DETECTION AND DISTINCTION OF PARAQUAT AND DIQUAT PESTICIDES MIXTURE VIA SPECTROELECTROCHEMISTRY

Henry Seitiro Kavazoi; Cibely da Silva Martin Sonvesso; Carlos José leopoldo Constantino; Priscila Alessio Constantino

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Paper Title

DETECTION AND DISTINCTION OF PARAQUAT AND DIQUAT PESTICIDES MIXTURE VIA SPECTROELECTROCHEMISTRY

Authors

Henry Seitiro Kavazoi
Cibely da Silva Martin Sonvesso
Carlos José leopoldo Constantino
Priscila Alessio Constantino

Modality

Pôster

Subject area

Dispositivos eletrônicos e ópticos (OLED/OFET/OPVs/etc.)

Publishing Date

12/12/2023

Country of Publishing

Brasil

Language of Publishing

Inglês

Paper Page

https://www.even3.com.br/anais/workshop-do-ineo-2023/613082-detection-and-distinction-of-paraquat-and-diquat-pesticides-mixture-via-spectroelectrochemistry

ISBN

978-65-272-0088-8

Keywords

Raman spectroelectrochemistry, screen-printed carbon electrodes, pesticides mixture

Summary

Emerging pollutants are a class of synthetic or natural compounds that significantly impact water quality. These compounds include surfactants, personal care products, pharmaceuticals, plasticizers, pesticides, and their degradation products, among others. Living organisms are often exposed to mixtures of these pollutants. However, studies typically focus on the effects of individual compounds or detect only one at a time due to the complexity of working with mixtures. Two herbicides, paraquat (PQ) and diquat (DQ), are widely used worldwide despite being highly toxic to human health and the environment. PQ has been banned in Brazil since September 2020, but DQ is still available for use. Although several electrochemical sensors have been developed for PQ and DQ, researchers are typically limited to detecting these herbicides individually due to the close potentials of their reduction and oxidation processes, which makes it challenging to differentiate them when mixed. Therefore, the purpose of this study was to detect and distinguish PQ and DQ herbicides using spectroelectrochemistry, which combines Raman spectroscopy and voltammetric techniques. Screen-printed carbon electrodes (SPCE) were used as a substrate. Raman spectra were collected by applying fixed potentials to bare SPCE for PQ, DQ, and an equimolar mixture (10-3 mol/L each). The Raman spectra collected corresponded to reduced species of PQ and DQ, as reported in the literature. The reductions occurred at different potentials for each herbicide, and the best spectra were collected at -0.73 V for PQ and -0.63 V for DQ. As a result, it was possible to distinguish the herbicides when applying potentials close to -0.73 V or -0.63 V in the equimolar mixtures. Spectroscopic and electrochemical techniques used separately may have low selectivity for detecting different compounds in complex mixtures. In such cases, the electrochemical and spectroscopic signals often provide results that include information about more than one process or substance. However, combining techniques can aid in the detection of substances present in the mixture since it is difficult to find two compounds that exhibit the same electrochemical behavior and identical spectroscopic properties. Acknowledgements: FAPESP (21/14235-6 and 18/22214-6); CNPq; CAPES.

Title of the Event: Workshop do INEO 2023
City of the Event: Nazaré Paulista
Title of the Proceedings of the event: Anais do Workshop INEO 2023
Name of the Publisher: Even3
Means of Dissemination: Meio Digital

How to cite

KAVAZOI, Henry Seitiro et al.. DETECTION AND DISTINCTION OF PARAQUAT AND DIQUAT PESTICIDES MIXTURE VIA SPECTROELECTROCHEMISTRY.. In: Anais do workshop INEO 2023. Anais...Nazaré Paulista(SP) Hotel Estância Atibainha, 2023. Available in: https//www.even3.com.br/anais/workshop-do-ineo-2023/613082-DETECTION-AND-DISTINCTION-OF-PARAQUAT-AND-DIQUAT-PESTICIDES-MIXTURE-VIA-SPECTROELECTROCHEMISTRY. Access in: 05/10/2024