Work

In situ formation of a Fe3O4@HgS nanocomposite for green preconcentration of Hg followed by detection with a direct mercury analyzer

Year: 2025

Type: article

Abstract: A novel method with a high greenness profile for the selective preconcentration and detection of Hg at ultratrace levels that involves magnetic nanoparticles has been developed. The ultrasonic decomposition of L-cysteine generated sulphide anion, which acts as a precursor for the formation of Fe 3 O 4 @HgS structures resulting in the efficient trapping of Hg(II) onto magnetite. Ultrasonic energy can be considered as green energy and L-cysteine is more environmentally friendly reagent than other sulphide precursors such as sodium sulphide. The magnetic sorbent allowed an easy phase separation using a magnet, thus avoiding centrifugation or filtration steps. A direct mercury analyzer allowed the direct and sensitive determination of the Hg collected onto the magnetic phase. A preconcentration factor of up to 91 and a limit of detection of 0.04 μg L -1 Hg can be achieved using a sample volume of 20 mL. Three reference materials were analyzed after application of the developed preconcentration method obtaining recoveries in the range 96-100 %. Additionally, water samples, including mineral water, tap water, seawater, fountain water and river water, were spiked at two levels of concentration, 5 and 10 μg L -1 , recoveries being in the range of 91-110 %. • >Fe 3 O 4 magnetic nanoparticles showed efficient preconcentration of Hg(II) in waters. • >The ultrasonic decomposition of L-cysteine allowed trapping of Hg(II) as Fe 3 O 4 @HgS. • >Direct mercury analyzer was used for Hg determination without elution. • >A limit of detection of 40 ng/L level can be obtained for Hg(II). • >Satisfactory recoveries are achieved after applying the method to water samples.

Source: Talanta

DOI: 10.1016/j.talanta.2025.129031

Authors: Aida González-Fernández, Inmaculada de la Calle, Vanesa Romero, Isela Lavilla, Carlos Bendicho

Institution: Universidade de Vigo

Language: English

Topic: Analytical chemistry methods development

Subfield: Analytical Chemistry

Field: Chemistry

Domain: Physical Sciences

SDG: Clean water and sanitation

Open Access status: hybrid

Estimated APC paid: $4,610