This study describes a sensitive and accurate voltammetric method for determination of boron using metalnanoparticles/carbon nanotube modified electrodes. The oxidation peak of Alizarin Red S (ARS) at –0.59 V in the boronARS 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 modifiedelectrodes were investigated using cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscope, energy dispersive X-ray spectroscopy, high resolution transmission electron microscopy, and X-ray photoelectronspectroscopy. The limits of detection (3s y/x) and the analytical ranges for gold nanoparticles/carbon nanotube modifiedelectrode (AuNP/CNT/GCE) and copper nanoparticles/carbon nanotube modified electrode (CuNP/CNT/GCE) for40 s accumulation times were 55 µg L −1and 83 µg L −1and 182–1500 µg L −1and 278–1000 µg L −1, respectively.The method was applied to various water and eye drop samples. The results obtained for two modified electrodes werecompared with inductively coupled plasma-mass spectrometry results and there was no statistically significant differencebetween the methods at 95% confidence level. Moreover, UME CRM 1201 (Elements in Spring Water) was used for theaccuracy check of the proposed method.