{"id":15440,"date":"2019-11-22T11:43:11","date_gmt":"2019-11-22T10:43:11","guid":{"rendered":"https:\/\/www.rct-online.de\/magazin\/?p=15440"},"modified":"2025-12-12T16:41:37","modified_gmt":"2025-12-12T15:41:37","slug":"sterilization-methods-and-aseptic-practice","status":"publish","type":"post","link":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/","title":{"rendered":"Sterilization Methods and Aseptic Practice"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_73 ez-toc-wrap-center counter-hierarchy ez-toc-counter ez-toc-white ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#What_Does_Sterile_Mean\" title=\"What Does Sterile Mean?\">What Does Sterile Mean?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Sterile_Work_in_Medicine_and_Research\" title=\"Sterile Work in Medicine and Research\">Sterile Work in Medicine and Research<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Various_Sterilization_Methods_for_Practical_Use\" title=\"Various Sterilization Methods for Practical Use\">Various Sterilization Methods for Practical Use<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Thermal_Sterilization_Methods\" title=\"Thermal Sterilization Methods\">Thermal Sterilization Methods<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Hot_Air_Sterilization\" title=\"Hot Air Sterilization\">Hot Air Sterilization<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Autoclaving\" title=\"Autoclaving\">Autoclaving<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Tyndallization\" title=\"Tyndallization\">Tyndallization<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#UV_and_Gamma_Irradiation\" title=\"UV and Gamma Irradiation\">UV and Gamma Irradiation<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Sterile_Filtration\" title=\"Sterile Filtration\">Sterile Filtration<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Chemical_Sterilization_Methods\" title=\"Chemical Sterilization Methods\">Chemical Sterilization Methods<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#Sterilization_Methods_in_Everyday_Laboratory_Practice\" title=\"Sterilization Methods in Everyday Laboratory Practice\">Sterilization Methods in Everyday Laboratory Practice<\/a><\/li><\/ul><\/nav><\/div>\n<p style=\"text-align: justify;\"><strong>In 2011, people became ill, and some even died as a result of an EHEC outbreak\u2014an intestinal infection caused by the enterohemorrhagic <em>Escherichia coli<\/em> bacterium. The cause was fenugreek sprouts contaminated with these pathogens, which were consumed as vitamin-rich raw food. This extreme case highlights the importance of sterility in food products. In even more sensitive environments, such as hospitals, sterility is crucial to prevent hospital-acquired infections caused by pathogen transmission.<\/strong><\/p>\n<h2><span class=\"ez-toc-section\" id=\"What_Does_Sterile_Mean\"><\/span>What Does Sterile Mean?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">Sterilization aims to kill virtually all microorganisms and pathogens present in a solution, on solid surfaces, or in the surrounding air. These include bacteria, viruses, and spores, as well as infectious proteins such as prions, and plasmids and other pathogenic DNA fragments.<\/p>\n<p style=\"text-align: justify;\">However, achieving 100% elimination of all microorganisms and pathogens is not possible in practice. Therefore, the success of a sterilization method is defined as the probability of reducing the number of viable microorganisms and pathogens below a threshold value. This is typically measured by the number of &#8220;colony-forming units&#8221; (CFU) still detectable after sterilization\u2014the remaining number of viable microorganisms.<\/p>\n<p><center><a href=\"https:\/\/www.rct-online.de\/en\/laboratory-equipment\/laboratory-instruments\/scoops-spoons-spatulas-and-tweezers\/29901\/knife-and-fork-for-sample-handling-sterile\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-4280 size-full\" title=\"Knife and Fork for Sample Handling - sterile\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/messer-und-gabel-zur-probenhandhabung-steril.jpg\" alt=\"Knife and Fork for Sample Handling - sterile\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/messer-und-gabel-zur-probenhandhabung-steril.jpg 300w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/messer-und-gabel-zur-probenhandhabung-steril-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a> <a