Effects on Disinfectants and Antiseptics on Bacteria!!!!

Disinfectants and antiseptics are both products that are used to kill bacteria, but they only work on certain things or surfaces.  Disinfectants, such as bleach, can only be used on non-living things, but antiseptics, such as soaps, can be used on the body.  The only substance that can be used as both disinfectants and antiseptics is alcohol. 

What did you do?

In our recent lab, we swabbed different surfaces with different antiseptics and disinfectants.  We took cotton swabs and dipped them in distilled water and rub it other our index finger and we streaked the cotton swab over the agar.  We did the same thing for the next two step but we used alcohol and washed our hands.  Now we move onto the surface. Everyone swabbed their own hands, but we also had to swab a surface we thought would be the most contaminated.  I decided to swab the toilet seat in the girls bathroom.  We followed the same concept as the skin but instead of washing the surface we used bleach on it instead, since it is an disinfectant.  Then we stuck our petri dishes in the incubator to allow our bacteria to grow.

Results

After 24 hours we took our dishes out and looked at the bacteria cultures that were growing in the agar.  The bacteria I gathered with the alcohol had little or no growth at all, the same went for the soap and bleached bacteria, but the control bacteria was the worse.  This is bacteria from the skin or the surface that didn't have any disinfectants or antiseptics, and these were the most contaminated areas.  After the petri dishes has been in the incubator for at least 48 hours, we took them out and gram stained them.  This is a process used to figure out whether the bacteria is gram-positive or gram-negative.  We heat fixed out bacteria and then looked at it under a oil immersion lens and I discovered that the bacteria I had found on the toilet seat was gram-positive, because it was purple, and its shape was staphylococci, because of its grape like structure.

LAVA LAMPS!!!!!!

Lava lamps were originally called Astro Lamps and were created by Edward Craven.   The lava lamp contains wax, water, and other contents that are all combined together with a secret formula.  How does it work you ask?  Well as the lamp heats up the wax in the lamp melts, and as it melts it becomes liter and it floats to the top.  But how does it come back down?  As it moves away from the light source it cools and becomes heavy once more and falls back down. 

Home made lava lamps are a little different.  Instead of having a heat source, we use salt or Alkaseltzer tablets to make the water bubble. When you combine the water and the oil they don't mix because the oil is hydrophobic and the water is heavier than the oil so it will sink to the bottom.  If you wanted to you could add food coloring to your lava lamp but this will only effect the water because it is hydrophillic.  When you put in the Alkaseltzer tablet you will notice that the water starts to bubble.  This is because the water is causing the tablet to release all of its oxygen and it all goes to the top. This is how home made lava lamps are made.