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Science Fair Project- Analysis & Discussion

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Science Fair Project- Analysis & Discussion

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Analysis & Discussion
The primary objective of this investigation was to test ultraviolet radiation as an alternative disinfectant for Acanthamoeba in its more resistant cyst form. A previous study had already shown that multipurpose solutions were ineffective compared to hydrogen peroxide based systems at eliminating Acanthamoeba trophozoite contaminations.5 This was a follow-up to that study. Another goal of this study was to test the effectiveness of hydrogen peroxide in eliminating Acanthamoeba cysts as well. Since trophozoites are the more susceptible form of Acanthamoeba, multipurpose solutions tested previously were not evaluated against cysts because they are not effective at eliminating the less resistant form of the organism. From prior knowledge, numerous studies, and from current commercial applications, it has been demonstrated that ultraviolet radiation is a reliable source for disinfecting microorganisms. More specifically, the UVC wavelength (200-260 nm) is microbicidal as compared to other wavelengths.8, The currently available system for contact lens disinfecting using UVC is called the PuriLens System. Only a single published report concerning the effectiveness of this system showed its limited abilities eliminating Acanthamoeba cysts.15 In general, there have been very few studies that tested any type of protozoan cyst sensitivity to UV radiation.8,9 The few studies that have been performed implied that Acanthamoeba cysts are among the most hardy cyst forms and require longer exposure and a higher concentration of UV radiation. 8,9 An analysis of the data showing growth or no growth allowed several observations and conclusions to be made. It seemed that the PuriLens system did an adequate job of disinfecting both Acanthamoeba cysts and trophozoites since no growth appeared on the plates at any time period. The hydrogen peroxide based system also showed satisfactory disinfection of cysts since again no...