Hydrogel molecularly imprinted polymer-based electrochemical sensor on gold-modified screen-printed carbon electrodes...

Glycated hemoglobin (HbA1c) is a key biomarker for long-term glycemic control and diabetes diagnosis. Common methods such as chromatography and immunoassays are accurate but require costly instrumentation, limiting their use in point-of-care settings. Electrochemical sensors offer a portable and sensitive alternative. This study integrates computational modeling with hydrogel-based molecularly imprinted polymer (MIP) engineering to achieve selective HbA1c recognition. Molecular docking coupled with molecular dynamics simulations guided the rational design, identifying optimal binding sites and confirming the structural stability of the monomer-template complex. A hydrogel MIP sensor was fabricated on a gold-modified screen-printed carbon electrode using 2-acrylamido-2-methyl-1-propanesulfonic acid as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. Successful polymer formation and template removal were confirmed by FTIR and XPS, while SEM verified uniform deposition of gold particles and MIP layers. Electrochemical characterization was performed using K₃[Fe(CN)₆]as the redox probe. The developed SPCE/Au/MIPs sensor exhibited a wide linear range 10-10⁵ ng/mL and LOD 1.13 ng/mL. A strong imprinting factor (IF 4.96) and high selectivity (98.7 %) confirmed effective molecular recognition, while long-term stability was demonstrated by stable performance over 120 days at room temperature with 94 % signal retention. Real sample measurements showed 95-112 % recovery compared to NGSP-standardized HPLC, with good reproducibility, validating its practical applicability. Overall, hydrogel MIP platform provides a robust, sensitive, and durable approach for HbA1c monitoring, supporting good health and well-being through accessible diabetes diagnostics.