Sterilization of medical devices

ISO 11737-1. Sterilization of Medical Devices, Microbiological Methods—Part 1 Estimation of Population of Microorganisms on Products. Switzerland (1998). 

W.E. Hall, Cleaning in pharmaceutical facilities—So what s the big deal In Booth, A. F. (ed.). Sterilization of Medical Devices. Buffalo Grove, IL Interpharm Press, 1999, p 289. 

Steam sterilization of medical devices Is used In Japan. It has the advantage of facilitating removal of water soluble residues left after membrane manufacturing, but requires that the device be shipped filled with water. Steam sterilization appears to alter the pore structure of hydrophobic membranes, despite the fact that their glass transition temperatures may be quite high, for example, the permeability of polysulfone membranes Is altered above 70°C. Literature Cited... 

Guideline for Industrial Ethylene Oxide Sterilization of Medical Devices" Association for the Advancement of Medical Instrumentation Arlington, VA, 1981. 

Electron accelemtors are utilized in industrial processes such as crosslinking of polymers, curing rubbers, curing paints and adhesives, sterilization of medical devices and pasteurization of foodstuffs. 

The Canadian Standard for Industrial Sterilization of Medical Devices by the Steam Process, 1979 [II] differentiates between products intended to come into contact with compromized tissue, which are required to have an SAL of 10 (quoted as a probability of being sterile of 99.9999%) and prcxlucts not intended to come into contact with compromised tissue, which are required only to have an SAL of 10 (a probability of being sterile of 99.9%). No other formally admowledged exceptions to the general rule of sterility being defined as a 10 SAL are known. 

Canadian Standards Association (1979). Industrial sterilization of medical devices by the steam process. C5A Standard Z514.4-MI979. Rexdale. Ontario, Canada Canadian Standards Association. 

Electron irradiation is useful in other areas, too. Foods can be irradiated, thereby allowing sterilization, and stabilization(g). For example, irradiation of potatoes kills any bugs, bacteria, etc., and eliminates germination/sprouting, which allows a great enhancement in storage-ability. Bectron irradiation is increasingly used in sterilization of medical devices and equipment(Z), and may even have promise in treatment of various waste streams. ... 

Processing food to ensure safety requires the reduction of viable endospores to a negligible level. Because it is impossible to ensure that all spores are completely eliminated, a standard reduction rate of 10" has been accepted. That means that one surviving endospore for each 10 cans processed is acceptable. Through a combination of temperature and time, thermal processes for food sterilization can be designed (Teixeira, 1992 Johnson, 1999). Similar considerations are important for the sterilization of medical devices and bioreactor growth media. 

Radiation processing by electron beam or y-irradiation is a commonly employed method for the sterilization of medical devices. The method has on one hand the advantage that sterilization can be carried out with the items in their original packages. On the other hand, dosimetry is required to ensure that the radiation treatment is at a tolerable level to avoid toxicological hazard as emphasized in the standards on radiation sterilization drafted by international standards organizations. Dosimetry... 

A number of sterilization methods are used for medical devices. Hiese indude gamma inadiation, steam, electron beam, cold plasmas, and antibacterial agents. Because of the importance of device sterilization to the health of the patient, and because of the potential of sterilization methods to damage polymeric biomaterials, sterilization of medical devices is a field unto itself and is described elsewhere. 

Mendes GCC, Brandao TRS, SUva CLM. Ethylene oxide sterilization of medical devices a review. Am J Irtfect Control 2007 35(9) 574—81. 

Since radiation tolerance is not a characteristic of all PPs, the screening of PP samples for this property is a common endeavor. For the most part, data reported in the scientific literature has relied upon Co ° y as the radiation source. This is due to Co s widespread use and acceptance and the ready availability of providers of contract irradiation services utilizing this method. [1] There are only a few references that deal with EB effects. [7] This limited information suggests that at comparable doses EB causes no more damage to PP than does y radiation, and is most likely slightly less harmful. To date, the effects of sterilization doses of X-radiation fi om EB source on PP has never been reported. Since y, EB, and X-radiation are all now available for the commercial sterilization of medical devices, a comparison of the effects of these three sources of ionizing radiation on a widely used material like PP is in order. This paper reports the results of experiments carried out to compare the response of several types of PP to sterilization doses of ionizing radiation Irom three sources y from Co ° EB fi om accelerators, and X-radiation derived from EB sources. 

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