Publications by authors named "Zdenka Lukacova Bujnakova"

Binary AsSe alloys from the border of a glass-forming region (65 < < 70) subjected to nanomilling in dry and dry-wet modes are characterized by the XRPD, micro-Raman scattering (micro-RS) and revised positron annihilation lifetime (PAL) methods complemented by a disproportionality analysis using the quantum-chemical cluster modeling approach. These alloys are examined with respect to tetra-arsenic biselenide AsSe stoichiometry, realized in glassy g-AsSe, glassy-crystalline g/c-AsSe and glassy-crystalline g/c-AsSe. From the XRPD results, the number of rhombohedral As and cubic arsenolite AsO phases in As-Se alloys increases after nanomilling, especially in the wet mode realized in a PVP water solution.

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  • * The composite NPs work by triggering specific cellular pathways leading to cell cycle arrest, activation of apoptosis, and reducing stem cell-like characteristics in MM cells, making them potentially more effective in treatment.
  • * Both formulations of NPs exhibited enhanced effects when combined with established anti-MM drugs like dexamethasone and bortezomib, suggesting important implications for improving clinical outcomes in MM therapy.
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Polyamorphic transformations driven by high-energy mechanical ball milling (nanomilling) are recognized in a melt-quenched glassy alloy of tetra-arsenic triselenide (AsSe). We employed XRPD analysis complemented by thermophysical heat-transfer and micro-Raman spectroscopy studies. A straightforward interpretation of the medium-range structural response to milling-driven reamorphization is developed within a modified microcrystalline model by treating diffuse peak-halos in the XRPD patterns of this alloy as a superposition of the Bragg-diffraction contribution from inter-planar correlations, which are supplemented by the Ehrenfest-diffraction contribution from inter-atomic and/or inter-molecular correlations related to derivatives of thioarsenide AsSe molecules, mainly dimorphite-type AsSe ones.

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Multifunctional nanocomposites from an equimolar AsS/FeO cut section have been successfully fabricated from coarse-grained bulky counterparts, employing two-step mechanochemical processing in a high-energy mill operational in dry- and wet-milling modes (in an aqueous solution of Poloxamer 407 acting as a surfactant). As was inferred from the X-ray diffraction analysis, these surfactant-free and surfactant-capped nanocomposites are -AsS-bearing nanocrystalline-amorphous substances supplemented by an iso-compositional amorphous phase (a-AsS), both principal constituents (monoclinic -AsS and cubic FeO) being core-shell structured and enriched after wet milling by contamination products (such as nanocrystalline-amorphous zirconia), suppressing their nanocrystalline behavior. The fluorescence and magnetic properties of these nanocomposites are intricate, being tuned by the sizes of the nanoparticles and their interfaces, dependent on storage after nanocomposite fabrication.

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  • The paper investigates the preparation and characterization of ZnS nanoparticles bioconjugated with bovine serum albumin, leading to a stable nanosuspension with specific particle size and zeta potential.
  • It explores the interactions between ZnS and albumin through fluorescence techniques, identifying key parameters like quenching and binding constants, and highlighting that tryptophan is more closely situated to the binding site than tyrosine.
  • The study also assesses the cellular effects of the nanosuspension on multiple myeloma cells, showing its nontoxic potential for drug delivery, while examining structural changes in albumin and conducting thermal and stability analyses.
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  • This study focuses on the interaction between arsenic sulfide (AsS) nanoparticles and bovine serum albumin, which is a key protein in the body, investigating how they bond and affect each other.
  • The research includes detailed analysis of how the presence of AsS nanoparticles impacts the fluorescence of amino acids like tyrosine and tryptophan, revealing that tryptophan is more significantly quenched, suggesting a closer binding.
  • Lastly, the study tests the potential anti-tumor effects of the albumin-AsS system on multiple myeloma cell lines, providing insights into its effectiveness in cancer treatment.
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Copper, antimony and sulfur in elemental form were applied for one-pot solid-state mechanochemical synthesis of skinnerite (CuSbS) in a laboratory mill and an industrial mill. This synthesis was completed after 30 min of milling in the laboratory mill and 120 min in the industrial mill, as corroborated by X-ray diffraction. XRD analysis confirmed the presence of pure monoclinic skinnerite prepared in the laboratory mill and around 76% monoclinic skinnerite, with the secondary phases famatinite (CuSbS; 15%), and tetrahedrite (CuSbS; 8%), synthesized in the industrial mill.

