Glutathione-Functionalized
Magnetic Covalent Organic
Framework Microspheres with Size Exclusion for Endogenous Glycopeptide
Recognition in Human Saliva
posted on 2019-12-03, 23:43authored byBin Luo, Jia He, Zhiyu Li, Fang Lan, Yao Wu
Endogenous glycopeptides have been confirmed to play
a significant
role in multifarious pathological and physiological processes. The
low abundance of endogenous glycopeptides and abundant interferents
(e.g., large-size proteins and heteropeptides) in complex biological
matrices render the direct analysis of endogenous glycopeptides difficult.
Reported here is a novel glutathione-functionalized magnetic covalent
organic framework microsphere (denoted as MCNC@COF@GSH) endowed with
size-exclusion effect and strong hydrophilicity for selective and
efficient enrichment of N-linked glycopeptides. The as-prepared MCNC@COF@GSH
microspheres possessed fast magnetic responsiveness, regular porosity,
large surface areas, and good hydrophilicity, resulting in remarkable
performances in N-linked glycopeptide enrichment with low detection
limit (0.01 fmol μL–1), high selectivity (1:5000,
human immunoglobulin G (IgG) digests to bovine serum albumin digests),
excellent size-exclusion effect (IgG digests/IgG/bovine serum albumin
(BSA), 1:500:500), and reusability (at least five times). More excitingly,
143 endogenous N-linked glycopeptides were clearly identified from
10 μL sample of human saliva treated with the MCNC@COF@GSH microspheres,
which is the unprecedented high efficiency in endogenous N-linked
glycopeptide enrichment from human saliva. In addition to providing
a strategy for versatile functionalization of magnetic covalent organic
frameworks (COFs), this study may be used to develop application of
endogenous glycoproteome analysis.