Most Effective Hand Cleaner
The purpose of this experiment is to: (a) determine if hand soap or alcohol gel is the most effective in killing Staphylococcus aureus (b) obtain the statistical difference of effectiveness in killing S. aureus between hand soap and alcohol gel. The null hypothesis is that neither hand soap nor alcohol gel is effective in killing S. aureus more than the control group which is nothing at all. The alternate hypothesis is that hand soap versus the control group will be more effective in killing S. aureus and/or alcohol gel versus the control group will be more effective in killing S. aureus. Another alternate hypothesis is that alcohol gel is more effective in killing S. aureus than the hand soap. Materials and Methods:
The bottom of a Trypticase Soy Agar (TSA) plate is divided into three (3) pie sections along with the experimentalist initials, class day and class time. A sample of S. aureus is obtained in a closed lid sample tube. The sample tube is rolled back and forth to suspend the organism evenly while wearing gloves. The sterile swab is dipped into the test tube to obtain S. aureus, and then closed. The petri dish lid is opened just long enough to gently apply the swab in a streak pattern rotating the plate at different angles. The lid is placed on the petri dish and the contaminated swab is disposed in the biohazard bag. A blank disk is placed in the center of section one (1) with sterile tweezers. A second disk is dipped into hand soap and placed in the center of section two (2). A third disk is dipped into alcohol gel and placed in the center of section three (3). Each disk is softly tapped into media to secure. The petri dish is placed bottom side up in an incubator set at 37 degrees Celsius for three (3) days and then placed into refrigerator. Two (2) weeks later the diameter of the zone of clearing around the disk from each section is measured in millimeters. The data is collected from each class...
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