Gangliosides and Incorrect Charge Status March 12, 2021, 05:39:19 AM Dear DevelopersI am working on a lipidomics study of cancer patients plasma. Before starting with the untargeted acquisition, I did some tests on lipid standards and I found that on a particularly large ganglioside (over 1600 Da) MSDIAL can not recognize the bicaric state of the molecule, even if it is markedly evident, and then it tries a misidentification as if it were M- and not M2-. I don't understand the reason. I can safely share the raw files as the MSDIAL session.all the best Andrea
Re: Gangliosides and Incorrect Charge Status Reply #1 – March 13, 2021, 08:19:48 AM Hi, this is because the current MS-DIAL does not have the MS/MS spectra of GM3 [M-2H]2-.As long as I checked your ppt, MS-DIAL recognizes the ion as double charge. However, since there is no spectral information for the GM3 double charged ion, the annotation is wrong. We will make the library for these ions as soon as possible. Please wait.Thanks,Hiroshi
Re: Gangliosides and Incorrect Charge Status Reply #2 – March 13, 2021, 02:33:42 PM Dear Hiroshithanks for the quick reply.It would actually be GD2. Given the importance in the clinic of this marker, as in the diagnosis of Neuroblastoma, would it be possible to include this class of lipids as well? HMDB reports almost 30 of them and only one is verified to be present in plasma, which in my opinion should be further investigated, as well as some acetylated or modified lipids. I think GD1 and GD3 might also be of considerable interest.Is there any possibility of these integrations?all the best Andrea
Re: Gangliosides and Incorrect Charge Status Reply #3 – March 15, 2021, 06:51:41 PM Hi Andrea,we have already analyzed the standards by LC-MS/MS one year ago, but I had no time to implement these (I forgot them..). In this month, since I have much time to do source coding, we will address the implementation for the lipid classes! Maybe, within this week.Hiroshi
Re: Gangliosides and Incorrect Charge Status Reply #4 – March 21, 2021, 07:19:39 PM Dear Andrea,please let me know your e-mail address. I will send the msdial program supporting these gangliosides to you privately first.Thanks,Hiroshi
Re: Gangliosides and Incorrect Charge Status Reply #5 – March 23, 2021, 03:51:01 AM clinical.proteomics.metabolomics@gmail.comthanks!Andrea