David Milde

This review discusses developments in elemental mass spectrometry, atomic absorption, emission and fluorescence, XRF and LIBS, as applied to the analysis of specimens of clinical interest, foods and beverages. Sample preparation procedures and quality assurance are also included.

This Update covers publications from the second half of 2023 to the middle of 2024, related to the analysis of clinical specimens, food and beverages and including reviews discussing specific aspects and future perspectives. The pursuit of lower detection capabilities continues to promote further research. Some works have focussed on vapour generating techniques for trapping and preconcentration prior to instrumental analysis and many more on the extraction and preconcentration of elements during the sample preparation step. The synthesis and application of nanomaterials play an important role for these developments. The interest in reagents for green chemistry was the subject of several reviews, and, increasingly, researchers are discussing the environmental impact and sustainability of new methods. In terms of analytical instrumentation, the performances of MICAP-OES were thoroughly assessed on various complex matrices, confirming the technique as highly robust to interferences and with detection capabilities similar to ICP-OES. The N₂-MICAP-MS, which is free from Ar-based polyatomic interferences, was applied to human serum and food samples, although with no significant advantage. There was continued interest in applications of scICP-TOF-MS for the evaluation of more than one characteristic of the same individual cell. The determination of isotope ratios in biological matrices was carried out by high precision MC-ICP-MS. The interest in single cell and single particle analysis and the determination of nanoparticles resulted in the publication of multiple papers specifically reviewing the development in these areas, from which the need emerged to apply multiple techniques and promote standardisation. Multielement techniques (LIBS and XRF) are increasingly applied both in the clinical and food area. Several papers reported new applications of LIBS for disease diagnosis, based on complex statistical modelling methods, whereas others have focussed on techniques to enhance its sensitivity and precision for the analysis of biological, food and water samples. Portable LIBS instrumentation offers potential for a wider application in forensic and food sciences, if calibration strategies and method validation could be improved. The indirect detection of low concentrations of molecules of clinical interest after element-tagging represents a rapidly expanding field. Applications of atomic spectrometry to food and beverages continue to grow, especially in relation to sustainable diets and food supplements. The trend of investigations of authenticity/provenance of foodstuffs using multielement profiles continues. The quality of analytical measurements should be of the utmost importance, however still too often such information is insufficient. We therefore highlight the analysis of CRMs in the papers discussed in this Update and report publications addressing interlaboratory comparisons and new CRMs.

Cancer cell selective antiproliferative activity of thiadiazole-based half-sandwich complexes in sensitive and resistant ovarian cancer cell lines is triggered by exchanging Ru for Ir and by switching the halido coligand from chloride to iodide.

Platinum-based agents unwaveringly hold their prominent position in cancer treatment. Current research emphasizes finding novel complexes for hard-to-treat cancers with minimum side effects, capable of overcoming resistance. This work presents easy-to-prepare diiodidoplatinum(II) complexes cis-[PtI₂(Lⁿ)₂] (1–7) with imidazole derivatives (Lⁿ), which were considerably effective against multiple myeloma cell lines U266B1 and KMS12-PE. The leading compound 6 (at 3 μM concentration) extraordinarily reduced viability of U266B1 and KMS12-PE myeloma cells to 3.0% and 1.1%, respectively, and exceeded the conventional platinum-based anticancer drug cisplatin (93.1% and 88.3%, respectively) that is used clinically for the combination therapy of multiple myeloma. Complex 6 was significantly more effective in inducing apoptosis in KMS12-PE cells without interleukin-6 (IL-6) expression than in U266B1 cells with IL-6 expression. Complex 6 also induced apoptosis in co-culture of KMS12-PE with non-cancerous stromal fibroblasts (HS-5), and displayed markedly lower activity in the HS-5 stromal fibroblast cells than in myeloma cells, pointing out its pharmocologically prospective selectivity towards the cancer cells over the normal ones. No caspase 3/7 activity was detected in apoptotic KMS12-PE cells treated by complex 6 indicating a different mechanism of apoptosis action from cisplatin. This work demonstrates that simple non-classical platinum(II) complexes represent a new perspective for a monotherapy of hard-to-treat multiple myeloma.

