Science Fair Project- Analysis & Discussion Essay Example

peroxide based system also showed satisfactory disinfection of cysts since again no growth was evident. The homebuilt UV radiator did not eradicate Acanthamoeba cysts with exposure time for less than 15 minutes. The data suggested that Acanthamoeba cysts need at least 15 minutes or more of exposure to UVC radiation in order for complete disinfection.

The growth on the plates at 24 days was confirmed to have decreased significantly from the growth shown at ten days for all of the plates having growth. One problem noted in the PuriLens system before the experiment was that the contact lenses were not being directly exposed to UVC light. However, because the PuriLens system has an agitator, the organisms, sticking to the contact lens are supposed to be dislodged into the solution and then would be in the direct path of the emitted UVC photons. The homebuilt UV radiator was the alternative in order to compare whether or not this would affect the disinfection process of the contacts.The contact lenses in the homebuilt radiator were directly exposed to the UV lamp unlike the PuriLens system, where the contact lenses are slightly blocked from the UV lamp.

There was at least one significant observation of this study that could have altered the results and would need to be addressed in future testing of these disinfecting methods. This observation concerned the amount of growth on the control plates for both cyst and trophozoites. For this study, it was noticed that on the control plate there was a rather small amount of growth on the plates compared to the previous study.Several factors may explain this observation.

The sample of Acanthamoeba that was

delivered may not have been properly handled while being delivered. Since the product was delivered frozen on dry ice and any deviation in the proper thaw time could have affected how many Acanthamoebas were alive, which therefore would have altered the concentration of Acanthamoeba in both the encystation and Peptone Yeast Glucose (PYG) medias. Also, none of the plates actually had an overwhelming amount of growth on them, including the control plates.After the plates were looked at for 10 days and then an additional 14 days, it appeared that there was actually less growth present on the control trophozoite plate after the longer incubation time. This could mean that the Acanthamoeba was perhaps not incubated at the ideal temperature for this particular strain.

Previously published studies used a variety of temperatures from 28 to 35 degrees Celsius. Incubating the medias and plates at a higher or lower temperature may have enabled more vigorous growth. More reliable observations could be made with additional trials.It would also be advantageous to be able to quantitatively analyze all of the growth of each of the plates for an enhanced comparison. This would require more sophisticated laboratory equipment and expertise. Testing all three systems on a variety of Acanthamoeba strains since several are known to be potentially pathogenic to humans could expand this experiment as well.

Also testing these methods on other organisms known to infect contact lenses such as the highly pathogenic Fusarium could further expand these investigations. REFERENCES 1. Guttman, Cheryl. "Acanthamoeba keratitis increasing at an Alarming Rate.

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