href=\"https:\/\/www.rct-online.de\/en\/laboratory-equipment\/laboratory-instruments\/scoops-spoons-spatulas-and-tweezers\/29899\/sample-spoon-sterile\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-4281 size-full\" title=\"Sample Spoon - sterile\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/probenloeffel-steril.jpg\" alt=\"Sample Spoon - sterile\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/probenloeffel-steril.jpg 300w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/probenloeffel-steril-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/center><\/p>\n<p style=\"text-align: justify;\">A material treated by a specific sterilization method is considered &#8220;sterile&#8221; when a reduction in germ count by at least a factor of 10<sup>6<\/sup> has been achieved. In practical terms, this means that, out of one million identically treated units, colony-forming units (CFUs)\u2014i.e. viable germs\u2014may only be detectable in one unit.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Sterile_Work_in_Medicine_and_Research\"><\/span>Sterile Work in Medicine and Research<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">In the production of medications or injection solutions, sterility must be maintained throughout the entire process. Similarly, in hospitals, it is essential to ensure that not only medications but also medical devices and instruments that come into contact with patients are sterile, to prevent pathogen transmission.<\/p>\n<figure id=\"attachment_4264\" aria-describedby=\"caption-attachment-4264\" style=\"width: 600px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-4264 size-full\" title=\"Device for sterile cleaning of medical instruments\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/Geraet-zur-sterilen-Reinigung-von-medizinischen-Instrumenten.jpg\" alt=\"Device for sterile cleaning of medical instruments\" width=\"600\" height=\"400\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/Geraet-zur-sterilen-Reinigung-von-medizinischen-Instrumenten.jpg 600w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/Geraet-zur-sterilen-Reinigung-von-medizinischen-Instrumenten-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption id=\"caption-attachment-4264\" class=\"wp-caption-text\"><center>Device for sterile cleaning of medical instruments | \u00a9 EdNurg \u2013 stock.adobe.com<\/center><\/figcaption><\/figure>\n<p style=\"text-align: justify;\">In medical, biological, and pharmaceutical research as well, constant sterility is a prerequisite for safe, error-free work and thus for correctly interpretable results. For example, if a bacterial culture is contaminated by foreign organisms, misinterpretation of results is inevitable.<\/p>\n<blockquote>\n<p style=\"text-align: justify;\">To ensure sterile work under various conditions, different sterilization methods suitable for the respective material to be sterilized are available.<\/p>\n<\/blockquote>\n<p style=\"text-align: justify;\">For instance, a heat-sensitive culture medium, such as that required for enrichment cultures to detect microorganisms, must be treated differently than a surgical instrument made of stainless steel, titanium, or tantalum.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Various_Sterilization_Methods_for_Practical_Use\"><\/span>Various Sterilization Methods for Practical Use<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">Sterilization methods are generally classified by their fundamental mode of action into physical and chemical methods. Physical methods include thermal sterilization, sterile filtration, and irradiation using UV or gamma radiation. Chemical methods include fumigation with ethylene oxide or formaldehyde.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Thermal_Sterilization_Methods\"><\/span>Thermal Sterilization Methods<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">Thermal sterilization methods are divided into hot air sterilization and steam sterilization, also known as autoclaving. Both methods utilize the germicidal effect of heat.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Hot_Air_Sterilization\"><\/span>Hot Air Sterilization<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">Hot air sterilization is performed in sterilization ovens using dry heat. The material is typically exposed to +180 \u00b0C for two hours. This method is particularly suitable for glass, metal, or porcelain equipment that can easily withstand such high temperatures.