REPOSITORY
THE NICOLAUS COPERNICUS UNIVERSITY
IN TORUŃ
is an institutional repository of Nicolaus Copernicus University in Toruń. The task of the Repository is to promote scientific achievements and research conducted at NCU and to support teaching.
Recent Submissions
Experts' Opinions on the Impact of Community Archives on Archival Science, Archival Institutions and the Archival Profession
(State Archival Service of Ukraine, 2025-04-14) Wiśniewska-Drewniak, Magdalena; Kapała, Adriana
The article analyzes interviews with 12 experts from Poland and abroad on their perceptions of the impact of community (independent) archives on archival science as an academic discipline, on heritage institutions (especially public archives) and on the archival profession. The purpose of the work is to present the partial results of the project entitled «The impact of independent community archives». Methodology. Data were collected through semi-structured qualitative interviews, which were then analyzed using a priori codes (based on literature and previous interviews with community archivists), supplemented with new codes – new meanings observed during the iterative analysis performed by two team members. Scientific novelty: The article is the first study analyzing expert opinions on the impact of community archives, comparing views of different types of experts (e. g. academics, advocates for community archives, active or former community archivists). Prospects for further studies: Future research should also analyze the contributions of people from other cultures, continents and archival traditions, and should be based on sources that directly describe the influence of community archives on archival science and archival practice. Conclusions. Experts pointed to the significance of community archives in reshaping the foundations of archival science (e. g. terminology, archival value). Experts from Anglophone countries and Chile emphasized the relationship of community archives to decolonization of archives and critical archival studies. Experts from continental Europe focused on the acceptance of the existence of grassroots archives and their distinct archival practices. Some experts noted the impact on archival education. Experts variously assessed the effect on the practice of public archives.
Reactivity of non-organometallic ruthenium(II) polypyridyl complexes and their application as catalysts for hydride transfer reactions
(Frontiers, 2023) Chrzanowska, Marta; Katafias, Anna; van Eldik, Rudi
Recently, we investigated the substitution behavior of a series of ruthenium(II) complexes of the general formula [RuII(terpy)(N∧N)Cl]Cl, where terpy = 2,2′:6′,2″-terpyridine, N∧N = bidentate ligand, in aqueous solutions. We have shown that the most and least reactive complexes of the series are [RuII(terpy)(en)Cl]Cl (en = ethylenediamine) and [RuII(terpy)(phen)Cl]Cl (phen = 1, 10-phenantroline), respectively, as a result of different electronic effects provided by the bidentate spectator chelates. Polypyridyl amine Ru(II) complex, viz. [Ru(terpy)(en)Cl]Cl and [Ru(terpy (ampy)Cl]Cl (where ampy = 2-(aminomethyl)pyridine), in which the terpy chelate labilizes the metal center, are able to catalyze the conversion of NAD+ to 1,4-NADH using sodium formate as a source of hydride. We showed that this complex can control the [NAD+]/[NADH] ratio and potentially induce reductive stress in living cells, which is accepted as an effective method to kill cancer cells. Polypyridyl Ru(II) complexes, characterized in terms of the behavior in aqueous solutions, can be used as model systems to monitor heterogeneous multiphase ligand substitution reactions at the solid-liquid interface. Colloidal coordination compounds in the submicron range were synthesized from Ru(II)-aqua derivatives of starting chlorido complexes via the anti-solvent procedure and stabilized by a surfactant shell layer.
A Personal Account on Inorganic Reaction Mechanisms
(The Chemical Society of Japan and Wiley-VCH GmbH, 2023) Polaczek, Justyna; Kieca, Konrad; Oszajca, Maria; Impert, Olga; Katafias, Anna; Chatterjee, Debabrata; Ćoćić, Dušan; Puchta, Ralph; Stochel, Grażyna; Hubbard, Colin D.; van Eldik, Rudi
The presented Review is focused on the latest research in the field of inorganic chemistry performed by the van Eldik group and his collaborators. The first part of the manuscript concentrates on the interaction of nitric oxide and its derivatives with biologically important compounds. We summarized mechanistic information on the interaction between model porphyrin systems (microperoxidase) and NO as well as the recent studies on the formation of nitrosylcobalamin (CblNO). The following sections cover the characterization of the Ru(II)/Ru(III) mixed-valence ion-pair complexes, including Ru(II)/Ru(III)(edta) complexes. The last part concerns the latest mechanistic information on the DFT techniques applications. Each section presents the most important results with the mechanistic interpretations.
