Synthesis of a New Cationic Polythiophene Derivative and Its Application for Colorimetric and Fluorometric Detection of Iodide Ion and Anionic Surfactants in Water

Abstract

A new cationic polythiophene derivative poly[3-(1,1 ′ -dimethyl-4-piperidinemethylene)thiophene-2,5-diyl chloride] (PDPMT-Cl) is synthesized and applied as a colorimetric and fl uorometric probe for the detection of iodide ion and anionic surfactants with high selectivity and sensitivity. Upon adding iodide ion or anionic surfactant into the aqueous solution of PDPMT-Cl, the maximum absorption of the polymer is blue-shifted with a naked-eye color change from red-violet to yellow, signifying that iodide ion or anionic surfactants can cause the dissociation of PDPMT-Cl aggregates. More sensitive results are obtained in the fl uorometric detection to iodide ion or anionic surfactant, thereinto, the detection limit to surfactants can be extended to the order of 10 − 9 M . applied to colorimetric probes for the detection of various bioanalytes. [ 1 − 8 ] However, few of them can be used to detect anionic substrates and the number of colorimetric sensors available at present for anionic substrates remains quite limited. The well-known anionic substrates detection techniques, such as capillary electrophoresis, [ 9 − 15 ] ion chromatography, [ 16 ] normal Raman spectroscopy, [ 17 ] gas chromatography/mass spectrometry (GC-MS), [ 18 ] highperformance liquid chromatography (HPLC), and fl uorescent detection (based on synthetic receptors), [ 19 , 20 ] to some extent, exist some limitations, including time-consuming, requiring expensive equipment, poor selectivity, and sensitivity. Therefore, it is the need of the hour to design new approaches that could improve simplicity, selectivity, and sensitivity.Many systems capable of recognizing, sensing, and transporting negatively charged species are based on supramolecular chemistry. Miyaji et al. [ 21 ] ever reported colorimetric detection of anions by calix[4]pyrrole, but it couldnot monitor the exact concentration, resulting in the limitation of its application. Moreover, though using polymeric membranes doped with various metalloporphyrins or polypyrroles to detect anions were also reported, [ 22 , 23 ] all of them were not still ideal enough to apply. However, E. Li et al.

Synthesis of polythiophene containing heterocycle on the side chain: A review

“…Using the layerby-layer assembly route in efficient inverted organic photovoltaic devices showed power conversion efficiency (PCE) of over 2% and remarkable longterm stability more than 500 hours. Scheme 6: Quaternization reaction to produce poly[3-(6-pyridiniumylhexyl)thiophene bromide] P7 [46] Scheme 7: Synthetic procedure of cationic poly (3-alkoxy-4-methylthiophene)s P8 [47] Hoang-Anh Ho et al synthesized a water soluble cationic poly(3-alkoxy-4-methylthiophene) containing N-methylimidazole substituent side-chain P8 from monomer 14 and the oxidative polymerization was prepared in anhydrous chloroform in the attendance of FeCl3 (scheme 7). [47] Thiophene monomer 15 was carried out from 3-(2-bromoethoxy)-4methylthiophene 14 and 1-methyl-imidazole in acetonitrile at 70 o C for 48 hours (yield 88 %).…”

An electrochemiluminescence sensor for bromate assay based on a new cationic polythiophene derivative

“…A new cationic polythiophene derivative PTh-D was prepared as described previously with some slight modifications [17]. 1.02 g FeCl 3 was dispersed in 20 mL dry chloroform and stirred for 30 min under nitrogen, and then a solution of 3-(1,1 0 -dimethyl-4-piperidinemethylene)thiophene methyl sulfate (0.50 g) in 20 mL chloroform was added drop wise to the above solution.…”

“…According to the literature of Li et al, PTh-D was synthesized successfully [17]. As such, it is our goal to investigate the ECL behavior of PTh-D and expand its potential applications in analytical chemistry field.…”

Polymers for Luminescent Sensing Applications

“…The sulfonate group‐containing taurine easily induced polymer aggregation by electrostatic interaction and also by π‐stacking and hydrophobic interactions, resulting in the concentration dependent color change. Cationic polyelectrolyte P13 was applied as a colorimetric and fluorometric probe for the detection of iodide ion and anionic surfactants (Figure b) . P13 was water soluble in an aggregate form.…”