Antiseptic Effect On Bacteria

Antiseptics are used to treat and prevent infection on skin, but many antiseptic products use different active ingredients to kill or slow the growth of bacteria. Several commonly used antiseptics contain active ingredients include isopropyl alcohol, iodine, chlorohexidine gluconate, and hydrogen peroxide. The use for products with these ingredients also depends on the type of wound since certain active ingredients have different mechanisms for killing bacteria. However, a growing concern in modern medicine is how bacteria can become resistant to antimicrobial agents such as antiseptics. When bacteria is exposed to low concentrations of antimicrobial agents, some of the bacteria can survive and mutate to produce a better line of defense against …show more content…
In particular, many of the sources are studies done by scientists who have observed the effects of antiseptics on bacteria such as E.coli. Websites that focus on microbiology help explain the presence of E.coli in the real world and the uses of E.coli as a popular laboratory bacterium. I also plan on conducting a lab experiment to support or disprove my hypothesis. I will be testing out four different antiseptics on E.coli bacteria while using turbidity and a spectrophotometer to measure bacterial growth. Small test tubes, called cuvettes, will be filled with non-pathogenic E.coli bacteria and a nutrient broth. In addition, a blank cuvette will be used to calibrate the spectrophotometer so that it will properly measure the turbidity of bacteria. Using the spectrophotometer, I will first use the blank cuvette in the spectrophotometer and record the absorbance. The absorbance for each cuvette after the blank (they will be filled with nutrient broth and E.coli) will be recorded. After that measurement, a small amount of antiseptic is applied onto the E.coli in the cuvette and, depending on the antiseptic, a certain amount of time must pass and an absorbance is recorded again. I will compare the initial absorbance for each sample with the absorbance post-application of antiseptic. The antiseptics I plan on using are household 3% hydrogen peroxide, chlorohexidine gluconate, 70% isopropyl alcohol, and iodine solution. I will be testing the antiseptics at the concentration they already have because these antiseptics are bought at that concentration and their practical use usually does not involve additional dilutions. The E.coli bacteria will be diluted using serial dilutions; serial dilutions are necessary in the process of recording how much bacteria there is in a given sample and it prevents bacterial cells from clumping. Some of the sources