Multiplex Electrochemiluminescence Polarization Assay Based on the Surface Plasmon Coupling Effect of Au NPs and Ag@Au NPs

A novel multiplex electrochemiluminescence (ECL) polarization assay was developed to detect breast cancer-related genes BRCA1 and BRCA2 simultaneously based on the polarization characteristics of surface plasmon-coupled electrochemiluminescence (SPC-ECL). In this work, boron nitride quantum dots (BN QDs) were used as ECL emitters, and gold nanoparticles (Au NPs) and gold-coated silver nanoparticles (Ag@Au NPs) were employed as surface plasmon materials. The surface plasmon coupling resonance of different metal NPs not only enhanced the ECL intensity but also converted the isotropic emission into directional emission. This study revealed the relation between the structure of metal nanomaterials and SPC-ECL, and a high polarization-resolved sensing system was designed to detect multitarget DNA from 100 aM to 1 nM simultaneously. Polarization-based multiple ECL analysis has broad prospects in related cancer diagnosis and treatment evaluation.