Synthesis of a novel magnetic nanomaterial for the development of a multielemental speciation method of lead, mercury, and vanadium via HPLC-ICP MS

Abstract

A new magnetic functionalized material based on graphene oxide magnetic nanoparticles named by us, M@GO-TS, was designed and characterized in order to develop a magnetic solid-phase extraction method (MSPE) to enrich inorganic and organic species of lead, mercury, and vanadium. A flow injection (FI) system was used to preconcentrate the metallic and organometallic species simultaneously, while the ultra-trace separation and determination of the selected species were achieved by high-performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICP MS). Therefore, preconcentration and separation/determination processes were automated and conducted separately. To the best of our knowledge, this is the first method combining an online MSPE and HPLC-ICP MS for multielemental speciation. Under the optimized conditions, the enrichment factor obtained for PbII, trimethyllead (TML), HgII, methylmercury (MetHg), and VV was 27. The calculated LOD for all studied species were as follows: 5 ng L−1, 20 ng L−1, 2 ng L−1, 10 ng L−1, and 0.4 ng L−1, respectively. The RSD values calculated with a solution containing 0.5 μg L−1 of all species were between 2.5 and 4.5%. The developed method was validated by analyzing Certified Reference Materials TMDA 64.3 for total concentration and also by recovery analysis of the species in human urine from volunteers and a seawater sample collected in Málaga. The t statistical test showed no significant differences between the certified and found values for TMDA 64.3. All the recoveries obtained from spiked human urine and seawater samples were close to 100%. All samples were analyzed using external calibration. The developed method is sensitive and promising for routine monitoring of the selected species in environmental waters and biological samples. Graphical abstract

Atomic spectrometry update: review of advances in elemental speciation

“…No DMHg was detected in unspiked samples whilst spike recoveries, at 0.05, 0.2 and 1.0 ng L −1 , were all better than 93%. For the determination of Hg II and MeHg (and Pb II , TML and V V ) in seawater and urine, a SPE preconcentration was applied prior to HPLC-ICP-MS. 93 A previously synthesised, patented, magnetic nanomaterial based on a double coupling between GO and MNPs (M@GO) was further derivatised with the chelating group methyl thiosalicylate. The resulting M@GO-TS material (50 mg) was packed into a column mounted in the injection loop of a FI valve and sample, adjusted to pH 3.5, was loaded at 2.7 mL min −1 for 10 min.…”

Green chemistry: advancing planetary phosphorus sustainability through the synergy of graphene oxide modified with magnetic nanoparticles (M@GO) for extracting tertiary effluent phosphorus in sewage treatment plants

“…To date, M@GO has been effectively employed for the chemical analysis of metals in aqueous media as an on-line adsorbent. 26–28 However, its application on a larger scale in the field of environmental engineering remains unstudied. The objective of the current study was to assess the viability of M@GO as a phosphorus sorbent, for both its removal and recovery from real wastewater.…”