UV sterilisation

Arachidic acid LB fdms were built-up at a surface pressure of 32 mN m using a constant perimeter barrier trough located in a microelectronics clean room. The subphase used was ultrapure water purified by reverse osmosis, carbon filtration, two stages of deionisation and UV sterilisation at a temperature of 20 1 C and pH 5.8 0.2. Y-type deposition was noted with an average transfer ratio of 0.9 (upstrokes and downstrokes). 

Mars rovers, Spirit and Opportunity, could deposit Earth bacteria on the Martian surface, which fortuitously could find an environment in which to colonise. One possible false alarm for Martian life exploration is that evidence is found on the Martian surface of life on Earth. Extreme measures have been taken with the NASA spacecraft to use exposure to the UV radiation from the Sun to sterilise the spacecraft, rotating the various surfaces to face a prolonged exposure, but none of this could guarantee a sterile spacecraft. 

Immerse the mice in methylated spirits and place under a UV light for 5 min to sterilise them exteriorly. 

When an aseptic room is not in use the air may be sterilised by use of UV germicidal lamps. These should be installed in a position such that the whole room is illuminated and should be sufficiently powerful to be effective at the extreme comers of the room. 

Singh, J. P. and Ghaly, A. E. (2006). Reduced fouling and enhanced microbial inactivation during online sterilisation of cheese whey using a UV coil reactor. Bioprocess Biosyst. Eng. 24, 269-281. 

The addition of UV-absorbing organic matter was also discussed to match the presence of humic acids. An attempt to add humic acids to the samples failed, owing to a decomposition of these acids during autoclave sterilisation. It was hence decided to add lauryl sulphate as a compromise for matching the presence of these acids, as was successfully performed for the certification of nitrate in artificial freshwater [5]. The short-term stability study demonstrated that the samples remained stable under the conditions tested. 

Light frequently inhibits the growth of bacteria, although there are species which readily survive in the light (UV light has surface sterilising properties). 

Any plastic constituent in addition to the function it serves must have heat stability, UV light stability, weather resistance, low solubility in terms of extraction, compatibility with other constituents and good dispensability. Where plastics have to be sterilised by irradiation, certain constituents may be degraded, or even continue to degrade after irradiation. Certain antioxidants are degraded by gamma irradiation. 

This is not recognised by the BP or USP as a formal sterilization process. UV light is basically a surface sterilising process and is used in some sterile (class 1) areas to reduce any airborne contamination. 

Resistance to sterilisation process (dry heat, moist heat, irradiation, UV, etc.). 

In the food industry such equipment would use either a presterilised web exposed by a removable peelable layer, or UV or hydrogen peroxide as an on-line surface sterilising agent. Currently none of these would be acceptable for a pharmaceutical operation, although use for sterile oral liquids might bear consideration. 

A 100 mg sample of each coating was cut into small pieces, sterilised by UV light, and then dispersed in 9 ml of sterile saline water (0.85 wt%). 1 ml of bacterial (Escherichia coli or Staphylococcus aureus) culture (10 CFU/ml) was subsequently added to this solution and finally the concentration of polymer in the suspension was diluted to reach 10 mg/ml. The flasks were shaken at 90 rpm for 24 h and the temperature was maintained at 37 °C blanks without the coating were also run. The surviving bacteria before and after shaking were counted using the plate count method. 

PAN is used in packaging (industrial, medical, and food) and as fibre (Orion), mainly because of its chemical and UV resistance, as well as for the retention of flavour and aroma and excellent durability under sterilisation procedures especially in packaging. PAN fibres have wool-like properties and are chemical precursors of high-quality carbon fibres. Almost all forms of PAN are copolymers with acrylonitrile as the main component. As copolymers of acrylonitrile, there is SAN to mention which will be discussed next. 

High-energy radiation such as ultraviolet (UV) radiation, X-rays, y rays and electron beams can initiate polymerisation. Radicals formed into polymeric materials during sterilisation by such radiation have a long life, especially in the bulk of the material, and can initiate new polymerisation. Such an initiation process has been used widely to modify polymeric surfaces by grafting another polymer. 

Although tuna are considered very robust in grow-out and have very few reported disease issues, some diseases and parasite issues have been reported in larviculture. Viruses including viral nervous necrosis (VNN) and iridovirus have been reported in bluefin tuna and incoming hatchery water is often sterilised with UV or ozone to prevent the transmission of such diseases (Munday et aL, 2003 Sawada et al, 2005 Nishioka et a/., 2010). 

Degradable PE samples were sterilised by UV exposure at 254 nm (2x5 min) and inoculated over 30 minutes with a suspension of different strains (bacterium and fimgus). Assays and controls were incubated for six months at 27 °C and 85 % humidity in an environmental cabinet. Cultivations were carried out in Petri dishes containing glass beads and a mineral salt medium [56]. It was observed that the heated films oxidised more rapidly than the control at the end of the induction period. 

Acrylic resins offer exceptional optical clarity, excellent sterilisability, processability, dimensional stability, bondability and excellent UV transmittance. High impact and medium impact grades are available with exceptional resistance to gamma radiation sterilization and superior UV transmission, for in vitro diagnostic use. 

Most of these devices are single-use and so will be sterilised by gamma radiation or by EtO and this will not usually affect the performance of UV adhesives. Some grades of UV adhesives will withstand repeated autoclave cycling (steam at 135 °C) but many grades will deteriorate after a number of cycles and so tests should always be conducted. 

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