1. Optimisation of a sample preparation method for the determination of multi-elemental compositions in human hair by triple quadrupole ICP-MS analysisAgneta Annika Runkel, Marta Jagodic Hudobivnik, Igor Živković, Polona Klemenčič, Darja Mazej, Milena Horvat, 2026, izvirni znanstveni članek Povzetek: Monitoring toxic elements has a long tradition in Slovenia due to historical mining. More recently, attention has shifted to essential elements, since both deficiencies and excesses can harm health. Regular monitoring of (non-)essential elements supports risk assessment and policymaking. While urine and blood are common biomonitoring matrices, hair offers a non-invasive alternative that reflects exposure over several months, though standardised methodologies for hair analysis remain limited. This study aimed to develop and validate a sensitive and robust analytical method for the determination of 29 elements in human hair, addressing key challenges in sample preparation and contamination control. We developed a sensitive and robust method for the determination of 29 elements (Ag, Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Se, Sn, Sr, Ti, U, V, and Zn) in 3 cm segments of human hair that involves a washing procedure with acetone and Milli-Q water, microwave digestion with 65% HNO3, and analysis with Triple Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS/MS). Evaluation of preparation steps revealed stainless-steel scissors as a major contamination source. Glass digestion vessels were unsuitable for several elements due to high detection limits and relative standard deviations. The optimised method reduced analytical variability and improved sensitivity compared to published protocols. This validated method enables reproducible multi-elemental analysis in hair, highlights overlooked contamination risks, and is now applied in human biomonitoring studies to strengthen exposure assessment and standardisation efforts.
Ključne besede: determination of elements, optimization, human biomonitoring
Objavljeno v DiRROS: 27.01.2026; Ogledov: 182; Prenosov: 105
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2. Green synthesis of a magnetite/graphitic carbon nitride 2D nanocomposite for efficient ▫$Hg^{2+}$▫ remediationRaghuraj S. Chouhan, Jan Gačnik, Igor Živković, Sreekanth Vijayakumaran Nair, Nigel Willy Van de Velde, Alenka Vesel, Primož Šket, Sonu Gandhi, Ivan Jerman, Milena Horvat, 2023, izvirni znanstveni članek Povzetek: Novel nanoadsorbents demonstrate the potential to efficiently eliminate harmful substances, such as Hg2+, from the environment while preserving ecological balance. However, the search for environmentally-friendly nanomaterials as ideal adsorbents, as well as the development of suitable synthesis protocols, remains a challenge. This study presents an effective thermal-sonication technique for producing unique de novo tris-s-triazine carbon nitride nanosheets decorated with magnetite nanoparticles (M-g-CN). The structural integrity and chemical properties of the M-g-CN nanocomposite were extensively characterized using a battery of analytical instruments, including FTIR, SEM, TEM, XRD, XPS, AFM, Raman, and NMR. The obtained data, along with the analysis results, are discussed in detail. The novel synthesis method yields a high percentage (97.7%) of stable, highly selective, and reusable M-g-CN (40 mg mL−1). The resulting M-g-CN effectively binds Hg2+, with binding efficiencies of 96.0%, 97.5%, 98.2%, and 99.4% for Hg2+ concentrations of 50 pg mL−1 in marine, stream, precipitation, and ultra-pure matrices, respectively. Also, the magnetite-decorated particles can be easily retrieved using an applied magnetic field. This greener and scalable synthesis method does not require harsh chemicals, making it cost-effective, eco-friendly, and non-toxic compared to other technologies such as carbon filters, ion exchange resins, chemical precipitation, membrane filtration, electrochemical methods, and biological remediation. Overall, the synthesized M-g-CN exhibits wide-ranging potential applications, particularly as a green adsorbent in passive samplers or materials for remediation purposes.
Ključne besede: mercury, elimination, nanoadsorbents, nanocomposites
Objavljeno v DiRROS: 05.01.2026; Ogledov: 282; Prenosov: 107
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3. Achieving measurement comparability in mercury speciation analysis in seawater : Key requirements and best practicesIgor Živković, Lars-Eric Heimbürger-Boavida, Mariia V. Petrova, Aurélie Dufour, Ermira Begu, Milena Horvat, 2025, izvirni znanstveni članek Povzetek: The comparability of measurement results is an important issue in contemporary mercury (Hg) speciation in seawater. Sampling campaigns must be properly designed to determine significant differences on spatial and temporal scales, considering two major parameters: the variability of expected data at a given sampling point/ transect and variability in the results due to the intrinsic properties of specific analytical methods, particularly the measurement uncertainty. This study assessed the required sample size, considering several aspects of data variability when determining total Hg, dissolved gaseous Hg, and methylated Hg species in seawater. The required sample sizes were calculated using (1) the measurement uncertainty of a single-laboratory measurement of analytical methods used; (2) performance of the laboratories in interlaboratory comparison exercises; and (3) natural variability in Hg species/fractions in a selected case study in the Central Adriatic Sea. It was shown that the measurement uncertainty of a particular method and interlaboratory variability among laboratories have significant influence on data interpretation in case natural variability of Hg fractions is relatively small, such as for example the open seawater depth profiles. In contrary, in areas with large natural variability of Hg con tractions, such as coastal and contaminated sites, their influence on data interpretation is negligible. The present paper introduces the importance of proper estimation of measurement uncertainty in international programs, such as GEOTRACES, where data comparability is of fundamental importance to assess temporal and spatial trends of Hg measurements in the marine environment
Objavljeno v DiRROS: 05.09.2025; Ogledov: 486; Prenosov: 124
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