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  • * This study tested three types of nanocomposites (3NPs) that showed decreased survival rates in MM cells and induced cell death through various mechanisms, including apoptosis and cell cycle regulation.
  • * The 3NPs remained effective against MM cells even in protective bone marrow environments and demonstrated strong synergistic effects when combined with existing drugs, highlighting their potential for future treatment strategies.
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The biocompatible nanosuspension of CuS nanoparticles (NPs) using bovine serum albumin (BSA) as a capping agent was prepared using a two-stage mechanochemical approach. CuS NPs were firstly synthetized by a high-energy planetary ball milling in 15 min by milling elemental precursors. The stability of nanoparticles in the simulated body fluids was studied, revealing zero copper concentration in the leachates, except simulated lung fluid (SLF, 0.

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The possibilities surrounding positronics, a versatile noninvasive tool employing annihilating positrons to probe atomic-deficient sub-nanometric imperfections in a condensed matter, are analyzed in application to glassy arsenoselenides g-AsSe (0 < x < 65), subjected to dry and wet (in 0.5% PVP water solution) nanomilling. A preliminary analysis was performed within a modified two-state simple trapping model (STM), assuming slight contributions from bound positron-electron (Ps, positronium) states.

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The impact of high-energy milling on glassy arsenic monoselenide g-AsSe is studied with X-ray diffraction applied to diffuse peak-halos proper to intermediate- and extended-range ordering revealed in first and second sharp diffraction peaks (FSDP and SSDP). A straightforward interpretation of this effect is developed within the modified microcrystalline approach, treating "amorphous" halos as a superposition of the broadened Bragg diffraction reflexes from remnants of some inter-planar correlations, supplemented by the Ehrenfest diffraction reflexes from most prominent inter-molecular and inter-atomic correlations belonging to these quasi-crystalline remnants. Under nanomilling, the cage-like AsSe molecules are merely destroyed in g-AsSe, facilitating a more polymerized chain-like network.

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This study shows mechanochemical synthesis as an alternative method to the traditional green synthesis of silver nanoparticles in a comparative manner by comparing the products obtained using both methodologies and different characterization methods. As a silver precursor, the most commonly used silver nitrate was applied and the easily accessible lavender ( L.) plant was used as a reducing agent.

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A green synthetic route for the production of silver nanoparticles (AgNPs) using five different aqueous plant extracts, namely, , , , and , was investigated in this study. The present work demonstrates the influence of plant extract composition (antioxidant and total phenolic content) on the size and morphology of the produced AgNPs. The biosynthetic procedure was rapid and simple and was easily monitored via colour changes and ultraviolet and visible (UV-Vis) spectroscopy.

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  • Researchers created CuInSe/ZnS nanocomposites using a two-step mechanochemical process that involved co-milling different precursors in a planetary mill to form the nanocrystals.
  • The synthesized nanoparticles were then stabilized using sodium dodecyl sulfate (SDS), resulting in stable nanosuspensions that maintained their stability for up to 20 weeks.
  • Both nanocomposite suspensions demonstrated the ability to effectively reduce the viability of multiple myeloma cell lines, indicating their potential use in cancer treatment.
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A combination of solid-state mechanochemical and green approaches for the synthesis of silver nanoparticles (AgNPs) is explored in this study. L. (SER), L.

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In this study, CuInS₂/ZnS nanocrystals were synthesized by a two-step mechanochemical synthesis for the first time. In the first step, tetragonal CuInS₂ was prepared from copper, indium and sulphur precursors. The obtained CuInS₂ was further co-milled with zinc acetate dihydrate and sodium sulphide nonahydrate as precursors for cubic ZnS.

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