QA-QC Protocols and Spectra

Introduction

This page contains spectra that are representative of the normal level of performance of this instrument.  A brief description of the acquisition protocol is given for each set of measurements.  More detailed information about the proper instrument set-up and operational parameters necessary to reproduce these measurements can be found in the appropriate training manual or application note. 

NMR Specification Tests

Typically, the two parameters of concern in NMR are resolution/lineshape and sensitivity. This page contains information regarding the specifications for the DRX 400. It also contains a recent set of lineshape and sensitivity spectra for 1H and 13C for reference. Additional nuclei can be tested upon request. We ask that any time you have a question about lineshape or sensitivity, you first run one of the test protocols listed below in order to ensure that the issue is not related to your sample. Once the issue has been identified, additional troubleshooting of sensitivity and/or lineshape can proceed.

Resolution/Lineshape Test Protocol:

  1. Insert the 3% CHCl3 in acetone-d6 sample. For measuring 13C lineshape, use the 40% Dioxane in Benzene-D6 sample.
  2. Perform LOCK, and topshim as directed in the AVIII-600 User Guide. 
  3. Load a standard proton experiment as directed in the user guide. Change ns=1, td=80k (80*1024). Type aq<enter> and a pop-up box should return aq=6.24. This parameter change is to ensure adequate acquisition time (aq) in order to eliminate truncation and obtain the full resolution of the peak. Also type si<enter> and make sure si=80k.
  4. Type rga<enter> and wait for it to finish, and then type zg<enter> to start the acquisition. 
  5. When the experiment has finished acuiring, zoom in a region surrounding the chloroform peak and type pps<enter> (will pick peaks) and humpcal<enter>. A window containing the linewidth values for 50%/0.5%/0.1% will pop up on the screen. 
  6. If the lineshape is significantly broader than spec (e.g. 50% > 1.0 Hz), continue optimizing the shims, possibly optimizing Z3, Z4 and other higher order shims and re-acquire the spectrum (simply typing zg<enter> again will overwrite the previous data). It may also be possible that a new 3D shimmap will need to be acquired (requires staff assistance). 
  7. If you can't get the lineshape to a reasonable value, send us an email containing the results of the lineshape test and we will re-shim the probe as soon as we are able. If the lineshape test meets spec but your particular sample has very broad lines, it is possible that something is wrong with your sample, the instrument cannot shim your sample well, etc. 

Typical AVIII-600 1H Lineshape: 50%/0.5%/0.1% = 0.5 Hz/8 Hz/14 Hz

 

 

Probe: PA BBO 600S3 BBF-H-D-05 Z SP (BBFO Probe)

Pulse Specification

Nucleus Sample 90° Pulse (in us) Achieved Power (in W) Maximum allowed peak power (in W)
1H 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 11 22 120
13C 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 12 109 160
15N 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 18 186 260
19F 0.05 Trifluorotoluene in Chloroform-D 14 32 50
31P 0.0485 M Triphenylphosphate in Acetone-D6 12 53 70

 

Sensitivity

Nucleus Sample Signal-to-Noise Remarks
1H 0.1% Ethylbenzene (EB) in Chloroform-D 875 noise: 200 Hz variable, method: sino best
13C 40% Dioxane in Benzene-D6 330 noise: 40 ppm variable, method: sino best
13C 10% Ethylbenzene (EB) in Chloroform-D 330 noise: 40 ppm variable, method: sino best, with 1H dec during acquisition
15N 90% Formamide in DMSO-D6 45 noise: 2ppm variable, method: sino best, with 1H dec during acquisition
19F 0.05 Trifluorotoluene in Chloroform-D 700 LB: 0.5 Hz, noise: 1ppm variable, method: sino best, with 1H dec during acquisition 
31P 0.0485 M Triphenylphosphate in Acetone-D6 250 noise: 5 ppm variable, method: sino best

 

Lineshape

Nucleus Sample 50% (in Hz) 0.55% (in Hz) 0.11% (in Hz) Remarks
1H 1% Chloroform in Acetone-D6 0.80 7.0 14.0 without rotation
13C 40% Dioxane in Benzene-D6 0.20 3.0 5.0 with rotation & 1H dec

 

 

Probe: PH TBI 600S3 H/C-BB-D-05 Z (TBI Probe)

Pulse Specification

Nucleus Sample 90° Pulse (in us) Achieved Power (in W) Maximum allowed peak power (in W)
1H 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 10 9.2 20
13C 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 20 189 300
13C(BB) 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 15 110 150
15N 100 mM Urea-15N + 100mM MeOH-13C in DMSO-D6 30 100 160
31P 0.0485 M Triphenylphosphate in Acetone-D6 25 76 120

 

Sensitivity

Nucleus Sample Signal-to-Noise Remarks
1H 0.1% Ethylbenzene (EB) in Chloroform-D 850 noise: 200 Hz variable, method: sino best

 

Lineshape

Nucleus Sample 50% (in Hz) 0.55% (in Hz) 0.11% (in Hz) Remarks
1H 1% Chloroform in Acetone-D6 0.45 5.0 10.0 with rotation
1H 1% Chloroform in Acetone-D6 0.70 6.0 12.0 without rotation