Emamectin benzoate sensing using vivianenes (2D vivianites)

Surbhi Slathia; Bruno Ipaves; Raphael Benjamim de Oliveira; Guilherme da Silva Lopes Fabris; Marcelo Lopes Pereira Júnior; Raphael Matozo Tromer; Gelu Costin; Suman Sarkar; Douglas Soares Galvao; Chandra Sekhar Tiwary

arXiv · 2502.00813

Emamectin benzoate sensing using vivianenes (2D vivianites)

Surbhi Slathia·Bruno Ipaves·Raphael Benjamim de Oliveira·Guilherme da Silva Lopes Fabris·Marcelo Lopes Pereira Júnior·Raphael Matozo Tromer·Gelu Costin·Suman Sarkar·Douglas Soares Galvao·Chandra Sekhar Tiwary

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Abstract

The excessive application of pesticides, particularly the overreliance on insecticides for the protection of desirable crops from pests, has posed a significant threat to both ecological systems and human health due to environmental pollution. This research outlines a comprehensive approach to recognizing and quantifying the presence of insecticides through the application of spectroscopic and electrochemical sensing methods. The detection of Emamectin benzoate (EB), a commonly used insecticide, was performed utilizing vivianenes, a 2D phosphate that has been mechanically exfoliated from the naturally occurring vivianite minerals. This investigation examined the structural and compositional characteristics of vivianenes, utilizing a range of characterization methods. The spectroscopic analyses reveal the molecular interactions and structural modifications that take place during the interaction of EB with the 2D template. Electrochemical investigations employing cyclic voltammetry were performed for different concentrations of EB to enable real-time monitoring of the pesticide. The modified sensing electrode using vivianene demonstrated a linear range of from 50 mg/L to 10 micro g/L, effectively detecting EB molecules at levels significantly below the hazardous threshold. Fully atomistic molecular dynamics simulations were also carried out to obtain further insights into the interaction mechanisms of the EB with the vivianites, and the results corroborate the adsorption mechanism. Our results highlight the potential application of 2D phosphate minerals as advanced sensors to enhance agricultural monitoring and promote sustainable development.

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Surbhi Slathia, Bruno Ipaves, Raphael Benjamim de Oliveira, Guilherme da Silva Lopes Fabris, Marcelo Lopes Pereira Júnior, Raphael Matozo Tromer, Gelu Costin, Suman Sarkar, Douglas Soares Galvao, Chandra Sekhar Tiwary. 2025-02-02. Emamectin benzoate sensing using vivianenes (2D vivianites). https://arxiv.org/abs/2502.00813

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