Fluorescence and Electrochemical Sensing of Pesticides Methomyl, Aldicarb and Prometryne by the Luminescent Europium-3-Carboxycoumarin Probe

Abstract

This work describes the application of time resolved fluorescence in microtiterplates and electrochemical methods on glassy carbon electrode for investigating the interactions of europium-3-carboxycoumarin with pesticides aldicarb, methomyl and prometryne. Stern-volmer studies at different temperatures indicate that static quenching dominates for methomyl, aldicarb and prometryne. By using Lineweaver-Burk equation binding constants were determined at 303 K, 308 K and 313 K. A thermodynamic analysis showed that the reaction is spontaneous with ΔG being negative. The enthalpy ΔH and the entropy ΔS of reactions were all determined. A time-resolved (gated) luminescence-based method for determination of pesticides in microtiterplate format using the long-lived europium-3-carboxycoumarin has been developed. The limit of detection is 4.80, 5.06 and 8.01 μmol L(-1) for methomyl, prometryne and aldicarb, respectively. This is the lowest limit of detection achieved so far for luminescent lanthanide-based probes for pesticides. The interaction of the probe with the pesticides has been investigated using cyclic voltammetry (CV), differential pulse polarography (DPP), square wave voltammetry (SWV) and linear sweep voltammetry (LSV) on a glassy carbon electrode in I = 0.1 mol L(-1) p-toluenesulfonate at 25 °C. The diffusion coefficients of the reduced species are calculated. The main properties of the electrode reaction occurring in a finite diffusion space are the quasireversible maximum and the splitting of the net SWV peak for Eu(III) ions in the ternary complex formed . It was observed that the increase of the cathodic peak currents using LSV is linear with the increase of pesticides concentration in the range 5 × 10(-7) to 1 × 10(-5) mol L(-1). The detection limit (DL) were about 1.01, 2.23 and 1.89 μmol L(-1) for aldicarb, methomyl and prometryne, respectively. In order to assess the analytical applicability of the method, the influence of various potentially interfering species was examined. Influence of interfering species on the recovery of 10 μmol L(-1) pesticides has been investigated.

Sensing of nucleosides, nucleotides and DNA using luminescent Eu complex by normal and time resolved fluorescence techniques

“…In addition, problems associated with autofluorescence and Rayleigh scattering are obviated [33]. The present study can be considered as a continuation for the author work in the field of analytical applications of lanthanide complexes [35][36][37][38][39][40][41].…”

“…Several methods have been reported for the determination of nucleoside and nucleotide concentrations in cells [21][22][23][24][25], biological samples [26,27] or milk [28]. High-performance liquid chromatography (HPLC) [34,36], liquid chromatography-mass spectrometry (LC-MS) [21][22][23]27], and LC/MS/MS [24,25,29] have been used for such measurements. However, the simultaneous determination of inosine, IMP, uridine, thymidine and cytidine has not been performed to date.…”

Time-resolved fluorescence sensing of pesticides chlorpyrifos, crotoxyphos and endosulfan by the luminescent Eu(III)–8-allyl-3-carboxycoumarin probe

“…Due to the structural similarity of pesticide compounds, it is also paramount that the designed sensors must be fabricated such that they are highly selective toward specific pesticide compounds. This work represents a continuation of our work in the field of development of novel luminescent sensors for environmental and biomedical applications [23][24][25][26][27][28][29].…”

Sensing and sensitive visualization of latent fingerprints on various surfaces using a versatile fluorescent aggregation‐induced emission‐based coumarin derivative

“…shown in Table 3. [48][49][50][51][52] F I G U R E 1 5 Schematic representation of elaborated redox reaction mechanism of CFD Nitrendipin-GC LSV 0.10 μM [38] Aldicarb pesticide-GC LSV 1.01 μM [39] Poly-MTRP-GC LSV 0.145 μM NEA-modified LSV 0.02 μM [42] CFD-GC LSV 0.88 μM Present work…”