Organic Luminescent Sensor for Mercury(II) and Iron(III) Ions in Aqueous Solutions

Abstract

The substrate N1, N3, N5-tris(2-hydroxyphenyl)benzene-1,3,5-tricarboxamide (Sensor A) was prepared in the reaction of 1,3,5-benzenetricarboxylic acid (trimesic acid) and o-aminophenol in ethanol. The prepared organic sensor fulfills the chemiluminescent requirements including a luminophore, spacer, and suitable binding receptor that distress the probe’s luminescent features, providing selective and sensitive detection of mercury and iron ions in aqueous solutions. The sensor selectively detects mercury and iron ions in a water matrix containing various metal ions, including sodium, calcium, magnesium, zinc, and nickel. Strong and immediate binding was observed between mercury ions and the substrate at pH 7.0 with a binding affinity toward Hg2+ 9-fold higher than that observed for iron sensor binding affinity, which makes the substrate a distinctive luminescence sensor for mercury detection at ambient conditions. The sensor shows a linear response toward Hg2+ in the concentration range from 50 ppb to 100 ppm (2.0 × 10−8 to 4.2 × 10−5 M) with a limit of detection of 2 ppb (1.0 × 10−8 M). Further, Sensor A provides linear detection for iron ions in the range from 10 ppb to 1000 ppm (1.5 × 10−8 to 1.5 × 10−3 M). The measured adsorption capacity of Sensor A toward mercury ions ranged from 1.25 to 1.97 mg/g, and the removal efficiency from water samples reached 98.8% at pH 7.0. The data demonstrate that Sensor A is an excellent probe for detecting and removing mercury ions from water bodies.

Highly selective and sensitive fluorescent probes for nitrofurazone and Hg2+ by two Zn (II)‐based coordination polymers

“…The contamination in the water bodies by heavy metal ions especially mercury has been a great concern across the globe. Mercury is one of the most toxic elements in the ecosystem and is widespread in soil, air, and even freshwater bodies 1–3 . The major sources of the release of mercury into the environment include coal burning, mining activities, and combustion of fossil fuels.…”

“…Mercury is one of the most toxic elements in the ecosystem and is widespread in soil, air, and even freshwater bodies. [1][2][3] The major sources of the release of mercury into the environment include coal burning, mining activities, and combustion of fossil fuels. Also, certain chemical industries linked with the use of chlor-alkali and pesticides contribute in elevating the levels of mercury in the environment.…”