I started to brainstorm
for my project. My question is “How much microorganisms grow on high encounter
contact surface of door handles?” I had a list of objects for the Phoenix
College campus to sample like bathroom door handles, elevator buttons, water
fountain handles, and computer keyboards/ mouse’s in different locations around
the campus. On the other hand, the lab advisor and I decided that little
samples were better for my beginning level of research. In other words, it’s
better to crawl before running. The method/ materials used to perform my
experiment are listed below.
1. Prepared
20 test tubes of 5mL of 0.1% Peptone.
2. Identified
the 4 door handles being swab for the experiment.
3. Dipped
swab in Peptone, and swab each handle with 0.1% Peptone.
4. Swab
handle 20cm across in a vertical or horizontal line. (Depending on handle)
a. Slight
rotation of swab on contact with surface.
b. External
handles are shorter area surface.
5. Each
swab tip was broken off in test tube of Peptone to reduce contamination.
6. Vortex
each sample for 30 seconds and repeated 3 times.
7. Transferred
50µL, 100µL, 200µL samples to TSA plates to for culturing bacteria.
8. Using
the streaking method to obtain pure colonies of bacteria (non-selective).
9. Incubate
for 24 hours at 37°C.
I
learned a lot from gathering information to establish my methods/ procedure for
my experiment. I learned what a TSA a plate is used for in providing enough
nutrients to allow for a wide variety of microorganisms to grow. Using this
media for culture storage, counting, or isolation of pure cultures is
interesting. Moreover, learning about the streaking method of isolation has
started a curiosity.
