#amoeba #microscope #science #biology #experiment

Ever wondered what happens to germs when you clean or sanitize something? In this video I show you how different sanitizers and cleaners such as bleach, dish soap, hydrogen peroxide, rubbing alcohol, and even salt and baking soda affect and kill germs. To demonstrate that I’m using some unicellular organisms including amoebae. However, these cells are eukaryotes and they resemble our own cells more than bacteria and viruses. But as they are much larger, it’s much easier to observe the mechanism by which these chemicals kill them. Keep in mind that some bacteria may be more resistant than these cells, especially those that form spores.
Hope you like this and please let me know if you have any suggestions!

**Update** People are horrified with what happens to microorganisms, so they might be interested to see what happens to animals in a global scale, highly recommend this documentary:
   • Dominion (2018) - full documentary [O...  
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Why is 70% ethanol or isopropyl alcohol better than 100% solutions? Isn’t it better to use 100% alcohol?

Well actually no! Ethanol and IPA are most active when they are mixed with water and the optimum activity is at 70%. Alcohol kills bacteria mainly by denaturing their proteins and dissolving their membrane. 100% ethanol or IPA can coagulate the proteins instantly and create a protein layer that protects other proteins from further denaturation. Furthermore, this layer doesn’t allow water to penetrate and rupture the membrane. Solutions more concentrated than 91% IPA may kill some bacteria, but require longer contact times for disinfection. Such solutions enable spores to lie in a dormant state without being killed. Moreover, addition of water lowers the evaporation rate and hence provides a longer contact time which results in killing microorganisms more effectively. It is also less flammable and more economical! Overall, once alcohol concentrations drop below 50%, usefulness for disinfection drops sharply.
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Experimental details:
-Desired magnification was obtained using either 4X or 10X objective lenses. Please note that this is not the final magnification obtained via the camera digitally.
-I used concavity microscope slides to be able to image a large area and also for the ease of addition of other chemicals to it.
-The culture I'm using is Amoeba Proteus. I don't know what the other small microorganism is.
-I also purchased the original amoeba culture from Amazon and then expanded the culture further. This is how I prepared the media:
Chalkley’s Stock Solution 10x (Synthetic Pond Water)
In 100 mL water:
CaCl2 0.06 g
NaCl 1.00 g
KCl 0.04 g
+2 grains of rice (or wheat) per 50 mL culture.
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My microscope:
AmScope T600A-PCT-DK Professional Phase-Contrast Compound Trinocular Microscope
https://www.amazon.com/gp/product/B00...
My camera:
Swiftcam 16 Megapixel Camera for Microscopes
https://www.amazon.com/gp/product/B07...
Ref:
https://books.google.com/books?id=3f-...
https://www.flinnsci.com/api/library/...