小洵的微生物笔记4
第四章杀菌灭菌,一二三章后补...
也不叫笔记了,纯粹就是把老师PPT翻译了一下
4 Sterilizationand Disinfection(杀菌消毒)
4.1 Basicterms of sterilization and disinfection 杀菌消毒的专业术语
4.1.1.Sterilization(灭菌)
- Aphysical or chemical process that completely destroys all microbial life,including spores.
- Sterilization results in absolute absence of all viable microorganisms, including vegetativeforms and spores.
只要进入人体内部包括进入血液、组织、体腔的医用器材,如手术器械、注射用具、一切置入体腔的引流管等,都要求绝对无菌。在实验室、培养基和相关的试剂、器材也需要灭菌。
4.1.2Disinfection(消毒)
- Disinfectionis done to eliminate as many pathogenic microorganisms from an item or from theenvironment as possible, but not so sure to eliminate nonpathogenicmicroorganisms and spores.
- Disinfectants(消毒剂):Disinfectants can besporostatic but are not necessarily sporicidal.
4.1.3 Antisepsis(防腐)
- Use of chemical agents on skin orother living tissues to inhibit or arrest the growth and multiplication ofmicrobes.
- Bacteria normally don't die, buttheir growth are inhibited.
- Antiseptic(防腐剂)
通过去除尘埃和一切污秽以减少微生物数量的过程
4.1.5 Asepsis(无菌)
- Thereare no living microorganisms exist, mostly resulted from sterilization.
- Asepticoperation (无菌操作)refer to the operatingtechniques which prevent microbes from entering human bodies or other items.
4.2 Physical sterilization and disinfection 物理杀菌与灭菌
- Heat(热力)
- Radiation(辐射)
- Filtration(滤过)
- Lowtemperature and desiccation(低温和干燥)
湿热灭菌比干热灭菌的效力要好。
- Inmoist, bacterial proteins are more easily to coagulate and denature.
- Penetrating power of moist heat is stronger than dry heat.
- Steam has latent heat which can be released when gas transfer to liquid state andraise temperature rapidly
- Steam provides a means for distributing heat to all parts of sterilizing vessel.
- 干热灭菌:
- Incineration(焚烧)
- Cauterization(灼烧)
- Hotair drying sterilization(干烤)
- Infrared(红外线)
- Pasteurization(巴氏消毒法)
- Boilingmethod(煮沸法)
- Flowingsteam disinfection(流动蒸汽消毒法)
- Fractionalsterilization(间歇蒸汽灭菌法)
- Sterilizationby pressured steam(压力蒸汽灭菌法)
- Characters:simple, fast, thorough
- Used for: Contaminated wastes, pathologic specimens, dressings and paper withpurulent secretions, patients’corpses
- Method:directly burn or burn in incinerator
4.2.1.2 Cauterization(烧灼)
4.2.1.3 Hotair drying (干烤)
- Hotair sterilization/Baking(干烤)
- 171℃, 1h
- 160℃, 2h
- 121℃, 16h
- Make use of the specially made hot air drying oven to sterilize, the heat powerspread and penetration depends on the air convection and medium conduction, andthe effect of this method is reliable.
- Suitable for high temperature resistant articles(适合耐高温的物质)
- The articles that do not change incharacter, do not be damaged and do not evaporate at high temperature: oil,powder, glass products and metal products, etc.
- Not suitable for :Fiber products, plastic products
4.2.1.4 Infrared(红外线)
4.2.1.5 Pasteurization(巴氏消毒法)
- The act or process of heating a beverage or other food, such as milk or beer, to aspecific temperature for a specific period of time in order to killmicroorganisms that could cause disease, spoilage, or undesired fermentation
- 61.1~62.8℃for 30min or 71.7℃ for 15~30s(方法有两种)
- This temperature dose not sterilize the food, but sufficiently kill most of thevegetative cells.
- It is widely used in disinfecting milk, wine, and beer, etc.
4.2.1.6 Boilingmethod(煮沸法)
- One of the earliest used methods of disinfection.
- Brush and clean the articles, drip them into the water thoroughly, then heat and boilthe water.
- Timing starts from the boiling , if anything added during the boiling, timing starts from the second boiling.
- Suitable for articles which are moist-stable and temperature proof : metals, china, andglass, etc.
- The temperature of boiling water is 100℃. Normally vegetative cells will be killedin 5min, but spores need 1-2h to be killed.
- Mix sodium bicarbonate (小苏打) into water to make the concentration 1%~2% , which can cause theboiling point to be 105 ℃.
此法常用于消毒食具、刀剪、注射器。
4.2.1.7 Flowing steam disinfection(流动蒸汽消毒法)
- Arnold Sterilizer (Arnold消毒器)
- It applies water vapor to disinfect 100 ℃ (1 atm) for 15-30min .