<\/p>\n<figure id=\"attachment_4260\" aria-describedby=\"caption-attachment-4260\" style=\"width: 600px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-4260 size-full\" title=\"Modern autoclave for laboratory use\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/Moderner-Autoklav-fuer-den-Laborbereich.jpg\" alt=\"Modern autoclave for laboratory use\" width=\"600\" height=\"557\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/Moderner-Autoklav-fuer-den-Laborbereich.jpg 600w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/Moderner-Autoklav-fuer-den-Laborbereich-300x279.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption id=\"caption-attachment-4260\" class=\"wp-caption-text\"><center>Modern autoclave for laboratory use | \u00a9 HelenaW \u2013 commons.wikimedia.org<\/center><\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"Autoclaving\"><\/span>Autoclaving<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">For nutrient solutions used to cultivate microorganisms and for plastic materials such as <a href=\"https:\/\/www.rct-online.de\/en\/laboratory-equipment\/metering-facilities-and-metering-devices\/pipette-and-accessories\">pipettes<\/a>, <a href=\"https:\/\/www.rct-online.de\/en\/filtration\/syringes\">syringes<\/a>, or <a href=\"https:\/\/www.rct-online.de\/en\/laboratory-equipment\/laboratory-containers\/bottles-carboys-and-accessories\">laboratory bottles<\/a>, steam sterilization in an autoclave is the method of choice.<\/p>\n<p style=\"text-align: justify;\">The operation of such sterilizers is comparable to that of a pressure cooker: in a sealed vessel equipped with a pressure relief valve, water is heated to +121 \u00b0C, generating a steam pressure of approximately 2 bar, and the steam displaces the air through the valve. The material to be sterilized is &#8220;autoclaved&#8221; under these conditions for a specified time, typically 20 minutes. This causes proteins and nucleic acids to denature, leading to the death of microorganisms and thus to sterilization.<\/p>\n<p style=\"text-align: justify;\">Autoclaving is particularly effective for killing spores, especially bacterial endospores, because the moist air causes the resistant cell walls of the spores to swell, thereby reducing their thermal resistance. Spores are far less sensitive to dry heat.<\/p>\n<p><center><a href=\"https:\/\/www.rct-online.de\/en\/tube-hose-connectors\/connectors-made-of-plastic\/luer-lock-connectors\/28848\/luer-lock-tubing-adapter-female-for-flexible-tubing\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-4285 size-full\" title=\"Luer-Lock Tubing Adapter (Female) for Flexible Tubing\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/luer-lock-schlauchadapter-weiblich-fuer-weiche-schlaeuche.jpg\" alt=\"Luer-Lock Tubing Adapter (Female) for Flexible Tubing\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/luer-lock-schlauchadapter-weiblich-fuer-weiche-schlaeuche.jpg 300w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/luer-lock-schlauchadapter-weiblich-fuer-weiche-schlaeuche-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a> <a href=\"https:\/\/www.rct-online.de\/en\/tubes-hoses\/tubing-made-of-elastomers-soft-rubber\/silicone-tubing\/28690\/silicone-tubing-for-medical-engineering-platinum-vulcanized\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-4286 size-full\" title=\"Silicone Tubing for Medical Engineering - platinum-vulcanized\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/silikonschlauch-fuer-die-medizintechnik-platinvernetzt.jpg\" alt=\"Silicone Tubing for Medical Engineering - platinum-vulcanized\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/silikonschlauch-fuer-die-medizintechnik-platinvernetzt.jpg 300w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/silikonschlauch-fuer-die-medizintechnik-platinvernetzt-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/center><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Tyndallization\"><\/span>Tyndallization<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">Tyndallization is a &#8220;fractional&#8221; sterilization method in which the material to be sterilized is heated to +100 \u00b0C several times and then incubated at approximately +30 \u00b0C for extended periods. The purpose of this procedure is to allow the dormant forms of microorganisms\u2014the spores\u2014to germinate between the heating steps. In this state, they lose their heat resistance and are killed during the subsequent reheating.