A highly selective electrochemical sensor for trace determination and speciation of antimony (III & V) in water and soil samples using 2-thenoyltrifluoroacetone

Abstract

The current works extend the utility of 2-thenoyltrifluoroacetone reagent (HTTA) towards the least explored antimony (III & V) ions in complex matrices. The redox characteristics and the excellent surface coverage (Γ) of the electroactive antimony (III)-HTTA chelate onto the hanging mercury dropping electrode suggested establishing a differential pulse cathodic stripping voltammetric (DP–CSV) analysis for chemical speciation of antimony (III & V) in environmental water samples. Under the optimized conditions of pH, deposition time, potential, sweep rate, and HTTA concentration, the cathodic peak current at − 0.18 V linearly increased on growing antimony (III) concentration in a wide working range from 2.46 × 10−9 to 1.07 × 10−7 mol L−1, with an obtained detection and quantification limits 7.38 × 10−10 and 2.46 × 10−9 mol L−1, respectively. The figure of merits were compared successfully with some reported electrochemical, chromatographic, and spectrochemical methods. The established DP–CSV method has a unique advantages (rapid response, short analytical time, sensitive, selective, and reproducible) to be quantitatively applied for trace analysis of antimony (III & V) species in fresh and marine water (the Atlantic Ocean and the Red Sea) samples. The settled method was also validated (Student’s t and F tests at P = 0.05) by comparison with the official inductively coupled plasma-mass spectrometry (ICP-MS) method.