Functionalized\nTriangular Carbon Quantum Dot Stabilized\nGold Nanoparticles Decorated Boron Nitride Nanosheets Interfaced for\nElectrochemical Detection of Cardiac Troponin T

The\nfast, and highly sensitive estimation of cardiac troponin T\n(cTnT) is crucial for the early identification of acute myocardial\ninfarction (AMI). The electrochemical immunoassay-based (EIB) sensors\nare highly promising for this purpose, as they offer precise measurements\nand can be directly assessed in intricate matrices, including blood.\nTo increase sensitivity, EIB sensors use nanomaterials or amplification\nprocesses, which can be laborious to develop. With this, we develop\nan electrochemical immunosensor for the sensitive detection of cardiac\ntroponin T (cTnT). The sensing platform is composed of functionalized\ntriangular carbon quantum dots stabilized gold nanoparticles which\nare integrated with boron nitride nanosheets (caf-TCQDs@AuNPs on HO-BNNS).\nFerrocene carboxylic acid (Fc-COOH) serves as the signal label. The\ncomposite was developed and examined using several techniques such\nas X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS),\ntransmission electron microscopy (TEM), cyclic voltammetry, and chronocoulometry.\nThe caf-TCQDs@AuNPs supported on HO-BNNS, have a large surface area\nand excellent electrical conductivity, and serve as an effective platform\nfor the immobilization of anti-cTnT monoclonal antibodies via carbodiimide\ncoupling. The Fc-COOH, functioning as a signal label through the oxidation\nprocess, was integrated with caf-TCQDs@AuNPs on the HO-BNNS platform\nto establish an electrochemical immunosensor for the detection of\ncTnT. The electrochemical immunosensor demonstrated excellent performance\nfor the determination of cTnT under optimal conditions, exhibiting\na linearity range spanning from 0.0001 to 100 ng mL<sup>–1</sup>, accompanied by a low detection limit of 0.0013 ng mL<sup>–1</sup>. Notably, the immunosensor revealed high specificity, as well as\nexcellent levels of reproducibility and reliability for the examination\nof human serum samples.