Polarization-Resolved Electrochemiluminescence Sensor Based on the Surface Plasmon Coupling Effect of a Au Nanotriangle-Patterned Structure

Abstract

This work focused on the construction of a nanomaterial-patterned structure for high-resolved ECL signal modulation. Due to the surface coupling effect, the different shapes and distribution states of surface plasmonic nanomaterials not only affect the luminescence intensity enhancement but also decide the electrochemiluminescence (ECL) polarization characteristics. Herein, tin disulfide quantum dots were synthesized via a solvothermal method as ECL emitters. Compared with other nanostructures, Au nanotriangle (Au NT) displayed both the localized surface plasmon resonance electromagnetic enhancement effect and the tip amplification effect, which had significant hot spot regions at three sharp tips. Therefore, self-assembled Au NT-based patterned structures with high density and uniform hot spots were constructed as ideal surface plasmonic materials. More importantly, the distribution states of the hot spots affect the polarization characteristics of ECL, resulting in directional ECL emission at different angles. As a result, a polarization-resolved ECL biosensor was designed to detect miRNA 221. Moreover, this polarization-resolved biosensor achieved good quantitative detection in the linear range of 1 fM to 1 nM and showed satisfactory results in the analysis of the triple-negative breast cancer patients’ serum.

Electrochemiluminescence with semiconductor (nano)materials

“…Surface plasmon coupling can also confer unusual properties to ECL 214 emission as exemplified with Au nano-triangles. 215 In this very recent report, these NPs were self-assembled at the electrode surface before ECL recording with SnS 2 QDs. The pattern not only provides the signal enhancement but also generates an anisotropic circular polarization.…”

Functional COFs for Electrochemical Sensing: From Design Principles to Analytical Applications

“…[262][263][264] For improved sensitivity highly efficient emitters with high ECL intensity are required. So far various materials such as QDs, metal nanostructures, metal halide perovskites, carbon-based nanomaterials, MOFs [265][266][267][268][269][270] and so on have been used as efficient ECL carriers. Especially COFs can remarkably enhance loading amount of ECL luminophores and promote the excitation of external and internal ECL emitters to produce strong ECL luminescence.…”

Asymmetric Heterodimer-Regulated Surface Plasmon Coupling ECL Polarization Strategy for MiRNA-182 Detection

“…13,14 In addition, the SPC effect has been studied in the ECL sensing developments with plasmonic nanostructures. 15,16 Among a large variety of plasmonic metal nanoparticle aggregates, heterodimers are promising as emerging unique nanostructures, which consist of two closely spaced adjacent NPs with asymmetric sizes or compositions. 17,18 Plasmonic heterodimers not only possess the functions of their different nanodomains but also generate novel characteristics, such as catalytic, optical, and magnetic properties.…”

“…LSPR is the collective excitation of free electrons of metal nanoparticles (NPs) in response to incident light, which can be tuned by modifying the size, geometry, chemical composition, and surrounding dielectric environment of metal NPs . In recent years, explorations have revealed that metal nanoparticle aggregates with narrow gap distances allow individual LSPRs to hybridize with each other, generating high-intensity electromagnetic hot spots in the gap region, resulting in the surface plasmon coupling (SPC) effect. , In addition, the SPC effect has been studied in the ECL sensing developments with plasmonic nanostructures. , …”