If you were an intelligent futuristic robot whose job is to sterilize things (like MO in Wall-E), what kind of visual system would you be equipped with?
You wouldn’t. Bacteria are too small to be effectively discerned through a visual system in the real world. They are too small and the real world is too chaotic. It is akin to looking for opossums in the Amazon from a satellite. If you scan the entire forest/wall you won;t be able to see anything that small. And by the time that you zoom in close enough to be able to see a single organism you are looking at such a small area that the odds of seeing what you want to see are pretty much nil.
If it’s essential to be able to see bacteria with a visual system you need some sort of system to make them fluoresce or otherwise emit a unique signal. That way you can see them as points of light, which are much easier to see in a large area scan. For example you could potentially count car houselights in the Amazon using a satellite. There are various ways you can make bacteria fluoresce. In theory you could tailor your light source to various spectra and read the emissions directly. That system would be a bitch to calibrate but it could work.
There are home camera/microscopes you can hook to your PC.
They can see bacteria.
On a wall? Can you post some images they have provided of bacteria on a wall?
I’m finding this tough to believe because you need 100X oil immersion to be able to see the vast majority of bacteria even when they are in a broth culture, on a glass slide. The idea that a mass produced, domestic grade microscope can see them at all, much less on an opaque surface, is staggering.
Cool idea. Can you give some examples of how to make bacteria flouresce?
One thing to consider is do you care whether the bacteria or bacterial spores are actually viable? I do research in the area of biological decontamination and swab/wipe/vacuum sampling and plating into growth media is pretty much the current standard for determining whether a given area is contaminated or not.
There is one spectroscopic technology that I know of, Laser-Induced Breakdown Spectroscopy (LIBS), that can be used to identify bacteria. I believe it has more potential for identifying mystery powders than establishing clearance goals. Like a microscopic, it can only look at one small area at a time.
That requires genetic engineering – give the bacteria a gene from a jellyfish so that it produces glowing protein. Which isn’t something you should be doing to all of the bacteria in your home…