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I use a varian inova 500 NMR machine. it has vnmrj 2.1B software. An auto-x pfg 500 Mhz probe and auto tuning unit also. I need to do a 1H-31P hetcore experiment but I failed every time. I try to change default pulse sequenceS for 1H-13C HSQC or HMBC to 1H-31P nucleus but result is negative. what must I do for a successful 1H-31P Hsqc or Hmbc experiment?

asked Jul 27 '09 at 13:48

oksijen's gravatar image

oksijen
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updated Nov 18 '09 at 14:31

Evgeny%20Fadeev's gravatar image

Evgeny Fadeev
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You need to change the dn to P31, change the power and the 90 degree pulse to P31, too. Also change the delays or the couplings values to match those that are responsible for the coherence transfer. Also, as the previous answer point it out, change the power gradients to match the condition to refocuse the P31 magnetization if your pulse sequence requires it.

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answered Aug 07 '09 at 14:04

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Federico del Rio
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updated Aug 07 '09 at 14:04

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The gradients have to reflect the different gamma ratio P/H instead of C/H (or N/H).

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answered Nov 22 '09 at 14:53

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Kirk Marat
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You need to change the values of the gradients so that they reflect the fact that you are trying to "observe"31P as opposed to 13C

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answered Aug 07 '09 at 13:45

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Reed College
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updated Aug 07 '09 at 13:45

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Hello,

it is quite simple to do it. First look for the 1D of Phosphorous and Proton. Then you can switch the Proton experiment to a HMBC via the HMBC makro. Now you can set in the parameters from the 31P experiment to the 2D experiment. dn='13C' to '31P', dpwr and so on , j1h=140 to 5 Hertz, ...

we did not use the gradient edition of the pulse sequence, so we have not to fix the gradients

Have a nice experience.

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answered Apr 27 '10 at 00:34

Ulrich%20Haunz's gravatar image

Ulrich Haunz
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