Friday, 12 February 2016

Absolute Integrals from TopSpin


I have a large number of samples which I have performed the same NMR experiments on.

One of the experiments (expno 12) produces a simple 1D 13C NMR spectrum with 2 peaks. 
These peaks are shifted ever so slightly between different spectra (due to concentration effects).

I can batch process them (phase, baseline), including peak picking, and defining an integration region mathematically that defines the same percentage of the lorentzian curve for both peaks.

However, I cannot get an output from TopSpin (automatically, batch process) which reports the absolute integrals of that spectrum. 

The integrals.txt file records only the relative integral, which is not useful to me (as I will be comparing a number of samples over a period of time and dont wish to have to re-integrate every sample every time). 

The mutli_integ au program looked promising, but is based on a series of expnos within the same sample file. I have the same expno across different samples. Additionally, it also only seems to report the relative integral (but relative across the set). 

The intser method also will not work as it redefines the intrng for each spectrum to be the same - which is not effective as my peaks shift.

Any ideas?

(TopSpin 3.2 pl7 and 3.5 pl4)

1 comment:

Chemist101 said...

Ok, the fact that there are not in the same sample but different ones makes it a bit tricky. I don't know an easy solution to that... The only thing that comes to mind would be to move all the expnos to the same folder and rename them (1,2,3...). But that is alot of work (Although less than manually integrating I would say).

For the integrals: Do you have any solvent peak in your 13C-NMR? If yes you could use it as a "standard" and just normalize your integrals to the solvent's integrals (in excel.

That's all I got sorry ;)