Controllable and Low-Loss Electrochemiluminescence Waveguide Supported by a Micropipette Electrode

Abstract

One-dimensional molecular crystal waveguide (MCW) can transmit selfgenerated electrochemiluminescence (ECL), but heavy optical loss occurs because of the small difference in the refractive index between the crystal and its surroundings. Herein, we report a micropipette electrode-supported MCW (MPE/MCW) for precisely controlling the far-field transmission of ECL in air with a low optical loss. ECL is generated from one terminal of the MCW positioned inside the MPE, which is transmitted along the MCW to the other terminal in air. In comparison with conventional waveguides on solid substrates or in solutions, the MPE/MCW is propitious to the total internal reflection of light at the MCW/air interface, thus confining the ECL efficiently in MCW and improving the waveguide performance with an extremely low-loss coefficient of 4.49 × 10 −3 dB μm −1 . Moreover, by regulation of the gas atmosphere, active and passive waveguides can be resolved simultaneously inside MPE and in air. This MPE/MCW offers a unique advantage of spatially controlling and separating ECL signal readout from its generation, thus holding great promise in biosensing without or with less electrical/chemical disturbance.

Electrochemiluminescence Microscopy

“…Furthermore, using a micropipette electrode to support the molecular wire, precise control of ECL transmission can be achieved in air with low optical loss. [45] A large decrease in ECL intensity was observed upon the injection of O 2 , which makes this device suitable for oxygen detection. This ECL waveguide opens up new prospects for contactless electrochemical analysis and remote imaging (i.e., intracellular biosensing) and the study of (bio)chemical systems without electric/chemical disturbance.…”

“…Original strategies for the wireless electrochemical generation of ECL at specifically-designed waveguides have been coupled with a simultaneous remote readout. [43][44][45] Remarkably, Su and co-workers reported an original imaging based on molecular wires that serve as both ECL emitters and waveguides. [44,45] Self-generated ECL from crystalline molecular wires exhibit typical characteristics of optical waveguides, including transmitting ECL and brighter emissions at their terminals.…”

“…[43][44][45] Remarkably, Su and co-workers reported an original imaging based on molecular wires that serve as both ECL emitters and waveguides. [44,45] Self-generated ECL from crystalline molecular wires exhibit typical characteristics of optical waveguides, including transmitting ECL and brighter emissions at their terminals. Furthermore, using a micropipette electrode to support the molecular wire, precise control of ECL transmission can be achieved in air with low optical loss.…”