August 7, 2006
Saturday night, shortly after that oxalic acid rant, I think I started cracking up. If ever there were a reason not to work alone in lab, this is it. I was standing in front of the rotovap watching the toluene crawl over, ie watching paint dry, when I started idly picking my ear. A huge chunk of wax came out. I stared at the gooey mass and wondered to myself what’s in there?
I had a vague recollection of a 5.08 lecture about the biosynthesis of cholesterol from squalene, and how the latter is a major component of earwax. There’s at least one way to test that hypothesis. I had NMR time anyway so I figured what the hell. I scoped all 36 milligrams of my waxy secretion into a test tube and took it up in CDCl3. I was expecting it to go into solution freely, but there was a mass of material that wouldn’t dissolve even with sonication. So I filtered it through Celite and ran 16 scans on the 400 (vide supra).
Um, yeah. Kind of a greasy mess but still cleaner than a lot of other NMRs I’ve taken. Perhaps more telling were the TLCs that followed. After checking the Wikepedia entry I learned my 5.08 memory about squalene was correct, also that cholesterol itself is a component. So I co-spotted my earwax (EW) against cholesterol (C) and squalene (SQ). Both were in there, along with some unidentified component with an intermediate Rf that streaks a bit.
No clue what that is. -addition- One of the commenters proposed that the middle spot is lanosterol; biosynthetic intermediate on the way from squalene to cholesterol. I TLC’d my earwax against the bottle of “practical” grade lanosterol (L) from the stockroom. Lo and behold:
The entire choreographed ballet that is the HMG-CoA reductase pathway being played out in my ear! It’s a beautiful thing.
 I have this CDCl3-insoluble fraction of my earwax set aside. Perhaps at some future date I’ll see if that’ll go into DMF-d7.
 In a weird way, this is the most detailed personal information I’ve ever disclosed on the web. Not sure how I feel about that. Maybe some other people could send me TLCs and NMRs of their earwax; I’ll put them in a gallery. Evidently earwax composition varies among ethnic groups, so we can look into that as well.
 If you think this was a waste of time I’d like to point out that more than one person has made a career out of earwaxology… see the Wikipedia references.