Hi,
the buffer concentration surely will play a major role here (leading to said
Q-spoiling), so it would be very important to have an idea which buffer
concentrations they are expecting or what their lowermost limit could be. I
remember cryoprobes can suffer badly to the extent that they have the same
S/N as an RT probe at very high salt concentration.
You can partially overcome this by using these (expensive) shaped NMR tubes
which avoid the electric field generated by the RF coil, but that will be
much larger with a 8-10 mm coil (not sure whether shaped tubes are available
for 8-10 mm - never seen these).
Does a 10 mm cryoprobe with PFG exist at all? 10 mm probes with PFG are already
not easy to achieve in RT probes (space requirement), adding the dewar will be
extremely challenging.
Cheers
Bert
> Am 28.10.2024 um 19:34 schrieb Charles Fry <cfry03_at_esf.edu>:
>
> Hi all,
>
> I’m supporting a protein research group that needs to work at low
> concentrations (20-50 uM) and is asking about using a 10mm cryoprobe. I’ve
> talked about line shape and shimming on such probes, and also mentioned
> 8mm probes. I’m uncertain about how bad Q-spoiling by buffers might be.
> I’ve used X-direct-detect 10mm probes, but have only talked with vendors
> about 8mm probes and those discussions were at least 10 yrs ago. What I recall
> is that 5mm probes are better optimized for both line shape and sensitivity, and
> that overcomes (at least most of) the advantages of larger sampling volume with
> the bigger diameter probes. But I’ve always wondered how much the economics of
> such expensive devices -- a larger diameter probe having considerably narrower utility
> -- might influence such discussions. One aspect is whether new shimming technologies
> might make the larger diameter probes more competitive than they used to be?
>
> The research group remains interested in the possibilities. I agreed to ask in this
> forum who might have such probes, especially those that would be open to outside
> academic use. Even if you have a probe that is not available for use to others, it
> would be great to hear more about their utility for 1H- and 13C-detected 2D and 3D experiments.
>
> Cheers,
> Charlie
>
>
>
Magnetic resonance equipment, service, training & more
Selling & buying used NMR equipment (all vendors)
Dr. rer. nat. Bert Heise
Owner, Applications Scientist
Spin-Doc Bert Heise
Kiefernweg 13
58239 Schwerte
Germany
Mobile: +49 171 5135315
Email: bert.heise_at_spin-doc.net
Web: http://www.spin-doc.net
Representing:
Stelar Fast Field Cycling NMR Relaxometers (
http://www.stelar.it)
MestreLab NMR Software (
http://www.mestrelab.com)
Barthel HF Amplifiers (
http://www.barthel-hf.de)
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#1797): https://urldefense.com/v3/__https://ammrl.groups=
.io/g/main/message/1797__;!!PvDODwlR4mBZyAb0!UFUP_8-otHtSFAjfqDfJfIHuMiHsA5=
eFlxKh0VdMDCLM9sWEEjE7I26xdAEhdiiBwGqwOmzsSGggpsRBWyxN2g$
Mute This Topic: https://urldefense.com/v3/__https://groups.io/mt/109263554=
/7559972__;!!PvDODwlR4mBZyAb0!UFUP_8-otHtSFAjfqDfJfIHuMiHsA5eFlxKh0VdMDCLM9=
sWEEjE7I26xdAEhdiiBwGqwOmzsSGggpsQfG4lNyg$
Group Owner: main+owner_at_ammrl.groups.io
-=-=-=-=-=-=-=-=-=-=-=-
Received on Tue Oct 29 2024 - 03:33:28 MST