods,manually ormechanically removed. After cleaning, disinfection occurs, during which the aim is thatthe steriliser materials, pre-sterilization of the seed number as low as possible, thusimproving the process efficiency, the prevention of infection. This is new, but the factorynon-sterile products should be exercised in the same way as if they had been used, oroccasionally cleaning and disinfection must always advance.PackingPrepared for sterilization trayThe products are cleaned and disinfected after individually or grouped according to thepurpose of use, packaged. To do this, special packaging materialsor boxes are available. The different processes have different properties packingmaterials are used, which are kept for some time after the sterilizationthe product is sterile. These presentations can be in terms of their rolls, pouches,packaging materials arched or traditional textiles. The sterilization indicator, preparedpackages supplied with which to check the effectiveness of sterilization..
SterilizeThe proper functioning of sterilizers trade official conditions and regulations should betested. The technical review, biological indicators are also used for this purpose.Chemical indicators on a daily basis,by running test programs and data recorders built into machines to be satisfied onlyprovided for the sterilization cycle parameters have been met.Steam sterilization (autoclaving)The procedure is that the working space of the autoclave, so the packets are placedinside vacuuming was evacuated and then pressurized, the air is saturated with watervapor is injected into place. The water vapor condenses on the packages, as well as inthemeans, while releasing heat, which causes the microorganisms are killed. This time, themachine can be the pressure lifted, the load is dried, cooled. This is a sterilization cycle.Steam sterilization machine, depending on the parameters:121 ° C for 15-20 minutes,134 ° C for 3-10 min can be.Autoclavable materials: metal, surgical instruments, surgical textiles, bandages, rubberand autoclavable plastic products, glass and porcelain. Packaging material used: As thesteam must penetrate the packaging,and the entire surface of the equipment to be incontact, therefore, only suitable permeable packaging material used. In this specialpaper, plastic combination, surgical towel, non-woven fabric and so-called first-aid kit.The heat sterilizers located, packed devicesThe heat sterilization of the closed working chamber, electrically ensure the hot dry air,
which is then circulated through a fan. The hot air heats to the set temperature of theinserted devices. The specific time and temperature can be destroyed by micro-organisms. At the end of the cycle, the load is lowered.The hőlégsterilizálás parameters:160 ° C for 45 minutes,180 ° C for 25 minutes;200 ° C for 10 minutes.High-temperature sterilization equipment: metal, glass and packaging materialsporcelántermékek.Felhasználható: In this method, the packaging material requirementsto be met for an air-tight, heat resistance and good thermal conductivitybe. Polyamide films such as heat-resistant hose, a closed metal box, heat-resistantglass container, a special aluminum foil.Ethylen-oxid SterilisationEthylene oxide gas sterilizationThe ethylene oxide sterilization, the deaerated working chamber the temperature andhumidity of the cargo előkondicionálják, and then injected into the space defined in aconcentration of ethylene oxide, which can be time destroys the microorganisms. Thecycle of the working chamber at the end of the ethylene oxide is removed and then thepackets to the appropriate time prior to use ventilated. The ethylene oxide sterilizationparameters:Gas concentration: 650-1200 mg / lRelative humidity: 70-90%Temperature: 37-55 ° CTime: 2-6 hours, depending on the previous parameter.Ethylene oxide sterilization devices: synthetic sutures, reusable plastic and rubber,appliances. Packaging material: special paper-plastic bag or a combination of roll, whichwas developed for this purpose welding machines, closed down.Formaldehyde gas sterilizationAutoclave tests and formaldehyde gas sterilization indicators used in the workspacevented pressurized water vapor mixed with formalin injected. Of about 60-80 ° C. Thesolution is released into the working space of the formaldehyde gas, which kills orinactivates the microorganisms. Ethylene oxide is a less efficient, more sensitive tosterilization parameters changes, especially changes in temperature, and the materialitself is extremely irritating.
The formaldehyde sterilization parameters:gas concentrations: 0.2-1.5 g / lTemperature: 60-80 ° C, depending on machineRelative Humidity: 100% Exposure time: 30 minutes to 2 hours.Sterilized with formaldehyde materials: rubber and plastic can be used more than once,instruments and appliances. Packaging material: the ethylene oxide sterilization is used,paper-plastic bag or a combination of rolls, welding machines, closed down.Plasma sterilizationDuring the process, hydrogen peroxide is used csíramentesítésre plasma state. Thevented, low-temperature hydrogen peroxide is injected into the working area, a vaporinto contact with a sterilized, packaged devices. This After radio frequency energy usingelectric field is established in the working space, whereupon the hydrogen peroxideplasma state (the so-called Fourth of state). The plasma chemical substances (activefree radicals) to kill the microorganisms. During this process, the energy level isdecreased and the fresh plasma of hydrogen peroxide and water vapor, oxygen, andotherbyproducts. The air pressure in the working chamber, and the balance are immediatelyusable.The plazmasterilizálás parameters:Temperature: usually 46 ° CCycle time: 45 to 75 minutes depending on the machineplasma phase, 400 W and 13.56 MHz radio frequencyPlasma sterilization devices: the costs, the procedure is the most expensive, but it is thegentlest means, due to low temperatures. Thus, these sterilizers primarily sensitiveinstruments, micro surgical instruments, devices can be easily damaged piecescsírátlanítják.Packaging material: special polypropylene-based bags, hoses, sheet packing materialsand enclosures.Storage and shelf lifeThe tools used for packaging various times held sterilitásukat. This can range from 14days to 12 months, which may be extended wrapped. In any case, the point of usedevices and expand the time. Even at room temperature until used separately,should bestored in a dry and dust-free room.
You resorbable polymers for medical applicationsThe biodegradable polymers are used in medicine, mainly sebésztben. Like. Surgicalsaw wires transient adhesives, membranes, bone plates synthesis, pharmaceutical or ascarriers for controlled drug release systems. The biodegradable polymers optimalpharmaceutical use requires that their decomposition products taken feltudja biologicalcycle.The degradation of polymers made by different mechanisms:First Radiation or thermal decomposition when they break the covalent bonds to.SecondHydrolysis of the ester and amide group-containing-polymers occurs.Third Enzymaticeffect. This mainly occurs in the natural polymers, eg. chitin, alginate, silk, keratin,collagen. Etc.