lyophilizing leaf tissue

Yoram Gerchman via methods%40net.bio.net (by gerchman from research.haifa.ac.il)
Fri Nov 27 02:15:04 EST 2009


While I totaly agree that extracting and sending the extract might be easier,
"Total" lipid extraction could be trickier then one would think. You might
watnt to take a look at this link
<http://www.lipidlibrary.co.uk/topics/extract/index.htm> and at the original
Folck papaer <http://www.jbc.org/content/226/1/497.full.pdf+html>.
Yoram


Quoting methods-request from oat.bio.indiana.edu:

>
> Message: 3
> Date: Thu, 26 Nov 2009 12:34:24 -0400
> From: "Dr Engelbert Buxbaum" <engelbert_buxbaum from hotmail.com>
> Subject: Re: lyophilizing leaf tissue
> To: methods from net.bio.net
> Message-ID: <op.u30gbmaz66vu6s from bengelbert-dm.rusm.rossu.loc>
> Content-Type: text/plain; format=flowed; delsp=yes;
> 	charset=iso-8859-15
>
> Am 24.11.2009, 09:46 Uhr, schrieb Jeremy Coate <coatej from gmail.com>:
>
> > Hi savy methodologists,
> >
> > I need to lyophilize leaf tissue prior to shipping overseas. The tissue
> > will
> > be used for analysis of lipids, which are vulnerable to endogenous
> > lipases,
> > so I am planning to collect the tissue into liquid N2, freeze dry and
> > ship
> > on dry ice to try to ensure that these lipases don't have a chance to do
> > their thing. I have never used a lyophilizer and have concerns that I'm
> > using it incorrectly, and that the samples are thawing.
> >
> > I'm using a Labconco FreeZone 18 freeze dryer with a bulk dryer unit on
> > top
>
> You should have somebody show you how to use the instrument correctly.
> That only takes 2 min, rocket science it ain't. Lyophilizers consist of a
> vacuum pump and a cold trap. You connect your deep frozen sample to it,
> and the solvent (water in your case) sublimates. The vapor is condensed in
> the cold trap, which has to be cleaned from time to time. All the heat
> coming into your sample from the environment is used to increase the
> sublimation rate, the heat of evaporation ensures that the sample stays
> frozen until all solvent has been removed.
>
> In your case however, it perhaps would be more appropriate to extract the
> lipids and ship those. See
> @article{Rad-81,
>          AUTHOR= {M.S. Radin},
>          TITLE= {Extraction of tissue lipids with a solvent of low
> toxicity},
>          YEAR= {1981},
>          JOURNAL= {Meth. Enymol.},
>          PAGES= {5-7},
>          VOLUME= {72},
>          LANGUAGE= {engl}
> }
> which uses cyclohexane rather than chloroform as in
> @article{Bli-59,
>          AUTHOR= {E.G. Bligh and W.J. Dyer},
>          TITLE= {A rapid method for total lipid extraction and
> purification},
>          YEAR= {1959},
>          JOURNAL= {Canadian J. Biochem. Physiol.},
>          PAGES= {911-917},
>          VOLUME= {37},
>          NUMBER= {8},
>          LANGUAGE= {engl}
> }
> The trick with all these procedure is to work under nitrogen, to prevent
> lipid peroxidation.
>
>
> ------------------------------
>
> _______________________________________________
> Methods mailing list
> Methods from net.bio.net
> http://www.bio.net/biomail/listinfo/methods
>
> End of Methods Digest, Vol 54, Issue 14
> ***************************************
>




------------------------------------------------------------------------
This message was sent using IMP, the Webmail Program of Haifa University



More information about the Methods mailing list