Glycan‑Selective Signal Boosting in MALDI‑MS Enabled by Conductive Adhesive Supports

<jats:p>Glycan profiling by MALDI mass spectrometry is a high-throughput approach for characterizing biological samples, revealing shifts in glycan structures that reflect biological function, cellular communication, and disease‑associated alterations. Over the years, numerous analytical strategies—such as MALDI matrix optimization and chemical derivatization—have been developed to improve the yield and sensitivity of glycan detection. Here, we report an unexpected finding: spotting glycan arrays onto copper or carbon adhesive tape enhances glycan signal intensity by an order of magnitude compared with the most commonly used MALDI targets for glycan analysis. Through a series of experiments, including sputtering various metals, we determined that this enhancement arises from the adhesive or filler material in the tape rather than from the metal coating itself. We further demonstrated that this effect is glycan-specific, as no comparable enhancement was observed for metabolites, lipids, or peptides. The importance of direct glycan–adhesive interaction was underscored in N‑glycan tissue imaging experiments, where the tissue imposes a physical barrier that limits the boosting effect. Collectively, these results introduce a simple, inexpensive, and effective strategy for glycan enrichment and for detecting very low-abundance glycans that would otherwise go undetected.</jats:p>