Re: CNBr
Rod Levine (rlevine@nih.gov)
Wed, 18 Feb 1998 18:52:07 -0500
At 05:27 PM 2/17/1998 -0800, Joan Martin wrote:
>
>I wish to do a cyanogen bromide cleavage of a 72 aa peptide and wish to
>avoid lyophylization to dryness of the cleavage mixture. There will be
>about 400 ug cyanogen bromide in the reaction that I wish to HPLC separate
>the two fragments for sequence determination. My concern is trapping
>and disposing of any hydrogen cyanide or other toxic by products in the
>reaction,
>concentration or separation steps. I have a cold trap and chemical
>trap (acid vapours) before the pump on my speed vac concentrator.
Joan,
We don't hesitate to use the SpeedVac for removal of CNBr et al after
cleavages.
However, if you wish, you can add a stoichiometric excess of dimethyl
sulfide to react with any residual CNBr. If you don't want to use such an
perfumed compound, then just throw in methionine.
Of course, you'll still have HCN, but it will be trapped nicely in your
SpeedVac trap.
Rod Levine
NIH
Bldg 3, Room 106 MSC 0320
Bethesda, MD 20892-0320
email: rlevine@nih.gov
voice: 1 (301) 496-2310
fax: 1 (301) 496-0599