Yesterday's entry on Dithiothreitol garnered one lone comment. Remarking on the smell. True enough; it's a thiol - where there's sulfur, there's often stink. There is a biologically compatible reducing agent that doesn't stink at all: tris(carboxyethyl)phosphine, or TCEP.
It's usually sold as the hydrochloride salt. Interestingly, phosphines almost always stink too, but TCEP is nonvolatile, since it's charged. It's oxidized to the phosphine oxide (which are often quite insoluble, but the charges save you again here):
I've never actually used TCEP, but I've had a bottle of it in the fridge for about a year now. Anyone have any experience with it?
- Log in to post comments
More like this
Despite generating a surprising number of comments with last week's burning question (thanks to Kate for the suggestion), we didn't actually go see X-Men III until yesterday afternoon. Short verdict: Not quite as bad as I was led to believe.
The longer version is either on Kate's LiveJournal, or…
Wow everyone! Thanks for all your suggestions on my last post. I thought I'd respond here, since my comments are plenty long enough.... I'll probably still miss some things though.
Re: pumping and breastfeeding. I am planning to nurse on the plane and during the conference proper. Unfortunately the…
“This whole Santa Claus thing just doesn't make sense. Why all the secrecy? Why all the mystery?
If the guy exists why doesn't he ever show himself and prove it?
And if he doesn't exist what's the meaning of all this?” -Calvin, via Bill Watterson
This is our last comments of the week for 2015, and …
Kameron Hurley did a blog post on what it took her to become a writer, which I ran across via Harry Connolly's follow-up. These are fairly long, but well worth reading for insight into what it means to be a writer-- and they're both very good at what they do. You should buy their books, right now.…
I use TCEP immobilized on styrene beads. It works well for reducing disulfides to thiols in proteins and peptides as Chris Hawkins mentioned. Plus, you can easily remove the TCEP beads by centrifugation.
Posted by: RC Fuson | April 25, 2007 9:07 AM
Dear RC Fuson,
I would like to humbly ask you to let me have the method of immobilisig TCEP onto polystyrene beads. This sounds absolutely interesting, so I would love to try it myself.
could you possibly help?
If this message reaches you kindly reply to my email address, because ordinarilly I do not visit this website
Thank you
Martin Schmitt
I don't have any experience with it, but the link below says it's used for selectively reducing disulfides to thiols and lists some journal references.
http://www.soltecventures.com/New%20Product1.htm
TCEP would be pretty useful for keeping thiols (say, on a protein) in their reduced state in order to modify them with a thiol reactive moiety (e.g. a fluorescent molecule; DTT is unusable because it would soak up the thiol-reactive molecule) however TCEP is really expensive last time I checked.
I use TCEP immobilized on styrene beads. It works well for reducing disulfides to thiols in proteins and peptides as Chris Hawkins mentioned. Plus, you can easily remove the TCEP beads by centrifugation.
TCEP is great; I prescribe it to biologists with pesky disulfide problems; especially since the reduction is *irreversible*. Also it has a pretty phat nucleophilic mechanism of action so I can push some arrows and make the biologists look dumb.
Whitesides invented the stuff, I believe.
I know TCEP only as Tri(carboxyethyle) phosphine oxide. I wrote my PhD thesis about it. It has (had?) a wide commercial use as flame retardant. It is relatively untoxic, but causes highly specific brain damages at elevated dose levels. Due to the volume used worldwide it was tested in the 90s by the NTP standard carcinogenicity bioassay. The result was: not carcinogenic in mice, not carcinogenic in female rats, carcinogenic in kidney of male rats. This means a high species-selectivity, high gender selectivity and high organ selectivity. Therefore the probability of a specific carcinogenicity mechanism, which is not relevant to humans is high.
I spent four years of my life on tests, designed to elucidate whether TCEP induced kidney tumors in male rats by a mechanism, which is not relevant to humans. Unfortunytely I was not successful. Therefore TCEP has to be classified as probably carcinogenic to humans.