ScholarWorks@성균관대학교

초록

Traditional cathodic electrochemiluminescence (ECL) systems often require high excitation potentials, which can induce undesirable side reactions and structural degradation of biomolecules, thereby limiting their utility in bioanalytical applications. Herein, we report a low-potential ECL immunosensor for the ultrasensitive detection of neuron-specific enolase (NSE), utilizing carbon self-doped graphitic carbon nitride (CCN) as the luminophore. Synthesized via a hydrothermal-calcination approach, CCN features a modulated electronic structure, a narrowed bandgap (2.56 eV), and enhanced visible-light absorption, which collectively facilitate electron transfer and support efficient ECL emission at a reduced excitation potential of-1.2 V. Importantly, in situ generation of both sulfate (SO4 center dot-) and hydroxyl (center dot OH) radicals was achieved, and these species acted synergistically to amplify the ECL signal. This distinctive behavior underscores the previously unexplored applicability of CCN in ECL systems, where it serves not only as an effective emitter but also as a catalyst for radical-mediated signal generation under mild conditions. To ensure stable and efficient antibody immobilization, a carboxyl-functionalized interface was constructed by electropolymerizing 2-aminoterephthalic acid (ATA). The resulting immunosensor demonstrated a wide dynamic range (0.05 pg/mL to 100 ng/mL), a low detection limit (16.0 fg/mL), and excellent specificity, reproducibility, and operational stability. These findings highlight the potential of CCNbased low-voltage ECL platforms for sensitive biomarker detection and broaden the utility of carbon nitride materials in clinical diagnostics.

키워드