S-35 volatility

[nicholjj@lldmpc.dnet.dupont.com]

A member of our research staff brought to my attention an article in the 
February 24, 1995 issue of Science Vol. 267, pages 1186-1187. The article
describes S-35 volatility problems associated with the use of alpha S-35
dATP as a label in polymerase chain reaction (PCR) based procedures.

We have been aware of S-35 volatility problems with methionine and similar labeled material produced during incubations but this appears to be another
matter. With the PCR procedure the article reports researchers have noted
the radioactive decomposition diffused through the tube caps. The end result
being contamination of the PCR machine.

Have any of you encountered this problem? If so, how are you dealing with it?
Suggestions in the article include substituting P-33 labeled nucleotides as
the label, dedicating a thermocycler for radioactive work, and placing the 
thermocycler in a fume hood (especially those without heated lids).

I would be interested in your thoughts on this.

Thanks.

John Nicholson
DuPont Merck Pharmaceutical Co.
Wilmington, Delaware
phone: 302 695-7211
fax: 302 695-7741
e-mail: nicholjj@lldmpc.dnet.dupont.com