Application of ultrasound assisted-cloud point extraction coupled with spectrophotometry for the selective extraction/pre-concentration of low levels of inorganic Hg (as Hg₂²⁺/Hg²⁺) from liquid matrices

This study presents the analytical characterisation of a low-cost, selective and sensitive method for inorganic Hg (as Hg22+/Hg2+) determination in liquid matrices based on spectrophotometry. The novelty lies combining pre-concentration i-Hg with spectrophotometry after chelation 2-aminobenzimidazole modified amidic copolymer to increase selectivity sensitivity method. involves ultrasonic extraction samples dilute acid mixture HClO4-HCl-CH3COOH Cu(II)-oxalic acid-KCl adjusted pH 5.0 parallel, pre-con centration using UA-CPE process amide copolymer, absorbance measurement at 332 nm micro-volume UV-spectrophotometer. figures merit were discussed relation demands national/international regulations standards toxic water intended human consumption. After 62.5-fold, limits detection quantification (LODs, LOQs) 0.24 0.22 μg L−1 allowing use such as cold-/hot-spring waters, plain soda, bottled drinking carbonated soft drinks. For concentrations Hg22+, Hg2+ total range <LOD, 0.35–4.20, 0.40–4.50 L−1, precision was 3.3–8.3%, below little above maximum 1.0 µg set mentioned legislation. recovery 92–96.4% 4.1–5.4% analysis two certified waters found be satisfactory, so validate developed is cost-effective enables us achieve complying European system has good potential future perspectives.