The purpose of this experiment was to determine if bacteria acquires a resistance to hand sanitizer and/or antibacterial soap, and at what concentrations.  The E. coli was treated with a low concentration (half transfer loop) and a high concentration (whole transfer loop) of each treatment. Seven Petri dishes, each containing three trials, were set up for each combination of treatment and concentration.  Each dish was grown for four generations and the three trials in the final generation were used as the data.  The area of inhibition, or bacteria-free region between site of treatment and growth of E. coli, was measured for each.  By way of the data produced, it was determined that while concentration seemed to determine the speed of resistance, all developed it.  Furthermore, hand sanitizer developed complete resistance and extremely fast.  Altogether, the low concentration of hand sanitizer became the most resilient while high concentration of antibacterial soap developed the least resilience by far.

Research Done By:

Arianna Moss
Lakeview High School

Cedar Pieprzyk
Warren Mott High School