Concerns

Hi guys!

I think we should be really careful about not only the specificity of our test(s) but also the sensitivity. We should avoid the pitfalls associated with developing a prototype that works for the identification of a given bacteria (or family of bacteria) but fails to do so before concentration levels are far above what is considered safe.

Using a sticker for airborne bacteria identification poses the problem of sensitivity. The amount of bacteria needed to be present on the sticker, in order to lead to a visible color change, would need to be impracticably high.

One idea that has crossed our minds is the use of wet absorbent paper to wipe surfaces. The wet paper would in theory collect bacteria growing on hospital surfaces, even utensils and bed sheets. It would be put in contact with a second paper, which had been previously embedded with the appropriate chemicals. This approach may be more viable for our endeavors and goals.

Another thought is that color changes may be more obvious in liquid phase. Most of the tests we are considering are based on bacterial enzyme activity. Since many bacteria share many similar enzymes which would render difficult a reliable identification, having multiple tests on a same strip/kit/device seems ever more and more appealing.

One can already find in the market biochemical identification kits for microorganisms. 
http://www.oxoid.com/uk/blue/press/press.asp?art=Y&arch=N&pRef=PR0373&c=UK&lang=EN

Thoughts? Any input would be very much appreciated :)

-Thais

PS: Special thanks to Jacqueline Linnes who introduced us to the biomedical identification kits.