Huge peak tailing on MS but not UV

This is something I have observed with different samples and across multiple models of instruments that's always bothered me. Essentially my analyte will have a sharp UV peak, but the EIC/TIC will have a huge amount of tailing in a very characteristic double hump shape. The LC gradient also does not have an effect on the peak shape. I've attached a picture illustrating this phenemenon. 

Does anyone have any idea what is causing this? All of the common explanations like dead volume etc. don't seem to apply, since I've observed this on multiple machines, and the back hump is still the same analyte (i.e. exact same charge envelope). For reference these are intact protein samples.

  • TIC contains too many ions that UV can't detect normally,  i recommend to select your interested ion and extract it with EIC or inject it individually using SIM,  mostly you will not find any tailing

    if thev tailing still exists then it maybe ( solvent effect or high concentration effect)

    then you can try a smaller injection volume or dilute your sample with ( mobilephase like) solvent

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