Fluorescent polymer films based on photo-induced electron transfer for visualizing water

Abstract

Photo-induced electron transfer (PET)-type fluorescent polymer films based on a fluorescence enhancement system have been prepared as one of the most promising and convenient functional dye materials for visualizing moisture and water droplets.

Anthracene-(aminomethyl)phenylboronic acid ester-immobilized glass substrates as fluorescent sensing materials based on photo-induced electron transfer for detection and visualization of water

“…1a and b). 51 The DL and QL of SM-2 for water in acetonitrile were, respectively, 0.009 wt% and 0.028 wt%, which were equivalent to those of OF-2 . Interestingly, the spin-coated poly(SM-2- co -MMA) films on a glass substrate produced a reversible fluorescence off–on switching between the PET active state under a dry process and the PET inactive state upon exposure to moisture, which is demonstrated by the fact that the polymer film surface shows moderate hydrophilicity with a water contact angle of ca.…”

“…In recent years, there has been increasing interest in the development of fluorescent sensors and their functional materials, including polymers, membranes, and sensorimmobilized substrates for detecting and visualizing water in solids, solutions, and gas or on material surfaces, because such fluorescent sensing systems for water are crucial to environmental and quality control monitoring, industrial processes, food inspection and so on. Actually, some kinds of organic fluorescent sensors for water, based on ICT (intramolecular charge transfer), [25][26][27][28][29][30][31][32][33] ESIPT (excited state intramolecular proton transfer), [34][35][36][37] PET (photo-induced electron transfer), [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] or solvatochromism have been developed which exhibit photophysical changes in wavelength, intensity, and lifetime of fluorescence emission depending on the water content. Hence, over the last decade and a half, we continued to make much effort to design and develop PET-type fluorescent sensors for water in solvents.…”

Water detection in organic solvents using a copolymer membrane immobilised with a fluorescent intramolecular charge transfer-type dye: effects of intramolecular hydrogen bonds

“…Optical chemical sensors (optodes) have attracted considerable attention because of their simplicity; 10 therefore, numerous water-detecting optodes based on colourimetric and/or fluorescent dyes have been developed to date. 11–35 Fluorescence-based optodes are typically more sensitive than colourimetry-based optodes. The response mechanism of fluorescence-based optodes containing organic fluorophores can be classified based on the fluorescence mechanism 18,19 into photo-induced electron transfer (PET), 20–24 intramolecular charge transfer (ICT), 21,25–28 twisted ICT (TICT), 26,29,30 aggregation-induced emission (AIE), 24,29,30,32,33 and excited-state intramolecular proton transfer (ESIPT), 31,34,35 and so on.…”

“…11–35 Fluorescence-based optodes are typically more sensitive than colourimetry-based optodes. The response mechanism of fluorescence-based optodes containing organic fluorophores can be classified based on the fluorescence mechanism 18,19 into photo-induced electron transfer (PET), 20–24 intramolecular charge transfer (ICT), 21,25–28 twisted ICT (TICT), 26,29,30 aggregation-induced emission (AIE), 24,29,30,32,33 and excited-state intramolecular proton transfer (ESIPT), 31,34,35 and so on. In addition to the organic-fluorophore-based water detectors, other luminescent inorganic and/or organic water detectors – such as graphene quantum dots, 36 carbon dots (CDs), 37–40 covalent organic frameworks (COFs), 41–44 and metal–organic frameworks (MOFs) 39,45–47 – have been developed over the past decade.…”

“…In addition to the organic-fluorophore-based water detectors, other luminescent inorganic and/or organic water detectors -such as graphene quantum dots, 36 carbon dots (CDs), [37][38][39][40] covalent organic frameworks (COFs), [41][42][43][44] and metal-organic frameworks (MOFs) 39,[45][46][47] have been developed over the past decade. Besides, applications, 18 such as inkless writing, 32,38 paper strips, 25,[31][32][33]35,40 and luminophore-doped films 13,15,17,22,23,38 have been developed for simpler water detection as well as traditional solution-based measurement. Although various luminescent materials have been devised for water detection, most are suitable for recognising water in 1,4dioxane, tetrahydrofuran (THF), and acetonitrile.…”