it is a well known fact that microwaves are great for sterilizing things . they heat water to steam quickly and sterilize like an autoclave.
the average home microwave is very useful for cleaning up filthy porous hydrophilic objects like sponges.
the thought occureed to me that a super clean home product sponge that would be useful for cleaning wounds and such and cleaning blood and goop out would be possible WITHOUT being disposeable if it was just designed specifically for sterilizing in the microwave. more than your average sponge...this spunge is designed to be super sterile as a result of microwaving .
why not? special heat packs have been designed for the microwave. egg cookers, and other objects specifically designed for magnetronic heating.-- teslaberry, Mar 08 2014 If it is a choice between a hand full of leaves and reusing sponges that can be proved sterile... well maybe. Your still putting dead blood cells, sterile street dirt, and recently snuffed cancer cells back in the wounds. Maybe blankets and pillows would be better candidates for sterilizing.-- popbottle, Mar 09 2014 Hmm, don't the waves not exactly heat every bit of the object, as the wavelength is long-ish and bacteria are small-ish....so the spunge might not be 100% sterilised.-- not_morrison_rm, Mar 09 2014 You wouldn't need a direct hit, though, would you, [not_morrison_rm]? I mean, supposing that the sponge was fullish of water, the microwaves would heat the water, and then the boiling water would do the killing. Contra [teslaberry], I doubt it would be as thorough as an autoclave, but it would be as thorough, I would expect, as boiling something on the stove, and more energy-efficient.-- pertinax, Mar 09 2014 [not morrison m], the microwaves in that type of oven are, despite their size, "tuned" to be highly absorb-able by water molecules (lots smaller than bacteria). So, with the water molecules heated to boiling, the bacteria die. Simple!
Don't count on it working so effectively against viruses, however. For them, you might need a microwave oven with an adjustable frequency of the output, so you can set the wavelength to something that some other molecule (maybe DNA or RNA) absorbs strongly.-- Vernon, Mar 09 2014 //the microwaves in that type of oven are, despite their size, "tuned" to be highly absorb-able by water molecules//
No, they aren't.-- spidermother, Mar 09 2014 //I mean, supposing that the sponge was fullish of water
We are talking about two different things, I was referring to the spunge in the 4th line to last line of the post. Very different kettle of ferrets, yer spunge.
But seriously, spidermother raises one point, and there is a problem that there are gaps between where the radiation goes, I got told off on here ages ago cos I suggested microwave ovens to zap mosquitoes. Turns out the little buggers can avoid being flambe-d by just moving to spot with no radiation.
As sponge is not 100% water, fairly obviously, you can't count of convection and conduction across whatever the material the sponge is made out of seems a bit unpredictable.
The defence rests its case, and spunge.-- not_morrison_rm, Mar 09 2014 /can't count on convection/
The ability of steam to move heat from place to place is pretty reliable.-- bungston, Mar 09 2014 How about a boiler add-on? Produce superheated steam by turning a focus point of the magnetron onto sturdy boiler pipes, basically just adapting what's been baked for steam engines. Accumulate some of this if possible, and in all cases feed the output to the oven's steamer closet.
All things needing sterilisation go into said closet for heating well over 40 degrees for enough time.
Doesn't a dishwasher do this?
And if so, would it be worth putting your dirty spunge in with all the clean dishes?-- skoomphemph, Mar 09 2014 // they heat water to steam quickly and sterilize like an autoclave //
They most certainly do not. If that were so then surgical instruments would be sterilized in microwaves and there would be no need for autoclaves. Autoclaves operate at much higher temperatures and more significantly at high pressure. The air pressure inside a microwave oven is never higher than the pressure outside it.-- Alterother, Mar 09 2014 I think the pressure is only significant inasmuch as it allows a higher temperature to be reached without water boiling.-- MaxwellBuchanan, Mar 09 2014 How sterile are the dishes after they've been washed and dried? That would be a better measure of relative sterilization than some near absolute like the medical version of the concept. (Not to mention that it's probably worth risking a few deaths due to domestic pathogen survivals rather than all die from the superbugs we eventually breed in our kitchens.)
So how do you make that sponge sterile _enough_? (and no more). I would say "as sterile as the dishes" - or nearly so.
Then the microwave could be of some use as the heat source for a (medically-) sub-optimal autoclave that does a good enough job on sponges.
Just to chuck something else in the mix: Isn't the objective simply to make the sponge as non-nutritious at possible? (Assuming we don't mind the occasional death due to excessively filthy food.)
If there's nothing for whatever bacteria there are on the sponge to eat, they won't multiply (so good old cold water can do enough cleaning up).
If you medically autoclave a sponge containing a microbial feast, and then irradiate it for good measure, at t=0 after leaving the treatment process, your sponge will contain a nice cooked meal for a growing microbial family, currently starving to death on the edge of your unsteamed, unradiated sink.
At some t = 1 some microbial Space traveller (from that relative perspective) will land on the Planet of Cooked Food (or a survivor of the Great Careless Squirt of Water Disaster, down below, will lead a tribe up into the rich uplands) ...
At some t = n , the microbial population of the nuked sponge will exceed that of the cold rinsed sponge by orders of magnitude.
Nevertheless, I would still like to have a little autoclave simulator heated by my microwave oven.
=== Edit === Or just chuck it into your pressure cooker, and wait for the whistle?-- skoomphemph, Mar 09 2014 You can make a very effective home autoclave by filling a pickling jar with water, sealing it really, really tightly, and then microwaving it on HIGH for, oh, half an hour or so.
Of course you can only do it once per microwave, but microwaves are fairly cheap.-- MaxwellBuchanan, Mar 09 2014 As long as you don't forget to add red dishwashing liquid.
They're not that effective with the green liquid, and are a bit weak with none.-- skoomphemph, Mar 09 2014 And when the spunge in no longer usable, is it exspunged?-- not_morrison_rm, Mar 09 2014 random, halfbakery