A Benzothiazole-Based Fluorescence Turn-on Sensor for Copper(II)

Abstract

A new benzothiazole-based chemosensor BTN (1-((Z)-(((E)-3-methylbenzo[d]thiazol-2(3H)ylidene)hydrazono)methyl)naphthalen-2-ol) was synthesized for the detection of Cu 2+ . BTN could detect Cu 2+ with "off-on" uorescent response from colorless to yellow irrespective of presence of other cations.Limit of detection for Cu 2+ was determined to be 3.3 µM. Binding ratio of BTN and Cu 2+ turned out to be a 1:1 with the analysis of Job plot and ESI-MS. Sensing feature of Cu 2+ by BTN was explained with theoretical calculations, which might be owing to internal charge transfer and chelation-enhanced uorescence processes.

Thioflavin-T-Enhanced Fluorescence in Cerium Adenosine Triphosphate Coordination Polymer Nanoparticles for Selective and Sensitive Copper(II) Detection in E-Waste and Biological Samples

“…It should be noted that while literature reports are available regarding the determination of Cu­(II) in various matrixes using fluorescence techniques (Table ), in most of the cases, the performance of the methodology has been demonstrated in a simpler matrix like deionized water, , water/organic solvent, , or buffer solutions. − Only in limited cases, the performance assessment was carried out in wastewater, urine, ascites fluid, and serum samples …”

Design, Synthesis and Evaluation of Fluorescent Properties of Benzothiazole Derivatives

“…All chemical materials were reagent grade and used as purchased. 1 H NMR and 13 C NMR spectra were recorded on a Bruker AVIII 400 MHz spectrometer. The chemical shifts were reported in (ppm) using the 2.50 signal of DMSO ( 1 H NMR) as internal standards and the 39.52 signal of DMSO ( 13 C NMR) as internal standards.…”

“…[7][8] What's more, the technique can be detected in vivo and does not rely on special or expensive instruments, [9][10][11] which also leads to the widely used in bioimaging. Organic fluorescent molecules are an important part of fluorescent tools, [12] although fluorescent proteins are widely used today, small molecular fluorescent compounds are still important as labeling agents and sensors, [13][14] because they are applicable to any sample, also relatively inexpensive and easier to handle. [15] However, some reported small molecular fluorescent compounds exhibited low tissue pene-tration or spatial resolution, which had a limitation for their further bioimaging applications.…”

Copper (II)-Catalyzed Oxidation of Ascorbic Acid: Ionic Strength Effect and Analytical Use in Aqueous Solution

“…In our opinion, it is a good result in comparison even with more complex fluorimetric techniques using sophisticated chemosensors. Although the kinetic method using ascorbic acid oxidation shows higher LOD for Cu 2+ than 20 nM [35], 4.7 nM [36], and 24.5 nM [37] and slightly higher than LOD of inductively coupled plasma-atomic emission spectroscopy (74 nM [54]), this technique is more sensitive than the reported fluorescent ones [38][39][40][41][42][43][44][45][46][47][48], atomic absorption spectroscopy (AAS) [49] (however, preconcentration methods [50][51][52] improves the sensitivity of AAS by 10 times compared to the proposed method) and atomic emission spectroscopy [54]). Another advantage of the proposed method is its probable applicability for determining the equilibrium concentration of copper (II) ions in complex systems containing ligands (including biomacromolecules such as nucleic acids and proteins), i.e., for studying the coordination equilibria and determining the stability constants of Cu 2+ complexes.…”

“…It is worth noting that other analytical methods of copper (II) determinations are known, including the classic ones (chelatometry, coulometry, etc.) and several fluorimetric sensors designed recently (see, e.g., just a few of them in papers [35][36][37][38][39][40][41][42][43][44][45][46][47][48]). However, the relatively low sensitivity and selectivity are the disadvantages of the classic techniques, and a preconcentration of copper (II) is required to achieve the nanomolar limit of detection using atomic absorption spectroscopy [49][50][51][52], while the fluorescent sensors are often difficult to synthesize.…”