Accurate Quantification of N‑Glycolylneuraminic Acid in Therapeutic Proteins Using Supramolecular Mass Spectrometry
journal contributionposted on 28.08.2018 by Hyun Hee L. Lee, Chae Eun Heo, Nari Seo, Seung Gyu Yun, Hyun Joo An, Hugh I. Kim
Any type of content formally published in an academic journal, usually following a peer-review process.
Practical applications of innovative host–guest systems are challenging because of unexpected guest competitors and/or subtle environmental differences. Herein, a supramolecular mass spectrometry (MS)-based method using a synthetic host, cucurbituril (CB), was developed for identifying and quantifying N-glycolylneuraminic acid (Neu5Gc) in therapeutic glycoproteins, which critically reduces drug efficacy. The development of a reliable derivatization-free analytical method for Neu5Gc is highly challenging because of the interference by the abundant N-acetylneuraminic acid (Neu5Ac). CB recognized the subtle structural differences between Neu5Gc and Neu5Ac. Distinct host–guest interactions between CB and the two sialic acids produced a highly linear relationship between the complexation and concentration proportions of the two sialic acids in MS. Furthermore, the developed method had sub-picomolar quantification limits and a wide range of applicability for diverse glycoproteins, demonstrating the potential utility of this method as a reliable assay of Neu5Gc in therapeutic glycoproteins.