Hydrolysis : moist heat sterilisation (dry saturated steam rather than superheated/supersaturated steam used-- heat: dry saturated steam @ 121C and 15PSIG contains sensible heat (218BTU/lb) and "latent heat"- the quantity of heat absorbed/released from a substance, suach as ice changing to water/water to steam @ constant T,P- (946BTU/lb), hydration: dry saturated steam + cooled bac.spore i autoclave, steam condenses and hydrates (nt oxidises) the spore. Te layer of condensed H2O imporves heat transfer (rapid!), penetration: rapid-- cotton, wool dressings
bench autoclave, downward displacement autoclave (bottles, surgical instruments), porous load autoclave (bottle fluids, instruments, glassware)
Oxidation : dry heat sterilisation, used when cold conditions must be applied
substances that cannot be subjected to moisture H2O soluble powders (heat stable), materials nt penetrable by steam (ols, fats, waxes), glassware, instruments (forceps)
Alkylation : gases: ethylene oxide (plastic, glass made delicate, complex apparatus), formaldehyde, LTSF, can be used in absence of heat, but sterilisation process is too long
Free radical formation: ionizing radiation (γ-radiation, Xrays, accelarated e-s)
disposable plastics, syringes, catheters, petri dishes, radiation stable ointments and solutions (eye drops)
Chemical Lesions (pyrimidine dimers) of DNA : non-ionising radiation (UV radiation/electromagnetic radiation)
disinfect clean surfaces- laminar flow cabinet after use, cleaned and exposed to UV to reduce contamination, also reduce microbial levels in H2O
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