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Gaussian peak fitting

Posted: Wed Feb 09, 2011 2:26 am
by mkawatasu
It would be nice if Clarity could have Gaussian peak fitting. This is our customer's request.

Internal issue tracking ID: 36122

Re: Gaussian peak fitting

Posted: Mon Feb 14, 2011 5:09 pm
by Daniel Mentlik
Dear Miyako,
we have already tried one deconvolution mechanism for these cases in the previous versions of Clarity, but rejected it because it gave insufficient results when used on more complex peak clusters over the course of the whole chromatogram. May I ask you how complex are your expected peak clusters?
Thank you for the answer,
Best Regards,
Daniel

Re: Gaussian peak fitting

Posted: Thu Mar 10, 2011 8:58 am
by mkawatasu
Hello,
I had the typical chromatogram sent by the user (see the attached file). The sample is low Mw synthesized compound. Two peaks are separated incompletely. The user would like to apply Gaussian fitting to it, and make the simple two peaks. He is using Origin software with Clarity. http://www.originlab.com/index.aspx?go= ... akAnalysis
TEST.JPG

Re: Gaussian peak fitting

Posted: Thu Mar 10, 2011 12:38 pm
by Daniel Mentlik
Dear Miyako,
the chromatogram you have showed us seems more like there are at least four unresolved peaks - the first "major" one has strange lumps both before and after its maximum. I'm afraid that the deconvolution procedure could create any result you wish from such peak cluster, based on the conditions you set to the procedure - it would just be a guessing from the crystal ball. Moreover, peaks generated from GPC are usually far from Gaussian shape, so I'm not sure any deconvolution would help in this type of analysis.
Please, could you send us the *.prm file or two with the mentioned peak cluster to support@dataapex.com for some testing?

Re: Gaussian peak fitting

Posted: Fri Mar 11, 2011 6:22 am
by mkawatasu
Dear Daniel,
Thank you for your reply.
I was conscious of several inflection point on the first peak. But this peak is one compound. In this case, ELSD is used as a detector, so peak shape is sometimes distorted. Actually, the peak is one peak.
I think the user would like to take Gaussian peaks simply created corresponding to "Local maximum" of chromatographic curve recognized as sample peaks.
I will send the prm file to you by e-mail.