A new approach to sensitively analyze glycoprotein with MUC1 as an example for the diagnosis of ovarian cancer

Glycoproteins require sensitive detection for both biomedical research and clinical examination. Although existing strategies exploit glycosylation sites for recognition or signal labeling, they have not taken full advantage of glycoproteins’ potential as natural signal amplification platforms. To overcome the limitation, this study proposes a highly sensitive and modification-free electrochemical detecting strategy. Which employs a boronate derivative featuring dual-boronic acid groups. Through boronic acid-cis-diol specific interactions, the derivative simultaneously and directly co-immobilizes target glycoproteins and glycan-modified cascade enzymes via covalent polymerization. This forms an enzyme cascade amplification network, inducing methylene blue (MB) redox cycling to generate a differential pulse voltammetry (DPV) signal output. Using mucin 1 (MUC1) as a model target, the constructed biosensor achieves a detection limit of 116 fM with a wide linear range (0.2 pM-20 nM), meeting clinical requirements for glycoprotein quantification. The method also delivers promising results for MUC1 detection in clinical serum samples. Collectively, this work fully leverages the intrinsic potential of natural glycosylation sites on glycoproteins. The innovative dual-boronic acid “molecular grasper” strategy enables efficient and specific signal amplification, offering advantages including operational simplicity, cost-effectiveness, and rapid response. Ultimately, it provides a novel pathway for developing universal glycoprotein detection platforms, demonstrating significant value for disease diagnosis and biological research applications.