This unique study provides information on Cr species and their distribution in periprosthetic tissues of patients with metal-on-polyethylene joint implants. Co-Cr-Mo alloy has been widely used in joint replacement and represents a source of metal derived species. In the case of chromium, previous studies on periprosthetic tissues revealed mainly Cr(III) distribution, whereas the potential release of carcinogenic Cr(VI) species has been still a subject of debate. Here, an analytical approach utilizing speciation and fractionation was developed to analyze periprosthetic tissue samples collected from wide range of patients with failed total hip or knee replacements. The results reveal that Cr(III) is mainly released in the form of insoluble CrPO4 and Cr2O3 particles. The highest Cr contents were found in periprosthetic tissues of patients suffering from aseptic loosening and having more Cr-based implants in the body. Cr species penetrated tissue layers, but their levels decreased with the distance from an implant. The detailed speciation/fractionation study carried out using the set of consecutive periprosthetic tissues of a patient with extensive metallosis showed the presence of trace amounts of free Cr(III), nanoparticles, and metal-protein complexes, but the majority of Cr still occurred in CrPO4 form. Carcinogenic Cr(VI) species were not detected. Up to date, there is no published human tissue study focused on the detailed speciation of both soluble and insoluble Cr-based species in the context of failing total hip and knee replacements.

The extent of interactions with various biomolecules is a crucial feature of newly developed metallodrugs, worthy of thorough investigation, as its understanding helps uncover the fate of these xenobiotics in the physiological environment. In this work, promisingly cytotoxic half-sandwich complexes [Ru(η⁶-pcym)Cl(L¹)]PF₆ (1), [Ir(η⁵-Cp*)Cl(L¹)]PF₆ (2) and [Ir(η⁵-Cp*)Cl(L²)]PF₆ (3), with 2-{n-[(E)-phenyldiazenyl]pyridin-2-yl}-1H-benzimidazole as a bidentate N-donor azo ligand (n = 5 for L¹ and 6 for L²; pcym = p-cymene, Cp* = pentamethylcyclopentadienyl), were subjected to an extensive and detailed study of interactions with a plethora of extra- and intracellular biologically relevant molecules. For the first time in the field of anticancer half-sandwich complexes, mixtures of 3 with ascorbic acid (ASA) and its combinations with reduced glutathione (GSH) and/or reduced nicotinamide adenine dinucleotide (NADH) were studied. Complex 3 undergoes azo bond reduction when mixed with NADH or ASA, which oxidizes to NAD⁺ or dehydroascorbate (DHA), respectively. Intriguingly, the presence of the natural antioxidant ASA has a relevant prooxidative impact on GSH, which is connected with ASA recovery from DHA. Although the azo bond of L² involved in 3 seems to be the reaction centre for the dehydrogenation reactions of the biomolecules, L² by itself is a negligible oxidant and thus complexation in 3 represents a necessary prerequisite for the redox reactions.

The hydrolytically stable half-sandwich complex [Os(η⁶-pcym)(L2)Cl]PF₆ (2) partially releases the bioactive substituent indomethacin in the presence of carboxypeptidase A.

The monitoring of water quality in the EU is described in detail and regulated by Directives of the European Commission and the Parliament, which underlines the importance of the quality of water (both potable and non-potable). Analysis of trace concentrations of contaminants in water, including metals, still presents challenges to demonstrate the quality and comparability of results. The article provides a detailed overview of the procedures that laboratories can use to assess the reliability of the results obtained by a particular measurement procedure. Emphasis is placed on three basic pillars: metrological traceability, validation and measurement uncertainty. Subsequently continuous evaluation is carried out using internal and external quality management measures. Regional aspects specific for the Czech Republic are also mentioned.

Due to the extensive use of antimicrobial agents in human and veterinary medicine, residues of various antimicrobials get into wastewater and, subsequently, surface water. On the one hand, a combination of processes in wastewater treatment plants aims to eliminate chemical and biological pollutants; on the other hand, this environment may create conditions suitable for the horizontal transfer of resistance genes and potential selection of antibiotic-resistant bacteria. Wastewater and surface water samples (Morava River) were analyzed to determine the concentrations of 10 antibiotics and identify those exceeding so-called predicted no-effect environmental concentrations (PNECs). This study revealed that residues of five of the tested antimicrobials, namely ampicillin, clindamycin, tetracycline, tigecycline and vancomycin, in wastewater samples exceeded the PNEC. Vancomycin concentrations were analyzed with respect to the detected strains of vancomycin-resistant enterococci (VRE), in which the presence of resistance genes, virulence factors and potential relationship were analyzed. VRE were detected in 16 wastewater samples (11%) and two surface water samples (6%). The PNEC of vancomycin was exceed in 16% of the samples. Since the detected VRE did not correlate with the vancomycin concentrations, no direct relationship was confirmed between the residues of this antimicrobials and the presence of the resistant strains.