Red‐Emitting Ratiometric Fluorescence Chemodosimeter for the Discriminative Detection of Aromatic and Aliphatic Amines

Abstract

A NIR-emitting fluorescent probe using phenothiazine and 1,3dimethylbarbituric acid (PMB) connected through methylene bridge was developed in a two-step simple chemical reaction. The fluorescent probes were highly reactive towards various primary amines and the reaction was accompanied by the changes in the optical and fluorescent properties of the PMB characteristic to the amine and thereby can have the potential to be used as a sensor for amines. In addition to the ratiometric changes in the fluorescence intensity corresponding to the PMB before and after reaction with an amine, the emission spectral maximum is specific to the analyte. For, example 1,4diaminobenzene, 4-methoxyaniline, aniline, hydrazine, ethyl-amine, ethylenediamine respectively shows the maximum at 532, 546, 555, 484, 497, and 488 nm and this unique feature originated due to the involvement of the analyte in the extended π-conjugation with the probe. Sensor strips prepared using PMB coated filter paper were able to sense the volatile amine gases with shorter response time. Analysis of the strips using the CIELAB 1976 color coordinates provides different signals for hydrazine, aniline, propylamine, and ethylamine gases. The applicability of the sensor was further ascertained by monitoring the decomposition of skin used for leather processing and also proteins engineered with an aminofunctionalized unnatural amino acid.[a]

Enlightening the Path to Protein Engineering: Chemoselective Turn-On Probes for High-Throughput Screening of Enzymatic Activity

“…A recent example of a red-emitting probe, PMB 21, was reported by Sathiskumar and Easwaramoorthi. 104 In this compound, phenothiazine and 1,3-dimethylbarbituric acid are connected via a methylene bridge. Fluorogenic properties of the probe are observed upon reaction with several primary aliphatic and electron-rich aniline systems.…”

“…A recent example of a red-emitting probe, PMB 21 , was reported by Sathiskumar and Easwaramoorthi . In this compound, phenothiazine and 1,3-dimethylbarbituric acid are connected via a methylene bridge.…”

Threonine-Based Stimuli-Responsive Nanoparticles with Aggregation-Induced Emission-Type Fixed Cores for Detection of Amines in Aqueous Solutions

“…The detection of amine compounds is of significant interest because they are widely utilized in several applications, such as pharmaceuticals, fertilizers, surfactants, and colorants, and are among the major pollutants detected in landfills, manufacturing sites, soils, and aqueous environments. Various fluorescence systems have been developed for the detection of aliphatic and aromatic amines, such as those using fluorescence chemodosimeters [ 29 ], metal–organic frameworks [ 30 ], Schiff base complexes [ 31 ], metalloporphyrins [ 32 ], conjugated polymers [ 33 ], and dyes with aggregation-induced emission [ 34 ]. Among the various amine compounds, intense efforts have been devoted to the detection of p -phenylenediamine (PPD), which is an important intermediate for hair dyes and polymers and has detrimental effects on the environment and human health.…”