Authors: LOKMAN LİV, ZEKERYA DURSUN, NURİ NAKİBOĞLU
Abstract: This study describes a sensitive and accurate voltammetric method for determination of boron using metal nanoparticles/carbon nanotube modified electrodes. The oxidation peak of Alizarin Red S (ARS) at -0.59 V in the boron-ARS complex formed in ammonium/ammonia buffer solution (pH 8.5) was evaluated as a response. The electrode modification conditions and experimental parameters affecting the peak height were optimized. The characteristics of modified electrodes were investigated using cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscope, energy dispersive X-ray spectroscopy, high resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The limits of detection (3s$_{y/x})$ and the analytical ranges for gold nanoparticles/carbon nanotube modified electrode (AuNP/CNT/GCE) and copper nanoparticles/carbon nanotube modified electrode (CuNP/CNT/GCE) for 40 s accumulation times were 55 \textmu g L$^{-1}$ and 83 \textmu g L$^{-1}$ and 182-1500 \textmu g L$^{-1}$ and 278-1000 \textmu g L$^{-1}$, respectively. The method was applied to various water and eye drop samples. The results obtained for two modified electrodes were compared with inductively coupled plasma-mass spectrometry results and there was no statistically significant difference between the methods at 95% confidence level. Moreover, UME CRM 1201 (Elements in Spring Water) was used for the accuracy check of the proposed method.
Keywords: Boron, Alizarin Red S, nanoparticles, modified electrode, carbon nanotubes, voltammetry
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