This has only been a problem for me with very small samples, 0.3 mg or
less where the lid wasn't secured well.  What works well for us are to
run two pieces of lab tape perpendicular on the two long sides (tape
across A6 and H6).  Certain brands of trays may have tighter fitting
lids than others.

One could also cut out a mat out of a thin compressible material, like
what new electronics are sometimes wrapped in.

 
Benjamin Harlow
Manager, Stable Isotope Core Laboratory
Washington State University
School of Biological Sciences
G-81 Eastlick
Pullman, WA  99164-4236
 
Office:  509-335-6161
Lab:     509-335-6154
Fax:     509-335-3184
 
Laboratory for Biotechnology and Bioanalysis (LBB2) Stable Isotope Core
http://www.isotopes.wsu.edu
 
 
-----Original Message-----
From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On
Behalf Of greg michalski
Sent: Friday, November 14, 2008 8:10 AM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] Problems with receipt of pre-weighed samples

Caution if shipping samples  in the plastic centrifuge tubes, 
external pressure drops during air shipping can cause the tops to pop
off

At 11:01 AM 11/14/2008, Henkes, Gregory wrote:
>Mireille,
>
>We ship the often ship trays with a couple of layers of parafilm
between
>the plastic cover or a taped on piece of cardboard. No problems yet and
>we advise anyone sending samples to us do the same.
>
>Greg
>
>-----Original Message-----
>From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On
>Behalf Of David R. Vann
>Sent: Friday, November 14, 2008 10:57 AM
>To: [log in to unmask]
>Subject: Re: [ISOGEOCHEM] Problems with receipt of pre-weighed samples
>
>Mireille:
>
>My solution has been to cover the tray with aluminum foil, and press
the
>foil
>slightly into the wells, forming a concave depression. Cover this with
a
>piece
>of cardboard or tagboard and wrap it with a rubberband. The foil
indents
>'seal'
>and prevent the samples from bouncing out, and the cardboard keeps the
>foil from
>moving.
>
>
>DRVann
>
>Quoting Mireille Savoie <[log in to unmask]>:
>
> > Good day Isogeochemers,
> >
> > We are seeking the advice from others who may have experienced a
>similar
> > problem with
> > pre-weighed samples arriving by air mail.  We have received a few
>deliveries
> > of samples
> > weighed into the typical 96 well culture trays only to open the
trays
>and
> > find that the
> > samples have shifted out of their wells and into other wells.  The
>culture
> > trays are not
> > disposable and are made from very rigid material.
> >
> > Has anyone ever received trays in this state? If so, what do you
>recommend to
> > ensure that
> > this does not happen?
> >
> > Thank you in advance,
> >
> > Mireille
> >
> >
>
>
>David R. Vann, Ph.D.
>Forest Biogeochemistry and Physiology
>Department of Earth & Environmental Science
>The University of Pennsylvania
>240 S. 33rd St.
>Philadelphia, PA 19104-6316
>215-898-4906 FAX:215-898-0964

Greg Michalski, Assistant Professor
http://www.purdue.edu/eas/michalski/
Department of Earth and Atmospheric Sciences
Purdue University
550 Stadium Mall Dr.
Lafayette IN.47907