What is ionizing radiation sterilize?
Ionizing radiation is the use of short wavelength, high-intensity radiation to destroy microorganisms. This radiation can occur in the form of gamma or X-rays that react with DNA, leading to cell damage.
How does ionizing radiation kill bacteria?
The bottom line is that ionizing radiation destroys the subatomic particles involved in microbial formation. In short, this radiation destroys DNA or RNA, the genetic material of living cells. If the DNA or RNA of a microorganism is damaged, the cell will die. In other words, radiation can damage the bacterial hard drive, causing it to shut down permanently.
Ionizing radiation relies on ionizing radiation, primarily gamma, X-ray or electron radiation, to deactivate microorganisms.
Why is radiation used for sterilization?
Radiation have a high penetration power so materials can be sterilized after filling them in the final container.
The method is suitable for all types of materials such as dry, moist and even frozen items.
The method is considered to be reliable and can be accurately controlled.
What products are sterilized by using radiation?
Medical instruments
Used to sterilize human tissue grafts: Allogeneic connective tissue grafts, such as bones, cartilage, tendons, ligaments, dura mater, skin, heart valves and cornea, have been widely used in plastic surgery in many clinical fields. Including orthopedics, traumatology, neurosurgery, cardiac surgery, plastic surgery, laryngoscopy and ophthalmology.
Radiation sterilization is also used to sterilize plastic syringes, hypodermic needles, scalpels, scalpels, adhesive dressings and heat-labile drugs.
Other applications include: syringes, surgical gloves, gowns, masks, plasters, dressings.
Cosmetic
Food
-
Beef and Pork.
-
Crustaceans (e.g., lobster, shrimp, and crab)
-
Fresh Fruits and Vegetables.
-
Lettuce and Spinach.
-
Poultry.
-
Seeds for Sprouting (e.g., for alfalfa sprouts)
-
Shell Eggs.
-
Shellfish - Molluscan.
New Materials
-
1. Radiation cross-linked polyethylene
-
2. Heat shrinkable material
-
3. Foaming and water-absorbing materials
-
4. High-strength medical silicone rubber, etc.
-
5. Preparation of polymer composite materials, nanomaterials, etc.
How does food radiate?
Three sources of radiation are approved in food.
Gamma rays are emitted from the radioactive form of the element cobalt (cobalt 60) or cesium element (cesium 137). Gamma rays are commonly used to sterilize medical, dental and household products, and are also used for radiation treatment of cancer.
X-rays are produced by reflecting a stream of high-energy electrons from a target substance (usually one of the heavy metals) into the food. X-rays are also widely used in medicine and industry to produce images of internal structures.
The electron beam (or electron beam) is similar to X-rays, and is a stream of high-energy electrons propelled from an electron accelerator into food.
Does ionizing radiation sterilize?
Radiation kills germs that can cause disease and neutralizes other harmful organisms. Sterilization with ionizing radiation inactivates microorganisms very efficiently and, when used for product wrapping, ensures that healthcare products are safe and can be relied upon.
Ionizing radiation and Non-ionizing radiation
Ionizing radiation is the use of short wavelength, high-intensity radiation to destroy microorganisms.
Non-ionizing radiation uses longer wavelength and lower energy. As a result, non-ionizing radiation loses the ability to penetrate substances, and can only be used for sterilizing surfaces.
Irradiation can have many uses.
Prevent foodborne diseases-effectively eliminate organisms that cause foodborne diseases, such as Salmonella and E. coli.
Preservation-destroy or inactivate organisms that cause spoilage and decomposition, and extend the shelf life of food.
Insect control-Destroy insects in or on tropical fruits imported into the United States. Irradiation also reduces the need for other pest control measures that may harm the fruit.
Delayed germination and ripening-inhibit germination (eg potatoes) and delay fruit ripening to extend life.
Sterilization-Irradiation can be used to sterilize food, which can then be stored for many years without refrigeration. For patients with severely compromised immune systems in hospitals (such as AIDS patients or patients undergoing chemotherapy), sterilizing food is very useful. Foods sterilized by irradiation receive a much higher level of treatment than foods approved for general use.
What are the types of ionizing radiation sterilization?
Gamma rays: gamma rays are highly penetrating and are commonly used for disinfection of disposable medical devices, such as syringes, needles, cannulas and intravenous infusion sets, as well as food. Gamma rays are emitted from radioactive isotopes (usually cobalt 60 or cesium 137). Cesium-137 is used in blood treatment before blood transfusion in small hospital units to prevent graft-versus-host disease. The use of radioisotopes requires shielding to ensure the safety of operators during use and storage, as these radioisotopes continuously emit gamma rays (which cannot be turned off). An incident in Decatur, Georgia, in which water-soluble cesium-137 leaked into a source storage pool requiring NRC intervention, resulting in the near disappearance of the radioisotope. It has been replaced by the more expensive insoluble cobalt 60. In some cases, gamma irradiation sterilization may affect the properties of the material.
Electron beam: electron beam processing is also commonly used for sterilization. Electron beams use on-off technology and provide higher dose rates than gamma or X-rays. Due to the higher dose rate and the need for less exposure time, any potential degradation of the polymer is reduced. The limitation is that the electron beam is not as penetrating as gamma rays or X-rays. The facility relies on strong concrete shielding to protect workers and the environment from radiation.
X-ray: high energy X-ray is a form of ionization energy, which can irradiate the large package and pallet load of medical equipment. X-ray sterilization is an electrical based process that does not require chemical or radioactive materials. X-ray machine generates high-energy and high-power X-rays, and the X-ray machine can be shut down when not in use, so there is no need for any shielding during storage. Irradiation with X-rays or gamma rays does not make the material radioactive.
Subatomic particles: subatomic particles can penetrate more or less and can be produced by radioisotopes or devices, depending on the type of particles. The irradiation of particles may make materials radioactive, which depends on the type of particles, their energy and the type of target materials: neutrons and very high energy particles can make materials radioactive but have good permeability, while particles with lower energy (except neutrons) can not make materials radioactive, but have poor permeability.
Advantage:
-
The medium does not degrade during sterilization, so it can be used in thermally unstable media,
-
No chemical residue left
-
Management of precise dose and uniform dose distribution
-
The medium can be used immediately after sterilization
Cobalt 60
The self decomposition of cobalt 60 (60Co) forms gamma rays for aseptic treatment. Of the thousands of gamma ray emitters, only cobalt 60 is designated for sterilization.
27Co59 + n→27Co60. Cobalt 60 is manufactured specifically for the irradiation process and is housed in a specially designed chamber operating in accordance with strict standards and regulations.