Analysis of Photocatalytic Properties of Poly(MethylMethacrylate) Composites with Titanium(IV) and Ruthenium(III) Complexes
(MDPI, 2025) Kubiak, Barbara; Topolski, Adrian; Radtke, Aleksandra; Muzioł, Tadeusz; Impert, Olga; Katafias, Anna; van Eldik, Rudi; Piszczek, Piotr
This study explores poly(methyl methacrylate) (PMMA)-based composites as potential alternatives to conventional TiO2-based photocatalysts. Specifically, it examines PMMA composites enriched with oxo–titanium(IV) complexes, [Ti8O2(OiPr)20(man)4] (1), [Ti4O(OiPr)10(O3C14H8)2] (2), and [Ti6O4(OiPr)2(O3C14H8)4(O2CEt)6] (3), alongside ruthenium (III) complexes, K[Ru(Hedta)Cl]·2H2O (4) and [Ru(pic)3]·H2O (5). We assessed the physicochemical, adsorption, and photocatalytic properties of these composites with structural analyses (Raman spectroscopy, X-ray absorption (XAS), and SEM-EDX), confirming the stability of complexes within the PMMA matrix. Composites containing titanium(IV) compounds demonstrated notably higher photocatalytic efficiency than those with ruthenium(III) complexes. Based on activity profiles, composites were categorized into three types: (i) UV-light active (complexes (1) and (2)), (ii) visible-light active (complexes (4) and (5)), and (iii) dual-range active (complex (3)). The results highlight the strong potential of titanium(IV)–PMMA composites for UV-driven photocatalysis. Moreover, their activity can be extended to the visible range after structural modifications. Ruthenium(III)–PMMA composites, in turn, showed superior performance under visible light. Overall, PMMA composites with titanium(IV) or ruthenium(III) complexes demonstrate promising photocatalytic properties for applications using both UV and visible light ranges.
Nanoscale Ruthenium(III) Complexes with Bioactive Ligands: Structural, Colloidal, and Dual Antimicrobial–Cytotoxic Investigations
(Royal Society of Chemistry, 2025) Impert, Olga; Czerniecka, Natalia; Balińska, Natalia; Kubiak, Barbara; Kozakiewicz-Piekarz, Anna; Pryshchepa, Oleksandra; Pomastowski, Paweł; Ehlert, Michalina; Witwicki, Maciej; Pateda, Yogeswara Rao; Rakovský, Erik; Katafias, Anna; van Eldik Rudi
This study comprehensively analyses two new ruthenium(III) complexes, [RuIIICl4(Nic)2]−[(CH3)2NH2]+DMF, 1, and [RuIIICl2(3-HPA)2]−[3-HH2PA]+(EtOH)2, 2, (where Nic = nicotinic acid (vitamin B3), 3-HPA = anion of a 3-hydroxypicolinic acid), as potential antimicrobial agents, highlighting their physicochemical properties, nanoparticle formation, and cytotoxic activity. The complexes were fully characterised by a single crystal X-ray diffraction technique, Fourier-transform infrared, energy-dispersive X-ray, and electron paramagnetic resonance spectroscopies. The synthesis of micro- and nanoparticles (NPs) of these complexes was performed using the liquid anti-solvent crystallisation method. The formation of NPs was confirmed, and their sizes were determined using scanning electron microscopy and dynamic light scattering techniques.
The Debye-Scherrer technique, based on powder diffraction X-ray data, indicated the high crystallinity of the nanomaterials. Toxicity and morphological effects on L929 fibroblasts, hepatocellular carcinoma (Hep-G2) and human epithelial colorectal adenocarcinoma (Caco-2) cell lines of the complexes were assessed using the MTT assay and an inverted phase-contrast microscope, respectively. Complex 1 is a promising anti-cancer drug candidate targeting intestinal cancers, showing cytotoxicity against Caco- 2 cancer cells and no cytotoxicity against L929 fibroblast cells, while complex 2 is markedly cytotoxic.
The antibacterial activity of the complexes was assessed against methicillin-resistant Staphylococcus aureus (MRSA) and Klebsiella pneumoniae strains using the minimum inhibitory concentration (MIC) method. Complex 2 demonstrates superior bactericidal properties, achieving MIC values as low as 125 μg ml−1 for S. aureus, while complex 1 exhibits lower antimicrobial efficacy. The role of ligand composition in modulating bioactivity was examined.