[Taxacom] Palcohol?

[Ken Kinman]

Hi all,
      I've never stored insects in alcohol, but I've read that both ethanol and isopropanol can make them brittle (some say ethanol is worse, others say isopropanol is worse).  But there does seem to be agreement that concentrations above 70% of either of them can definitely make them brittle.  Anyway, I am wondering if the addition of glycerol helps mitigate that problem.  A few of my spider specimens were saved from dehydration when the alcohol evaporated over the years, but the glycerol kept them moist.                             -----------------Ken                   P.S.  I couldn't find anything about DNA being trashed by isopropanol.  It is often used to extract DNA, so does it only trash the DNA over a long time period?  Most of my spiders were collected in the 1970s.  

------------------------------------------------------------------------------------------------------------

> On 22.04.2014 13:15, John Noyes wrote:
> > Apart from trashing DNA, it also trashes many types of smaller
> > insects by making them so stiff that the become difficult/impossible
> > to card-mount or put on slides. The same also goes for IMS.
> >
> > John
> >
> > John Noyes
> > Scientific Associate
> > Department of Life Sciences
> > Natural History Museum
> > Cromwell Road
> > South Kensington
> > London SW7 5BD
> > UK
> > jsn at nhm.ac.uk
> > Tel.: +44 (0) 207 942 5594
> > Fax.: +44 (0) 207 942 5229
> >
> > Universal Chalcidoidea Database (everything you wanted to know about
> > chalcidoids and more):
> > www.nhm.ac.uk/chalcidoids 
> >
> >
> > -----Original Message-----
> > From: taxacom-bounces at mailman.nhm.ku.edu
> > [mailto:taxacom-bounces at mailman.nhm.ku.edu] On Behalf Of Daniel 
> > Janzen
> > Sent: 22 April 2014 22:38
> > To: Neal Evenhuis
> > Cc: taxacom at mailman.nhm.ku.edu
> > Subject: Re: [Taxacom] Palcohol?
> >
> > It is my understanding that isopropyl alcohol trashes DNA or
> > otherwise makes it very difficult to extract.  Think on that for
> > pickling museum specimens.  I know of no circumstance where you can
> > get (or ship) isopropyl but not get (or ship) 80-95% ethanol.
> >
> > Just a thought.   Dan Janzen
> >