Question: I am using LC-MS and the Cogent Diamond Hydride™ HPLC column. When analyzing quaternium-15, I see two peaks which have the same m/z. What can be the cause? Is there an issue of peak splitting?
Answer: Quaternium-15 can have either cis or trans orientation on the double bond. If you see two peaks in your data, it may not be from peak splitting but rather chromatographic separation of the two isomers.