60 Petri Dish

The ten Petri dishes that exclusively did not contain an antibiotic in the bacteria culture served as the control. There were ten trials for the control and each level of IV. The experiment began by cleaning the work area and sterilizing it with 70% ethanol. Then trypticase soy agar (TSA) was poured into six groups of 60 Petri dishes (See Appendix 1). The dishes were labeled based on the antibiotic used and were left to dry and solidify at room temperature. After an hour, the dishes were placed in a refrigerator at three degrees Celsius. If there was visible condensation on the agar plate, they were flipped to avoid the contact of heat that drove the moisture out of the agar dishes. The contents of the broth culture of E. coli was gently swirled
coli on the plates of TSA. The swab was dipped into the test tube containing the E. coli bacteria culture and was swiped delicately over the agar surface of the 60 Petri dishes (See Appendix 2). In order to ensure that the entire surface area of the dish was covered, the E. Coli bacteria culture was swabbed in at least 3 different directions. The different types of antibiotics were applied to each of the agar plates by using five sterile forceps for each antibiotic. The forceps were cleaned with the ethanol disinfectant before using it again for another Petri dish. The forceps were used to pick up the 60 antibiotic discs and dip them into their corresponding antibiotic solution. This ensured that the IV would receive the same amounts of the solution for each of the Petri dishes. The antibiotic discs were placed at the center of the Petri dish according to their labels and the plates were wrapped with Parafilm. The dishes were incubated for 24 hours at 37 degrees Celsius. The procedure allowed for the IV to be controlled because of the incubation. This allowed the Petri dish to stay sterile and also protected against foreign bacterial exposure during the