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Publication in Inorganic Chemistry

Journal cover15. December 2020

Publication entitled "Reversible Spin-State Switching and Tuning of Nuclearity and Dimensionality via Nonlinear Pseudohalides in Cobalt(II) Complexes" (authors: S. Ghosh, S. Kamilya, M. Rouzières, R. Herchel, S. Mehta, A. Mondal ) has been published in the chemistry journal Inorganic Chemistry.

Herein, we report on investigations of magnetic, spectroscopic and electrochemical properties of two Co(II) coordination compounds with N,N-di-tert-butyl-2,11-diaza[3,3](2,6)pyridinophane macrocyclic ligand. Complex 1 exhibits a high-spin (S = 3/2) state of cobalt(II) with a large magnetic anisotropy. Interestingly, complex 2 exhibits reversible spin-state switching (T1/2 = 321 K).

Publication in Dalton Transactions

Journal cover29. October 2020

Publication entitled "From solid state to in vitro anticancer activity of copper(II) compounds with electronically-modulated NNO Schiff base ligands" (authors: L. Rigamonti, F. Reginato, E. Ferrari, L. Pigani, L. Gigli, N. Demitri, P. Kopel, B. Tesarova, Z. Heger) has been published in the chemistry journal Dalton Transactions.

The copper(II) complexes of general formula [Cu(GL)(Cl)] (13, G = OMe, H and NO2, respectively), bearing tridentate Schiff base ligands (GL) and a chloride as a fourth labile one, are here reported. The Schiff bases derive from the monocondensation of ethylenediamine and substituted salicylaldehyde, where the electronic properties are modulated by the releasing or withdrawing power of the G group. The compounds were structurally characterized through single crystal Synchrotron X-ray diffraction experiments in the solid state. In vitro tests on cell viability were conducted on malignant cell lines. All compounds were capable of formation of intracellular reactive oxygen species and DNA intercalation. This is especially effective for 3 (NO2), which revealed the highest anticancer activity against malignant triple-negative breast cancer MDA-MB-231 cells.

Publication in Nanomaterials

29. October 2020

Publication entitled "Synergistic Effect of Chitosan and Selenium Nanoparticles on Biodegradation and Antibacterial Properties of Collagenous Scaffolds Designed for Infected Burn Wounds" (authors: J. Dorazilová, J. Muchová, K. Šmerková, S. Kočiová, P. Diviš, P. Kopel, R. Veselý, V. Pavliňáková, V. Adam, L. Vojtová) has been published in the journal Nanomaterials.

A highly porous scaffold is a desirable outcome in the field of tissue engineering. The porous structure mediates water-retaining properties that ensure good nutrient transportation as well as creates a suitable environment for cells. In this study, porous antibacterial collagenous scaffolds containing chitosan and selenium nanoparticles (SeNPs) as antibacterial agents were studied. The addition of antibacterial agents increased the application potential of the material for infected and chronic wounds. The morphology, swelling, biodegradation, and antibacterial activity of collagen-based scaffolds were characterized systematically to investigate the overall impact of the antibacterial additives. The additives visibly influenced the morphology, water-retaining properties as well as the stability of the materials in the presence of collagenase enzymes. Even at concentrations as low as 5 ppm of SeNPs, modified polymeric scaffolds showed considerable inhibition activity towards Gram-positive bacterial strains such as Staphylococcus aureus and methicillin-resistant S. aureus and S. epidermidis.

Publication in Dalton Transactions

10. September 2020

Publication entitled " Co(ii)-Based single-ion magnets with 1,1′-ferrocenediyl-bis(diphenylphosphine) metalloligands" (authors: J. Hrubý, D. Dvořák, L. Squillantini, M. Mannini, J. van Slageren, R. Herchel, I. Nemec, P. Neugebauer ) has been published in the chemistry journal Dalton Transactions.

Herein, we report on investigations of magnetic and spectroscopic properties of three heterobimetallic Fe(II)–Co(II) coordination compounds based on the tetracoordinate {CoP2X2} core encapsulated by dppf metalloligand, where X = Cl (1), Br (2), I (3), dppf = 1,1′-ferrocenediyl -bis(diphenylphosphine). The analysis of static magnetic data has revealed the presence of axial magnetic anisotropy in compounds (1) and (2) and this was further confirmed by high-frequency electron spin resonance (HF-ESR) spectroscopy. Dynamic magnetic data confirmed that (1) and (2) behave as field-induced Single-Ion Magnets (SIMs). Together with bulk studies, we have also tested the possibility of depositing (2) as thick films on Au(111), glass, and polymeric acetate by drop-casting as well as thermal sublimation, a key aspect for the development of future devices embedding these magnetic objects.

Endowment Fund of Palacký University supported our student

17. july 2020

Ph.D. student of Inorganic Chemie Mgr. Marie Pražáková received a finantial support from Endowment fung of Palacky University.

Mgr. Marie Pražáková, a first-year doctoral student in Inorganic Chemistry, succeeded and received a financial support from the UP Endowment Fund, which will be very beneficial for solving her research project called Research of Contrast Agents for MRI (Magnetic Resonance Imaging).

More details can be found on the webpage of the Faculty of Science or UP Endowment Fund.

Congratulations to Marie and we wish her much success in solving the project.

(Mgr. Pražáková second from the right)

Publication in Dalton Transactions

8. july 2020

Publication entitled "Late first-row transition metal complexes of a 17-membered piperazine-based macrocyclic ligand: structures and magnetism." (authors: E. Zahradníková, R. Herchel, I. Šalitroš, I. Císařová, B. Drahoš) has been published in the chemistry journal Dalton Transactions.

The 17-membered piperazine-based macrocyclic ligand LdiProp (1,5,13,17,22-pentaazatricyclo[15.2.2.17,11]docosa-7,9,11(22)-triene) was resynthesized in high yield with help of linear pump. Its Mn(II), Fe(II), Co(II) and Ni(II) complexes of general formula [MnLdiProp(ClO4)2] (1), [FeLdiProp(CH3CN)](ClO4)2 (2), [CoLdiProp(CH3CN)](ClO4)2 (3), [NiLdiProp](ClO4)2 (4) were prepared and thoroughly characterized. X-ray diffraction analysis confirmed that Mn(II) complex 1 has capped trigonal prismatic geometry with coordination number seven, Fe(II) and Co(II) complexes 2 and 3 are trigonal prismatic with coordination number six and Ni(II) complex 4 has square pyramidal geometry with coordination number five. The decrease of coordination number is accompanied by a shortening of M–N distances and an increase of torsion of piperazine ring from the equatorial plane. Magnetic measurement reveal moderate for 4 and rather large magnetic anisotropy for 2 and 3 (axial zero-field splitting parameter D(Ni) = 9.0 cm–1, D(Fe) = –14.4 cm–1, D(Co) = –25.8 cm–1, together with rather high rhombicity). Co(II) complex 3 behaves as field-induced SMM with a combination of Raman and direct or Orbach and direct relaxation mechanisms. Obtained magnetic data were extensively supported by theoretical CASSCF calculations. The flexibility and rather large 17-membered macrocyclic cavity of ligand LdiProp could be responsible for the variation of coordination numbers and geometries for investigated late-first row transition metals.