Tek Kullanımlık Karbon Elektrot ile Fluroksipir'in İlk Voltametrik Tespiti

Öz

Bu araştırmanın amacı, Fluroksipir'in (FLX) çevrede kalıcılığını ve voltammetri kullanarak zararlı etkilerini değerlendirmektir. Literatürde voltammetrik yöntemlerle FLX'in tayini üzerine herhangi bir çalışmaya rastlanmamış olması çalışmanın özgünlüğünü göstermektedir. Seçilen analitik yaklaşım, döngüsel voltammetri (CV) ve kare dalga voltammetrisi (SWV) kullanılarak tek kullanımlık kalem grafit elektrot (PGE) yüzeyinde gerçekleştirilmiştir. Elektrokimyasal ölçümler pH 3,00 fosfat tampon çözeltisi (PBS) ortamında gerçekleştirilmiştir. FLX, yaklaşık 1,40 V (Ag/AgCl) potansiyelinde iyi tanımlanmış bir oksidasyon piki vermiş ve elde edilen akım sinyalleri artan konsantrasyonlarla artmıştır. Kalibrasyon çalışmaları sonucunda SWV tekniği ile 4,00×10⁻⁷ – 8,00×10⁻⁵ M aralığında yüksek doğrusallık elde edilmiş, kalibrasyon eğrisinin eğimi 517737,74 μA/M ve korelasyon katsayısı (R²) 0,995 olarak hesaplanmıştır. FLX için tayin ve dedeksiyon limitleri sırasıyla 1,45×10⁻⁷ M (LOD) ve 4,39×10⁻⁷ M (LOQ) olarak belirlenmiştir. Analitik yöntemin gün içi ve günler arası tekrarlanabilirlik katsayıları sırasıyla %0,87 ve %0,96 olarak bulunmuştur. Ep-pH grafiğinden elde edilen eğim yaklaşık olarak –59 mV/pH olup, Ep-logv analizinden elde edilen n ≈ 2 değeri, FLX'in elektrokimyasal oksidasyon sürecinin iki elektron ve iki protonun transferi ile gerçekleştiğini doğrulamıştır.

Anahtar Kelimeler

• Herbisit
• Voltammetri
• Kalem grafit elektrot
• Algılama
• Oksidasyon
• Fluroksipir

First Voltammetric Detection of Fluroxypyr with Pencil Graphite Electrode from Real Samples

Öz

The goal of this investigation was to assess the persistence of Fluroxypyr (FLX) in the environment as well as its hazardous effects using voltammetry. The originality of this research is that no study on the determination of FLX by voltammetric methods has been found in the literature. The chosen analytical approach was carried out on the surface of a disposable pencil graphite electrode (PGE) utilising cyclic voltammetry (CV) and square wave voltammetry (SWV). Electrochemical measurements were carried out in pH 3.00 phosphate buffer solution (PBS) medium. FLX gave a well-defined oxidation peak at a potential of approximately 1.40 V (Ag/AgCl), and the obtained current signals increased with increasing concentrations. As a result of calibration studies, high linearity was obtained with SWV technique in the range of 4.00×10⁻⁷ – 8.00×10⁻⁵ M, the slope of the calibration curve was calculated as 517737.74 μA/M and the correlation coefficient (R²) was 0.995. The determination and detection limits for FLX were determined as 1.45×10⁻⁷ M (LOD) and 4.39×10⁻⁷ M (LOQ), respectively. Intra-day and inter-day repeatability coefficients of the analytical method were found to be 0.87% and 0.96%, respectively. The slope obtained from the Ep-pH plot was approximately –59 mV/pH and the value of n ≈ 2 obtained from the Ep-logv analysis confirmed that the electrochemical oxidation process of FLX occurred by the transfer of two electrons and two protons.

Anahtar Kelimeler

• Fluroxypyr
• Herbicide
• Voltammetry
• Pencil graphite electrode
• Detection
• Oxidation

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