Hello All, anyone having experience working on NDSRIs of Duloxetine impurities like Nitroso Duloxetine Imp A, Nitroso Duloxetine Imp B, Nitroso Duloxetine Imp C, Nitroso Duloxetine Imp E and Nitroso Duloxetine Imp F.
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Hello!
Can you be a little more specific about your problem so we can try to help you, perhaps through brainstorming?
Is your problem with methodology? Acceptable intake?
There is a topic by @Yosukemino about N-nitroso-duloxetine methodology: Simple and Practical Method for the Quantitative High-Sensitivity Analysis of N-Nitroso Duloxetine in Duloxetine Drug Products Utilizing LC-MS/MS
Hi, my name is Da-Kong, I am working on determining N-nitroso duloxetine (NDXT) in API with LCMSMS. I find different quantitation MRMs of NDXT were used in different references such as 344 (M+NH4)+ > 183, 183 (?) > 123 and 327 (M+H)+ > 183 . It could be affected by different mobile phase composition w/wo ammonium ion. Interestingly, we also find m/z 183 is the most abundant Q1 mass without the presence of ammonium ion. That is the same as what in the swissmedic’s mehtod and USP Product Information Sheet of N-Nitroso Duloxetine Solution. However, I have no idea how m/z 183 is produced. Is it reasonable from NDXT’s chemical structure? Should I use m/z 183 as the parent ion?