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
International Journal of Environmental Analytical Chemistry, vol.104, no.18, pp.7046-7066, 2024 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 104 Issue: 18
- Publication Date: 2024
- Doi Number: 10.1080/03067319.2022.2161378
- Journal Name: International Journal of Environmental Analytical Chemistry
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Agricultural & Environmental Science Database, Aquatic Science & Fisheries Abstracts (ASFA), CAB Abstracts, Chemical Abstracts Core, Chimica, Compendex, Environment Index, Food Science & Technology Abstracts, Pollution Abstracts, Veterinary Science Database
- Page Numbers: pp.7046-7066
- Keywords: Inorganic Hg, ultrasound assisted-cloud point extraction, Poly(styrene-co-maleic anhydrite), 2-aminobenzimidazole, CTAB, liquid matrices, micro-volume UV-vis spectrophotometry
- Open Archive Collection: AVESIS Open Access Collection
- Sivas Cumhuriyet University Affiliated: Yes
Abstract
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 of the study lies in combining the pre-concentration of i-Hg with spectrophotometry after chelation with the 2-aminobenzimidazole modified amidic copolymer to increase the selectivity and sensitivity of the method. The method involves ultrasonic extraction of the samples in a dilute acid mixture of HClO4-HCl-CH3COOH and mixture of Cu(II)-oxalic acid-KCl adjusted to pH 5.0 in parallel, pre-con centration using UA-CPE process on modified amide copolymer, and absorbance measurement at 332 nm using a micro-volume UV-spectrophotometer. The figures of merit were discussed in relation with the demands in the national/international regulations and standards on the determination of toxic i-Hg in water intended for human consumption. After a pre-concentration of 62.5-fold, the limits of detection and quantification (LODs, LOQs) were 0.24 and 0.22 μg L−1 allowing the use of the method for i-Hg determination in liquid matrices such as cold-/hot-spring waters, plain soda, bottled drinking waters, and carbonated soft drinks. For concentrations of Hg22+, Hg2+ and total Hg in the range of