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Updated: Nov 20, 2025

Chemically-blocked Antibody Microarray for Multiplexed High-throughput Profiling of Specific Protein Glycosylation in Complex Samples
Published on: May 4, 2012
Potentiometric Determination of Circulating Glycoproteins by Boronic Acid End-Functionalized Poly(ethylene
Akira Matsumoto1,2, Shigehito Osawa3, Takahiro Arai1
1Institute of Biomaterials and Engineering, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyada-ku, Tokyo 101-0062, Japan.
Abstract:
Despite tremendous complexity in glycan structure, sialic acid (SA) provides an analytically accessible index for glycosylation, owing to its uniquely anionic nature and glycan-chain terminal occupation. Taking advantage of boronic acid (BA) based SA-recognition chemistry, we here demonstrate a label-free, no enzymatic, potentiometric determination of fetuin, a blood-circulating glycoprotein implicated in physiological and various pathological states. A phenylboronic acid (PBA) ω-end-functionalized poly(ethylene glycol) (PEG) with an α-tethering unit bearing pendent alkyne groups was "grafted-to" a gold electrode modified with 11-azide-undecathiol by a copper-catalyzed azide-alkyne cycloaddition reaction. Using the electrode, fetuin was potentiometrically detectable with a μM-order-sensitivity that is comparable to what is found in blood-collected specimen. Our finding may have implications for developing a remarkably economic hemodiagnostic technology with ease of downsizing and mass production.
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