Ready, Set, Go!

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.