The Effect of Different Grades of Expired Amoxicillin on the Growth of E. coli bacteria

To determine the effectiveness of Amoxicillin after the supposed expiration dates, we mixed distilled water, Amoxicillin and Escherichia coli (E.coli) in a test tube and then poured it into a Petri dish filled with agar. After twenty-four hours, the number of E. coli cultures on the plate were counted and recorded. We tested fifteen trials of each group, using Amoxicillin that expired July 1997, May 2004 and the Amoxicillin that will expire in March 2006. It was hypothesized that the medicines effectiveness would correspond inversely with its age, meaning the medicine expiring in March of 2006 would be the most effective and so on. After collecting and analyzing our data with an ANOVA and two 2-Sample T-tests, we determined that our hypothesis was indeed correct. This proves that expiration dates on drugs, at least those on Amoxicillin, are legitimate and should be followed.

Research Done By:

Kelly Haehl
Cousino High School

Kayla Kopke
Sterling Heights High School

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