500 MHz NMR checklist

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Revision as of 05:03, 13 October 2012 by Bozhang (talk | contribs)

Check in

Make sure the system is accessible, e.g. not being used or under maintenance

Check the status of the cryoprobe shown on the laptop screen

Check your belongings on your body and remove anything with ferromagnetic properties such as electronic devices and keep them away from the probe

Login

Load your sample(s)

Start topspin software

Type in “rsp” to save the last dataset

Type in “rsh” (use the newest cryoprobe shim set of your specific solvent)

Type in “lock” and when finished, push the button standby Shim Z1, Z2 manually

Type in “gradshim” (use the proper gradshim settings for a heavily protonated or deuterated solvent)

Wait for it to finish and evaluate the results, if they are not good repeat gradshim

Close gradshim

Make sure the lock light is on Type in “atma” to tune and match the probe Find the proton 90 time (“p1”)

Be sure to use zg and not zg30 Update p1

Note: The command “edprosol” opens the field values 1H pulsewidth then power to change proton 90 degree pulse (for example getprosol 1H 8.3 2 will set the proton 90 time to 8.3 µsec at a power level of 2 dB for your current TOPSPIN session only. Each value is separated by a blank space).

Choose the solvent

Type in “rgacryo” Start running

If you use the BACS automation:

a) Store the necessary gradshim file for automation, understand that ICON willlook for the shim file under a specific name

b) Use administrative password to change default p1

c) Type in “getprosol” to update the parameters

d) Set up the parameters for your first sample in “icon” program

e) Change au_zg to zgonly if you need constant rg value

f) Make sure the sample is not rotating: Go to configuration and click master switches, check the box next to never rotate sample note the selections on the other switches that are important like the lock selections and the standard shim file loading selection. You must be logged in as “nmrsu” (nmr superuser) to change this.

During the running

Pay attention to the weather conditions especially any electric outage. Follow the “cryo platform outage procedure” as being described by Joe.

Check out/end of run

If any samples are reloaded into the belt, verify that the sample tube is not set to the wrong depth (spinner tightness)

Load the reference CDCl3 sample

Type in “rfshim” and choose the newest CDCl3 cryoprobe shim set

Type in “lock CDCl3” Type in “atma” Change p1 back to the pulse length listed in the back of the log book by the computer

Eject the sample and remove the NMR tube from the spinner Leave the spinner in the black holder at the workstation

Sign up the log book and clear up the area

If you use the BACS automation: First thing is to: Stop the running (when all samples are finished)

Type in “edprosol” and change p1 value back (same procedure above)

Note

1. Make sure your tube is clean, the spinner is clean, the sample is 600 µL and the tube is in the right depth of the spinner, holding tightly. If you have multiple samples, they need to have the same volume and fit into the spinners at the same height.

2. Use a container or a rack to carry the NMR tubes from your own lab to the NMR lab. Make sure the sample is not reactive with the solvents and uniformly dissolved in your solvent.