DPX 400 – Probe Change

Various users have requested a change in capabilities on the DPX 400 MHz (NMR-Paprika) in Evans 0083. The probe which has been installed since 2011 was an inverse probe (BBI) – optimized for 1H detection and 2D experiments. However, this probe was not useful for acquiring quality 13C spectra or other nuclei.

The probe installed today is a QNP probe (quartenary nuclei probe) capable of acquiring NMR spectra from four nuclei: 1H, 13C, 31P, 19F.

What you need to know:

  • Shim  file: To load a shim file prior to shimming the probe, type QNP.shim
  • Default tuning: The probe is currently tuned to 1H and 13C. The 1H tune is not as sensitive to solvent changes, such that tuning the proton channel is not necessary for standard 1H experiments. If you’d like to learn to tune the probe (wobb) for quantitative 1H or 2D experiments, please let me know. The procedure is a bit different than the BBI probe.
  • 31P and 19F: If you need to acquire these nuclei please contact me for training. The procedure for tuning is very different from the BBI probe.

Let me know if you run into any problems!!

AVIII 400 Status: AVAILABLE

The AVIII 400 NMR-Saffron is down due to a hardware failure.  Because there is a chance of sample breakage – the system will be unavailable until the issue is resolved.  Please plan on the system being down for a few days.  The 400 MHz in Evans is available (quick walk in the cold weather) or have a labmate run samples on the 600 MHz.

Problem details:  The SampleJet ‘arm’ falls after the sample is inserted.  When the sample is ejected, the NMR tube gets pushed down into the spinner.  At this point, the system fails to pick up the sample and stops the run.  So far, this has not broken an NMR tube, but it perhaps might.  Bruker has been contacted to determine the source of the problem.

Update 1.5.2018:  The system is now available.

AVIII 400 MHz – Probe Repair Date

PROBE REPAIR:  AUGUST 14

The probe will be sent to Bruker’s shop on Monday, August 14th. The system will likely be unavailable during this repair. Turnaround from Bruker probe repairs range from 1-3 weeks. They have be notified of the critical nature of this automated system and will attempt to return the probe to us quickly and/or provide us with a back-up probe.

Thanks for your patience with this hardware issue, and thanks for being more careful with sample handling. The last time this probe needed to be sent to Bruker’s shop was in 2012, so let’s try for another long run without major issues!


Email from 7.14.2017

As most of you are aware – we’ve been seeing peak doubling on the AVII 400 MHz for all X-nuclei experiments (13C, 19F, 31P, 11B, etc.).  Data for the 13C CDCl3 peak isbelow. The peaks show up 20 Hz downfield of the original peak(s).  Proton experiments are completely ok!

The problem seems like to originate from the probe.  You may recall that a few months ago, we had at least one sample break inside the probe.  This caused breakage of the probe insert – plus, the RF coils were bent out of alignment.  Although we were able to get back to a working state – it is most likely that the problem has returned.  We’ll take a look at the probe locally in the next few working days, but the probe will likely need to be sent to Bruker for repair.  Bruker usually does not have a back-up ATM probe to provide, but they are checking to see if this is possible.  I’ll continue to update all the NMR users as I learn the plan moving forward.

In the meantime… another reminder….

**Make sure all NMR caps are FULLY on the NMR tubes**

If the caps are not completely pushed onto the NMR tube, the sample is too long and can break in the probe.  When I checked the rack even this week – I’m finding several tubes that are hanging too long and are caps not properly placed.  Also, don’t use caps that have split. I’ll be contacting users about this in the future – and giving stern warnings and/or remove access to the instrument. Please follow the procedures as trained so that the instrumentation will continue to provide quality data without hardware issues!  Attached is Norrell’s directions for properly placing a cap on an NMR tube for the SampleJet.  I have several Norrell NMR tubes with these marks and would be happy to show anyone who is interested.

**Use only pristine NMR tubes**

Do not use NMR tubes that have been cracked at the top.  The NMR cap cannot be properly seated on a damaged tube.  If we find NMR tubes that are too short – they will be pulled from the system.  Also, be sure the outside of your NMR tube is completely clean!  Start by cleaning your tube thoroughly in your lab.  Use a Kimwipe to clean the NMR tube further before placing it in the magnet.

TOPSPIN LICENSE UPDATE

The free license for Topspin 3.5pl6 has expired as of March 31, 2017.  If you are using the departmental license file, you will not notice this expiration.  However, if you are using the free Topspin option, you will need to download and install the latest version – Topspin 3.5pl7.  Let me know if you have any questions or problems with this installation.

https://www.theresonance.com/free-academic-version-topspin/

Topspin 4.0 was announced at the ENC as well as their newest console design Avance NEO.  The processing version of Topspin 4.0 will be available soon for download.  This new version is not compatible with our AVIII consoles.

 

Problem with AVIII 400 *resolved*

The AVIII 400 MHz (in CBEC) is experiencing an occasional error. The instrument will fail to complete an ‘ATM’ or ‘rga’ during the experiments and the instrument then sits until we reboot. This appears to be a hardware problem in the console. I’m in communication with Bruker to pinpoint the issue and make repairs as quickly as possible. In the meantime, we’ll be checking the system as much as possible to keep the queue moving along. If the system has a failure on your sample, you will need to resubmit.

Thanks for your patience as we troubleshoot the problem.

UPDATE 7.5.2017

Topspin 3.5pl7 is currently being installed on the system to alleviate these intermittent atma issues.  Please be patient as there are a few issues with the upgrade.  Hopefully, the system will be back up and running today or tomorrow!!  Very sorry about this interruption!!

UPDATE 7.7.2017

Great news – the software upgrade has been completed successfully! Thanks so much for your patience having the system down for 1.5 days! Please keep me informed if you run into any problem – no matter how insignificant it seems. I’ll be monitoring the system carefully.

Continue to be diligent with sample handling:
No damaged/split caps
No damaged/chipped NMR tubes
Caps must be on completely
Double-check that your sample position # isn’t currently being used

Hopefully, we’ll have less issues from both software glitches and user error. We’d all like to less downtime on our workhorse NMR instrument!