<\/p>\n<p style=\"text-align: justify;\">A significant disadvantage of this gentle method, which dates back to the Irish polymath John Tyndall (1820\u20131893), is the considerable time required. It is therefore no longer relevant for laboratory use but still has applications in the food industry.<\/p>\n<figure id=\"attachment_4256\" aria-describedby=\"caption-attachment-4256\" style=\"width: 414px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-4256 size-full\" title=\"The Irish physicist John Tyndall (1820\u20131893)\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/John-Tyndall.jpg\" alt=\"The Irish physicist John Tyndall (1820\u20131893)\" width=\"414\" height=\"550\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/John-Tyndall.jpg 414w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/John-Tyndall-226x300.jpg 226w\" sizes=\"(max-width: 414px) 100vw, 414px\" \/><figcaption id=\"caption-attachment-4256\" class=\"wp-caption-text\"><center>The Irish physicist John Tyndall (1820\u20131893) | \u00a9 Tucker Collection \u2013 commons.wikimedia.org<\/center><\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"UV_and_Gamma_Irradiation\"><\/span>UV and Gamma Irradiation<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">Microorganisms and pathogens are killed by exposure to UV or gamma radiation through radiochemical mechanisms. UV light in the wavelength range between 200 and 300 nm is used particularly for operating microbiological safety cabinets. These workstations, also known as laminar flow cabinets, are enclosed work tables equipped with a special ventilation system that continuously supplies sterile air to the work area while preventing particles\u2014and thus germs\u2014from the surrounding air from entering the workspace.<\/p>\n<p style=\"text-align: justify;\">The antibacterial effectiveness of UV radiation on microorganisms and pathogens is based on energy absorption by DNA and RNA. The radiation causes irreversible chemical changes in these large biomolecules, damaging the microorganisms and pathogens and subsequently causing them to die.<\/p>\n<figure id=\"attachment_4258\" aria-describedby=\"caption-attachment-4258\" style=\"width: 600px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-4258 size-full\" title=\"UV sterilizer with surgical instruments\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/UV-Sterilisator-mit-chirurgischen-Instrumenten.jpg\" alt=\"UV sterilizer with surgical instruments\" width=\"600\" height=\"400\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/UV-Sterilisator-mit-chirurgischen-Instrumenten.jpg 600w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/UV-Sterilisator-mit-chirurgischen-Instrumenten-300x200.jpg 300w\" sizes=\"(max-width: 600px) 100vw, 600px\" \/><figcaption id=\"caption-attachment-4258\" class=\"wp-caption-text\"><center>UV sterilizer with surgical instruments | \u00a9 New Africa \u2013 stock.adobe.com<\/center><\/figcaption><\/figure>\n<p style=\"text-align: justify;\">Gamma irradiation also employs comparable radiochemical mechanisms that disable the functionality of microorganisms, viruses, and pathogens. Both irradiation facilities based on radionuclides such as cobalt-60 or cesium-137 and electronic radiation sources, including X-ray tubes, are used for this purpose. The latter offer greater radiation safety for operating personnel than continuously emitting radionuclide sources, as they can be switched off.<\/p>\n<blockquote>\n<p style=\"text-align: justify;\">X-ray and gamma irradiation offer the advantage over UV irradiation of being able to penetrate matter and therefore remain effective even in packaged materials. They are primarily used for industrial sterilization of final-packaged and palletized in-vitro diagnostics (IVD) and other medical products such as syringes, surgical supplies, or dressings, which can be used immediately after irradiation.<\/p>\n<\/blockquote>\n<p style=\"text-align: justify;\">Radioactive contamination of the treated material is completely impossible with X-ray and gamma radiation, as the material is merely exposed to higher-energy electromagnetic radiation that cannot cause changes to atomic nuclei and therefore cannot induce radioactive activation.