Innovative Real-Time Flow Sensor Using Detergent-Free Complex Emulsions with Dual-Emissive Semi-Perfluoroalkyl Substituted Α-Cyanostilbene

Adv Sci (Weinh). 2023 Nov;10(31):e2304108. doi: 10.1002/advs.202304108. Epub 2023 Sep 13.

Abstract

In this study, the potential of complex emulsions is investigated as transducers in sensing applications. Complex emulsions are stabilized without external detergents by developing a novel α-cyanostilbene substituted with PEG and semi-perfluoroalkyl chain (CNFCPEG). CNFCPEG exhibits unique variable emission properties depending on its aggregation state, allowing dual blue and green emissions in complex emulsions with hydrocarbon-in-fluorocarbon-in-water (H/F/W) morphology. The green excimer emissions result from the self-assembly of CNFCPEG at the fluorocarbon/water interface, while the blue emission observed is due to aggregation in the organic phase. A novel flow-injection method is developed by incorporating complex emulsions with CNFCPEG into multiple-well flow chips (MWFC). Iodine is successfully detected in a mobile aqueous solution by monitoring morphology changes. The findings demonstrate that self-stabilized complex emulsions with MWFC hold great promise for real-time sensing without costly instruments.

Keywords: aggregation-induced emission enhancement; complex emulsions; excimer emission; microfluidics; sensors.