Are we talking glass or plastic pipettes? If glass, you might be able to remove the top and soak in rubbing alcohol. I just avoid the whole cleaning part and use plastic. After using one, I label a ziploc baggie with the EO/FO name and drop the pipette in there for next time. I admit it's kinda a pain to rummage thru my box of baggies searching for something specific but I can't bring myself to toss them after a single use.
I wrap them in a 'tube' of paper towel, label the towel with black marker and attach them to the FO bottle in question with a rubber band so I can reuse (all my bottles are kept in boxes so it's clean enough). I used to throw them out after one use but I found that I would run out pretty quickly, even though I buy a thousand at a time! (I do a LOT of blending).
That's a really good idea, Aline! I think I shall start doing that. I use plastic and I normally toss them out after one use, but like you said- they run out pretty quickly. I think I may clean mine with alcohol and let it air-dry first before taping it on the bottle just in case any of the FO degrades/breaks down in the pipette and introduces something undesirable to the FO the next time I use it.
In labs, we get glass test tubes and tape them to the sides of bottles to keep pipets nearby without cross contamination. Little glass test tubes are very inexpensive and would work well in this case! Plus, if they get dirty you can even clean them. The paper towel idea seems interesting. I'm visualizing the same thing as the test tube.
I'm lazy. I turn my pipettes upside down and rubber band them to the EO bottles. That way they are always handy. If they get gross, I toss them. Typically, the rubber bands degrade before the pipettes.
I don't blend that much, but if I am going through a spell of doing a bunch of FO samples at the same time, I do try to reuse the plastic ones (don't have glass.) When I have several dozen at once (otherwise I do just throw them away), I have a container of soapy water standing by, and suck the water in and out several times w/each. Then I mix up a solution of soapy water and a little bit of bleach and do it again. By that time the fragrance and the bleach smell is mostly gone (so far as I can tell), but I cannot swear that infinitesimal residual bleach molecules will not make the FO turn into a morphing monster! It has not for me so far, I think, but your results may vary
Also, even doing a bunch of them at once is a pain in the &*^.
I just squeeze water in & out a dozen or so times and let it air dry. I won't dip one into multiple eo bottles at that exact moment, i use a different one for each scent. But once it's air dried I'll use it for anything.
I reuse mine after rinsing a few times with hot soapy water, then storing upright to dry. I see no reason to throw them away until the bulb doesn't suck up liquid anymore. Transferring scent has not been a problem for me. I am always looking for easy ways to reduce my waste and this one qualifies.