Axel,
Labco made a new thread profile for one of their 12mL round bottom exetainers (RK in part #). On their website they say, "The new thread profile on this Exetainer® gives a very tight screw fit, and is designed to avoid any cap movement when samples are heated - e.g. on a Gas Bench".
Replacement caps are the same for all the 16.5mm exetainers, round bottom, flat bottom, 3mL to 12mL. You can get them in all colors of the rainbow.
One thing of importance is that just being flat bottomed or round bottomed does not determine the vial material. It is possible to get untreated soda glass or borosilicate glass in flat or round bottom vials.
For highest purity applications and ability to bake vials, the folks at Labco recommended the borosilicate vials.
Also double check what came with your instrument. Our gas bench was shipped 14mL (yes 14mL!) round bottom silicone coated vials that were custom made for a breath test company in Europe. I did not discover this until I sent a batch number inquiry to Labco. They were labeled as 12mL standard soda glass and sent with a carbonate application start up kit. I brought this to the attention of Thermo and they immediately sent me the highest quality borosilicate vials.
More info to match your spares here: http://www.labco.co.uk/usaandcanada/index.htm
Regards,
Ben
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 Gilles St-Jean
Sent: Friday, July 17, 2009 8:06 AM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] Exetainer vials-Caps thread mismatch
Hi Axel
The tread mismatch is deliberate by Labco. The vials and caps are not the same and one of them, usually the flat bottom one, has an invisible coating on the inside, which may affect isotopic results on some samples.
The coating is there for breath sample analysis (breath = 5% CO2). They are meant to show moisture by "fogging" up and staying fogged up after the vial is closed whereas the other vial (e.g. round bottom) are just straight Pyrex. This gives the operator a quick visual on used vials.
You can tell the difference by blowing through a straw inside each type and capping them immediately. Both will fog up but the flat bottom vial will stay fogged whereas the other one will return to transparency.
Regards
Gilles
Gilles St-Jean
Chercheur / Research Scientist
Université d'Ottawa / University of Ottawa
Sciences de la Terre / Earth Sciences
Laboratoire d' isotopes stables- G.G. Hatch- Stable Isotope Laboratory
140 Louis Pasteur, RM 101
Ottawa, Ontario, Canada K1N 6N5
Tel: 1-613-562-5800 xt 6830 (Bureau / Office)
xt 6839 (Bureau / Office Lab)
xt 6836 (IRMS lab)
Téléc. / Fax: 1-613-562-5192
Courriel / E-mail: [log in to unmask]
Toile / Web: www.isotope.uottawa.ca
"You can please some of the people all of the time, and all of the people some of the time, but you can not please all of the people all of the time".
Mod. from Abraham Lincoln (attributed); 16th US president (1809 - 1865)
> -----Message d'origine-----
> De : Stable Isotope Geochemistry [mailto:[log in to unmask]] De la
> part de Axel Rosas
> Envoyé : 30 juin 2009 20:11
> À : [log in to unmask]
> Objet : [ISOGEOCHEM] Exetainer vials-Caps thread mismatch
>
> Hello everyone,
>
> I got a set of flat bottom vials with caps (labco) and a set of round
> bottom
> vials (kymex?) without caps with my Delta Plus Adv. + GB. The caps match
> the flat bottom vial perfect, but putting them on the round bottom vials
> is
> a real pain. It actually leaves my fingers sore for a while. Has anyone
> found non Labco round bottom vials that match the Labco (blue) caps. I
> havent been able to find the thread number for the Labco caps.
>
> Best regards to all,
>
> Axel
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