Electrochemiluminescence paper-based screen-printed electrode for HbA1c detection using two-dimensional zirconium metal-organic framework/Fe

Glycated hemoglobin (HbA1c) is one of the most popular biomarkers which can be utilized for the diagnosis and control of diabetes in clinical practice. In this study, a sandwich paper-based electrochemiluminescence (ECL) biosensor has been developed using the zirconium metal-organic framework/Fe3O4(trimethyl chitosan)/gold nanocluster (Zr-MOF/Fe3O4(TMC)/AuNCs) nanocomposite as tracing tag to label anti-HbA1c monoclonal antibody and reduced graphene oxide (rGO) as immobilization platform of sensing element. The screen-printed electrodes (SPEs) were constructed and modified by sputtering a thick layer of gold on the paper substrate, followed by electrochemical reduction of aminophenylboronic acid (APBA)-functionalized GO to rGO/APBA, respectively. Different types of surface analysis methods were applied to characterize the Zr-MOF/Fe3O4(TMC)/AuNCs nanomaterials fabricated. Finally, antibody-labeled Zr-MOF/Fe3O4(TMC)/AuNCs nanocomposites were subjected to HbA1c in the sample and on the paper-based SPE. Quantitative measurement of HbA1c was performed using ECL and cyclic voltammetry (CV) over a potential range of - 0.2 to 1.7 V vs gold reference electrode with a sweep rate of 0.2 V.s-1 in the presence of triethylamine as a co-reactant after sandwiching the HbA1c target between antibody and APBA on the sensing area. This immunosensor demonstrated the desirable assay performance for HbA1c with a wide response range from 2 to 18% and a low detection limit (0.072%). This new strategy provides an effective method for high-performance bioanalysis and opens avenues for the development of high-sensitive and user-friendly device. Graphical abstract.