Sterilization with aldehydes

Blood compatible materials are essential for artificial organs which are used in contact with blood. The immunological aspects of blood compatibility are stressed. Complement activation induced by material-blood interaction is most likely related to transient leukopenia during extracorporeal circulation such as hemodialysis. Although transient, it may be harmful, especially if it occurs frequently. Some complications associated with hemodialysis may be caused due to the repeated complement activation and leukostasis in the lung. Cellulosic membranes induce the phenomenon more severely than synthetic membranes. Reused cellulosic membranes sterilized with aldehyde after the first use show less complement activation and leukopenia. Aldehyde treated biological substances may play a important role in enhancing blood compatibility. 

Bacterial spores are the most resistant of all microbial forms to chemical treatment. The majority of antimicrobial agents have no useful sporicidal action, with the exception of the aldehydes, halogens and peroxygen compounds. Such chemicals are sometimes used as an alternative to physical methods for sterilization ofheat sensitive equipment. In these circumstances, correct usage of the agent is of paramount importance since safety margins are lower in comparison with physical methods of sterilization (Chapter 20). 

The oxidative degradation of organic pollutants in water and air streams is considered as one of the so-called advanced oxidation processes. Photocatalytic decomposition of organics found widespread industrial interest for air purification (e.g., decomposition of aldehydes, removal of NO , ), deodorization, sterilization, and disinfection. Domestic applications based on Ti02 photocatalysts such as window self-cleaning, bathroom paints that work under illumination with room light, or filters for air conditioners operating under UV lamp illumination have already been commercialized. Literature-based information on the multidisciplinary field of photocatalytic anti-pollutant systems can be found in a number of publications, such as Bahnemann s [237, 238] (and references therein). 

A problem associated with beef sterilized by irradiation at approximately room temperature is the production of an unpleasant flavor and aroma. This paper summarizes knowledge of the volatile components of enzyme-inactivated irradiated and nonirradiated beef, reviews the effects of concurrent and nonconcurrent irradiation procedures and of storage on these components, and presents evidence that methional (3-methylmercaptopropion-aldehyde), 1-nonanal, and phenylacetaldehyde are of primary importance to irradiation off-odor in beef thus processed. 

Aldehydes Broad spectrum antibacterial, antifungal. Acid solutions inactivated with Chemical sterilization and storage of... 

As seen with other functional classes, the most important compound of the class is usually the simplest member. Formaldehyde, the simplest aldehyde, is a gas at room temperature, but it is often supplied and used in the form of a 37% aqueous solution called/orma-lin. This solution kills microorganisms and is effective in sterilizing surgical instruments. 

Parts molded from polycarbonate can be cleaned, disinfected, and sterilized by most methods known in practical operation. With some materials, caution is advisable if aldehydes or phenols are active ingredients. Under certain conditions, damage in the form of stress-cracks can occur under contact with cleaning, disinfectant, and sterilizing media. They result in a reduction in mechanical strength. Moreover, there also other effects not always visible, such as initial swelling or chemical degradation in the plastic that can also impair mechanical properties. 

Generally, sterility is synonym with the absence of any viable microorganisms including their spores. Currently, the available sterilization methods include heat sterilization (steam and hot-air sterilization), cold sterilization (gas sterilization, sterilization by ionizing radiation), sterilization by aqueous solution (aldehydes, peracetic acid, hypochlorite, hydrogen peroxide), and sterilization by filtration methods. The choice of method is based on recommendations in medicinal literature, legal requirements, and the compatibility of a medical product with the method used. The decision for a particular method has to take the following factors into consideration [954] ... 

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