Polarized-Electrochemiluminescence Biosensor Based on Surface Plasmon Coupling Strategy and Fluorine-Doped BN Quantum Dots.

The first polarized-electrochemiluminescence (ECL) biosensor is reported in this work. Surface plasmon coupling ECL (SPC-ECL) strategy is developed for the amplified polarization light of fluorine-doped BN quantum dot (F-BN QD) emitters. The generation of polarized-ECL is attributed to the characteristic of polarization-angle-dependent SPC effect. A polarized sandwich-type biosensor based on F-BN QDs and Au nanoparticles (Au NPs) is established to detect the K-ras gene. The polarized-ECL sensor is more sensitive with lower detection limit than the isotropic ECL sensing system. The sensor can quantify the K-ras gene from 0.1 fM to 10 nM, with the detection limit as 0.03 fM. This work not only explores polarized SPC-ECL, but also offers a new analytical method for clinical diagnosis. The generation of polarized-ECL and the amplification strategy of the SPC effect opens a new path for ECL-resolved analyses.