An electrochemical immunosensor for adiponectin based on one-step immobilization strategy using gold-sputtered silver screen-printed electrode and sulfhydrylated antibody
摘要
Adiponectin serves as a critical biomarker for metabolic disorders, with its concentration in human plasma providing predictive value for the risk of prediabetes. In this work, we report a rapid and reliable electrochemical immunosensor designed for point-of-care testing of adiponectin. The immunosensor was fabricated using a gold-sputtered silver screen-printed electrode as the substrate, on which sulfhydrylated antibodies were directly immobilized via Au-S covalent bonding. The fabrication process was characterized and optimized using electrochemical impedance spectroscopy and differential pulse voltammetry. Under optimal conditions, the proposed immunosensor exhibited a wide linear range (0.3–15 μg/mL) with a detection limit of 0.15 μg/mL. It also demonstrated excellent reproducibility and high selectivity for adiponectin detection. Additionally, the proposed immunosensor can be fabricated within 1.5 h and enables accurate quantification in human plasma within 15 min. The practical applicability of the sensor was validated through analysis of human plasma samples, and the comparison results with commercial ELISA kit are satisfactory.
Graphical abstract