Highly sensitive galectin-3 electrochemical sensor based on a dual-recognition interface of cyclodextrin-integrated molecularly imprinted polymers (MIPs) and an aptamer.

Heart failure (HF) is a major global health burden, and elevated serum levels of galectin-3 (Gal3) are widely recognized as a reliable biomarker of disease progression. Accurate detection of Gal3 is vital for prognosis and effective management of HF. This study develops a dual-recognition sandwich sensor for Gal3, providing a sensitive and selective platform for quantitative biomarker analysis. By accurately measuring Gal3 levels, this system can effectively evaluate the severity of HF and track changes over time and in response to treatment. The integration of dual-recognition elements enhances analytical reliability, reinforcing its potential applicability in clinical HF management. The sensor employs a hexakis-(6-mercapto-6-deoxy)-β-cyclodextrin (mCD)-integrated polypyrrole (PPy) as a molecularly imprinted polymer (MIP), referred to as "mCD/PPy MIP". This design promotes the oriented immobilization of the Gal3 template via self-assembly during MIP fabrication. In parallel, a Gal3 aptamer, identified through molecular docking analysis, is conjugated to copper phosphate encapsulated within amine-functionalized silica nanoparticles (Cu-labeled NPs), which functions as an electrochemical signaling probe. Under optimal conditions, the sensor exhibited a linear detection range of 0.1-80 ng mL-1, with a limit of detection (LOD) of 0.1 ng mL-1 and a limit of quantification (LOQ) of 4.5 ng mL-1. This performance is sufficient to support clinical prognosis assessment and risk stratification in HF. The sensor demonstrated high accuracy and precision, with no interference, while effectively detecting Gal3 in human serum albumin (HSA)-depleted, lipid-free serum samples, showcasing its potential for HF prognosis and monitoring.