- Vegetative bacteria can be killed, but not spores.
- Chinese steamers and some feeding bottle sterilizers have the same principles.
4.2.1.8 Fractional sterilization(间歇蒸汽灭菌法)
- It takes water vapor intermittently to sterilize at common pressure.
- Commonly used for sterilizing the medium containing sugar or milk which can not bearhigh temperature.
- Steam heating (100℃, 30 min) à37℃ overnight for endospores to germinate à 100℃, 30 min to kill germinatedendospores à 37℃ overnight for remainingendospores to germinate à 100℃, 60 min to kill last remaininggerminated endospores
- 蒸汽加热(100℃, 30 min) à37℃ 过夜使芽孢萌发à 100℃, 30 min 来杀死萌发的芽孢 à 37℃ 过夜使剩余的芽孢萌发à 100℃, 60 min 来杀死剩余的芽孢
- The most effective sterilizing method
- Autoclaving: When pressure is 103.4kPa, the temperature in the autoclave can reach 121.3℃,15-20min is enough for sterilization
- Kill both vegetative organisms and endospores
- Commonly used for the articles which are heat-stable, pressure-proof, and can bear damp:ordinary medium, normal saline, surgical dressing, etc
但上述温度还不能灭活朊粒。
4.2.2 Radiationdisinfection(辐射杀菌法)
- Ultraviolet ray (UV)(紫外线)
- Ionization radialization(电离辐射)
- Microwave disinfection(微波)
- Wavelength: 240~300nm, the most effective: 265~266nm
- Mechanism:blockage of DNA replication by forming thymidine dimmers
- Verypoor penetrating power
- Ultravioletrays can kill bacteria, viruses, fungi
- Causingeye damage, burns and mutation in skin cells
4.2.2.2 Microwavedisinfection(微波)
- Electromagneticwave (1-1000mm)
- Usedto sterilize food, metalloid instrument, etc
4.2.3 Filtration(滤过除菌法)
- Sterilizesolutions that may be damaged or denatured by high temperatures or chemicalagents.
用于一些不耐高温或容易被化学物质破环的血清、毒素、抗生素的除菌。
4.2.4 LowTemperature(低温)
- -20℃~ -70℃
- Inhibitsmicrobial growth by slowing down microbial metabolism
- Usedto conserve bacterial strains
4.2.5 Desiccation(干燥)
- High concentrations of salt or sugar
- Microorganisms can not grow without water
- The high osmotic strength can damage cells by plasmolysis.
- Not effective against endospores
- Used to conserve food
4.2.6 Lyophilization(冷冻真空干燥法)
- Usedfor long-term reservation of bacteria stocks
- Fast freezing + drying
- Protecting agents (glycerol, serum)
4.3.1 Chemical Disinfection and Sterilization(化学消毒灭菌法)
- The chemicals used for disinfection are called as disinfectants.
- The effects of some disinfectants are strong enough to sterilize, thesedisinfectants are also called as sterilants(杀菌剂).
4.3.2 Mechanismsof Chemical disinfectants(化学消毒的机制)
- To facilitate bacterial protein dissolution or coagulation
- To interfere the enzyme system and its metabolism, destroy the radical mass ofprotein and nucleic acid
- To damage bacterial cell membrane
4.4 Application of Disinfection andSterilization(消毒灭菌应用)
4.4.1医疗器械物品的消毒灭菌
高危器械物品
需进入无菌组织
灭菌
中危器械物品
不进入无菌组织
接触黏膜
消毒
低危器械物品
只接触未损伤皮肤,
不进入无菌组织
不接触黏膜
一般用后清洗、消毒
快速周转的医疗器械
快速消毒灭菌
不能损伤器械
4.4.2 室内空气消毒灭菌
物理消毒法
- 紫外线照射(1.5W/m3,1h)最常用;
- 滤过除菌
- 过氧乙酸喷雾、熏蒸
- 过氧化氢喷雾
- 二氧化氯溶液喷洒
- 中草药点燃烟熏
- 手和皮肤的消毒
- 用肥皂和流动水经常并正确洗手
- 病原微生物污染时应用消毒剂消毒。
- 3%H2O2:口腔粘膜消毒
- 0.01%-0.1%洗必泰或高锰酸钾:冲洗尿道、阴道、膀胱等
- 1%硝酸银:新生儿滴眼以预防淋球菌感染。
- 用等量的200g/L漂白粉搅拌均匀作用2h
- 日常生活小用具:0.5%过氧乙酸浸泡
- 家具: 0.5%过氧乙酸擦洗
- 衣服、被褥:流动蒸气消毒30min
- 自来水:氯气消毒;少量饮用水:漂白粉
- 厕所、阴沟:生石灰(氢氧化钙)
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