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Sterile_Filtration\"><\/span>Sterile Filtration<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">Some solutions, such as vaccines and liquid culture media, are heat-sensitive and cannot be sterilized by conventional heat sterilization methods. Sterile filtration is suitable for these applications, as it does not thermally stress the material. The solution is passed through sterile <a href=\"https:\/\/www.rct-online.de\/en\/filtration\">filters<\/a>, usually membrane filters with a pore size of 0.2 \u00b5m, which microorganisms such as bacteria cannot pass through. Sterile filters are also used for decontaminating gases, for example when aerating sterile solutions or cultures.<\/p>\n<p><center><a href=\"https:\/\/www.rct-online.de\/en\/filtration\/prefilters-and-filter-holders\/30791\/in-line-filter-made-of-ptfe\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-4267 size-full\" title=\"In-Line Filter made of PTFE\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/in-line-filter-aus-ptfe.jpg\" alt=\"In-Line Filter made of PTFE\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/in-line-filter-aus-ptfe.jpg 300w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/in-line-filter-aus-ptfe-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a> <a href=\"https:\/\/www.rct-online.de\/en\/filtration\/prefilters-and-filter-holders\/30792\/high-chem-membrane-filter-made-of-ptfe\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-4268 size-full\" title=\"High-Chem Membrane Filter made of PTFE\" src=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/membranfilter-aus-ptfe.jpg\" alt=\"High-Chem Membrane Filter made of PTFE\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/membranfilter-aus-ptfe.jpg 300w, https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/membranfilter-aus-ptfe-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/center><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Chemical_Sterilization_Methods\"><\/span>Chemical Sterilization Methods<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">In addition to thermal methods, chemical sterilization methods are also used in practice, primarily for decontamination tasks in hospitals. For surfaces, such as hospital furniture or equipment, alcohols like isopropanol, as well as solutions of formaldehyde, peracetic acid, and phenols like m-cresol, are used. Their wetting ability is enhanced by the addition of detergents. Solutions of quaternary ammonium compounds, mainly used for household hygiene, also have germ-reducing effects. Microbicidal gases for textile disinfection, such as the treatment of hospital laundry, include ethylene oxide and formaldehyde gas, and less commonly chlorine gas, in appropriate dilutions.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Sterilization_Methods_in_Everyday_Laboratory_Practice\"><\/span>Sterilization Methods in Everyday Laboratory Practice<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p style=\"text-align: justify;\">The Robert Koch Institute (RKI) in Berlin, a central German federal institution whose primary tasks involve &#8220;the scientific investigation, epidemiological and medical analysis and assessment of diseases with high risk potential, high prevalence, or high public or health policy significance,&#8221; published an updated &#8220;List of Tested and Approved Disinfectants and Methods&#8221; in October 2017 (Bundesgesundheitsblatt 2017.60:1774-1297). These provide assurance of optimal results when used properly and professionally.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In 2011, people became ill, and some even died as a result of an EHEC outbreak\u2014an intestinal infection caused by the enterohemorrhagic Escherichia coli bacterium. The cause was fenugreek sprouts contaminated with these pathogens, which were consumed as vitamin-rich raw food. This extreme case highlights the importance of sterility in food products. In even more &hellip;<\/p>\n","protected":false},"author":7,"featured_media":12043,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,3028,2748],"tags":[3037,3038,3039,2775,3046],"class_list":["post-15440","post","type-post","status-publish","format-standard","has-post-thumbnail","","category-all-articles","category-alle-beitraege-en","category-materials-in-chemistry","tag-luer-lock-en","tag-medizin-en","tag-medizintechnik-en","tag-ptfe-en","tag-schlaeuche-en"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v23.1 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Sterilization Methods and Aseptic Practice - RCT Magazine<\/title>\n<meta name=\"description\" content=\"Sterilization in Laboratory &amp; Medical Settings \u2013 Autoclaving \u2714 Tyndallization \u2714 UV &amp; Gamma Irradiation \u2714 Sterile Filtration \u2714 Chemical Methods \u2714\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Sterilization Methods and Aseptic Practice - RCT Magazine\" \/>\n<meta property=\"og:description\" content=\"Sterilization in Laboratory &amp; Medical Settings \u2013 Autoclaving \u2714 Tyndallization \u2714 UV &amp; Gamma Irradiation \u2714 Sterile Filtration \u2714 Chemical Methods \u2714\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/\" \/>\n<meta property=\"og:site_name\" content=\"Reichelt Chemietechnik Magazine\" \/>\n<meta property=\"article:published_time\" content=\"2019-11-22T10:43:11+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2025-12-12T15:41:37+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"800\" \/>\n\t<meta property=\"og:image:height\" content=\"516\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Dr. Karl-Heinz Heise\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Dr. Karl-Heinz Heise\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"10 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/\",\"url\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/\",\"name\":\"Sterilization Methods and Aseptic Practice - RCT Magazine\",\"isPartOf\":{\"@id\":\"https:\/\/www.rct-online.de\/magazin\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg\",\"datePublished\":\"2019-11-22T10:43:11+00:00\",\"dateModified\":\"2025-12-12T15:41:37+00:00\",\"author\":{\"@id\":\"https:\/\/www.rct-online.de\/magazin\/#\/schema\/person\/de5369aedc25d1f064871d823629e056\"},\"description\":\"Sterilization in Laboratory & Medical Settings \u2013 Autoclaving \u2714 Tyndallization \u2714 UV & Gamma Irradiation \u2714 Sterile Filtration \u2714 Chemical Methods \u2714\",\"breadcrumb\":{\"@id\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#primaryimage\",\"url\":\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg\",\"contentUrl\":\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg\",\"width\":800,\"height\":516,\"caption\":\"\u00a9 romans14 \u2013 stock.adobe.com\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.rct-online.de\/magazin\/en\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Sterilization Methods and Aseptic Practice\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.rct-online.de\/magazin\/#website\",\"url\":\"https:\/\/www.rct-online.de\/magazin\/\",\"name\":\"Reichelt Chemietechnik Magazine\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.rct-online.de\/magazin\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.rct-online.de\/magazin\/#\/schema\/person\/de5369aedc25d1f064871d823629e056\",\"name\":\"Dr. Karl-Heinz Heise\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.rct-online.de\/magazin\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2024\/07\/KH_Heise.jpg\",\"contentUrl\":\"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2024\/07\/KH_Heise.jpg\",\"caption\":\"Dr. Karl-Heinz Heise\"},\"description\":\"Dr. Karl-Heinz Heise studierte an der Martin-Luther Universit\u00e4t Halle-Wittenberg Chemie und der vormaligen Technischen Hochschule Dresden Radiochemie und Chemische Kerntechnik. Danach war er bis zur politischen Wende 1989 als wissenschaftlicher Mitarbeiter am Zentralinstitut f\u00fcr Kernforschung Rossendorf (ZfK) der Akademie der Wissenschaften in verschiedenen Bereichen der Isotopenproduktion und Markierungschemie t\u00e4tig. 1990 wurde er im neu gegr\u00fcndeten Leibnitz-Forschungszentrum Dresden - Rossendorf, dem heutigen Helmholtz-Zentrum, mit der Leitung der Abteilung f\u00fcr Organische Tracerchemie des Instituts f\u00fcr Radiochemie betraut, die sich mit umweltchemischen Prozessen in den Hinterlassenschaften des Uranbergbaus der DDR befasste. Dr. Heise ist begeisterter Hobby-Numismatiker und besch\u00e4ftigt sich dabei vornehmlich mit der h\u00f6fischen Medaillenkunst des 19. Jahrhunderts in Sachsen.\",\"url\":\"https:\/\/www.rct-online.de\/magazin\/en\/author\/k-heise\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Sterilization Methods and Aseptic Practice - RCT Magazine","description":"Sterilization in Laboratory & Medical Settings \u2013 Autoclaving \u2714 Tyndallization \u2714 UV & Gamma Irradiation \u2714 Sterile Filtration \u2714 Chemical Methods \u2714","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/","og_locale":"en_US","og_type":"article","og_title":"Sterilization Methods and Aseptic Practice - RCT Magazine","og_description":"Sterilization in Laboratory & Medical Settings \u2013 Autoclaving \u2714 Tyndallization \u2714 UV & Gamma Irradiation \u2714 Sterile Filtration \u2714 Chemical Methods \u2714","og_url":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/","og_site_name":"Reichelt Chemietechnik Magazine","article_published_time":"2019-11-22T10:43:11+00:00","article_modified_time":"2025-12-12T15:41:37+00:00","og_image":[{"width":800,"height":516,"url":"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg","type":"image\/jpeg"}],"author":"Dr. Karl-Heinz Heise","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Dr. Karl-Heinz Heise","Est. reading time":"10 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/","url":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/","name":"Sterilization Methods and Aseptic Practice - RCT Magazine","isPartOf":{"@id":"https:\/\/www.rct-online.de\/magazin\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#primaryimage"},"image":{"@id":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#primaryimage"},"thumbnailUrl":"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg","datePublished":"2019-11-22T10:43:11+00:00","dateModified":"2025-12-12T15:41:37+00:00","author":{"@id":"https:\/\/www.rct-online.de\/magazin\/#\/schema\/person\/de5369aedc25d1f064871d823629e056"},"description":"Sterilization in Laboratory & Medical Settings \u2013 Autoclaving \u2714 Tyndallization \u2714 UV & Gamma Irradiation \u2714 Sterile Filtration \u2714 Chemical Methods \u2714","breadcrumb":{"@id":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#primaryimage","url":"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg","contentUrl":"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2019\/12\/sterilisationsverfahren-und-steriles-arbeiten.jpg","width":800,"height":516,"caption":"\u00a9 romans14 \u2013 stock.adobe.com"},{"@type":"BreadcrumbList","@id":"https:\/\/www.rct-online.de\/magazin\/en\/sterilization-methods-and-aseptic-practice\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.rct-online.de\/magazin\/en\/"},{"@type":"ListItem","position":2,"name":"Sterilization Methods and Aseptic Practice"}]},{"@type":"WebSite","@id":"https:\/\/www.rct-online.de\/magazin\/#website","url":"https:\/\/www.rct-online.de\/magazin\/","name":"Reichelt Chemietechnik Magazine","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.rct-online.de\/magazin\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/www.rct-online.de\/magazin\/#\/schema\/person\/de5369aedc25d1f064871d823629e056","name":"Dr. Karl-Heinz Heise","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.rct-online.de\/magazin\/#\/schema\/person\/image\/","url":"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2024\/07\/KH_Heise.jpg","contentUrl":"https:\/\/www.rct-online.de\/magazin\/wp-content\/uploads\/2024\/07\/KH_Heise.jpg","caption":"Dr. Karl-Heinz Heise"},"description":"Dr. Karl-Heinz Heise studierte an der Martin-Luther Universit\u00e4t Halle-Wittenberg Chemie und der vormaligen Technischen Hochschule Dresden Radiochemie und Chemische Kerntechnik. Danach war er bis zur politischen Wende 1989 als wissenschaftlicher Mitarbeiter am Zentralinstitut f\u00fcr Kernforschung Rossendorf (ZfK) der Akademie der Wissenschaften in verschiedenen Bereichen der Isotopenproduktion und Markierungschemie t\u00e4tig. 1990 wurde er im neu gegr\u00fcndeten Leibnitz-Forschungszentrum Dresden - Rossendorf, dem heutigen Helmholtz-Zentrum, mit der Leitung der Abteilung f\u00fcr Organische Tracerchemie des Instituts f\u00fcr Radiochemie betraut, die sich mit umweltchemischen Prozessen in den Hinterlassenschaften des Uranbergbaus der DDR befasste. Dr. Heise ist begeisterter Hobby-Numismatiker und besch\u00e4ftigt sich dabei vornehmlich mit der h\u00f6fischen Medaillenkunst des 19. Jahrhunderts in Sachsen.","url":"https:\/\/www.rct-online.de\/magazin\/en\/author\/k-heise\/"}]}},"_links":{"self":[{"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/posts\/15440"}],"collection":[{"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/comments?post=15440"}],"version-history":[{"count":12,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/posts\/15440\/revisions"}],"predecessor-version":[{"id":15455,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/posts\/15440\/revisions\/15455"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/media\/12043"}],"wp:attachment":[{"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/media?parent=15440"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/categories?post=15440"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.rct-online.de\/magazin\/en\/wp-json\/wp\/v2\/tags?post=15440"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}