小中大glycan variations为什么是碱性峰？我理解glycan variations是由马来酸之类的造成的adduct formation,应该是酸性峰。难道是两个概念？
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同意楼上的，确实glycation会使得IEC变的偏acidic。
"Glycated lysine residues no longer carry a positive charge, and a net acidic change was observable"
来自“A study in glycation of a therapeutic recombinant humanized monoclonal antibody: Where it is, how it got there, and how it affects charge-based behavior”.
