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Brunčko M, Kirbiš P, Anžel I, Gusel L, Feizpour D, Irgolič T, Vuherer T. Evaluation of the Impact and Fracture Toughness of a Nanostructured Bainitic Steel with Low Retained Austenite Content. Materials (Basel) 2023; 16:2003. [PMID: 36903118 PMCID: PMC10004662 DOI: 10.3390/ma16052003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/19/2023] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
The impact and fracture toughness of a nanostructured, kinetically activated bainitic steel was determined using Standard methods. Prior to testing, the steel was quenched in oil and aged naturally for a period of 10 days in order to obtain a fully bainitic microstructure with a retained austenite content below 1%, resulting in a high hardness of 62HRC. The high hardness originated from the very fine microstructure of bainitic ferrite plates formed at low temperatures. It was determined that the impact toughness of the steel in the fully aged condition improved remarkably, whereas the fracture toughness was in line with expectations based on the extrapolated data available in the literature. This suggests that a very fine microstructure is most beneficial to rapid loading conditions, whereas material flaws such as coarse nitrides and non-metallic inclusions are the major limitation for obtaining a high fracture toughness.
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Affiliation(s)
- Mihael Brunčko
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Peter Kirbiš
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Ivan Anžel
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Leo Gusel
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Darja Feizpour
- Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana, Slovenia
| | - Tomaž Irgolič
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Tomaž Vuherer
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
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2
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Zemljič LF, Glaser TK, Plohl O, Anžel I, Šimat V, Čagalj M, Mežnar E, Malin V, Sterniša M, Možina SS. Biomass-Derived Plant Extracts in Macromolecular Chitosan Matrices as a Green Coating for PLA Films. J Funct Biomater 2022; 13:jfb13040228. [PMID: 36412869 PMCID: PMC9680410 DOI: 10.3390/jfb13040228] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
Due to the growing problem of food and packaging waste, environmental awareness, and customer requirements for food safety, there is a great need for the development of innovative and functional packaging. Among these developments, the concept of active packaging is at the forefront. The shortcoming in this area is that there is still a lack of multifunctional concepts, as well as green approaches. Therefore, this work focuses on the development of active chemical substances of natural origin applied as a coating on polylactic acid (PLA) films. Biopolymer chitosan and plant extracts rich in phenolic compounds (blackberry leaves-Rubus fruticosus, needles of prickly juniper-Juniperus oxycedrus) obtained from plant biomass from Southeastern Europe were selected in this work. In order to increase the effectiveness of individual substances and to introduce multifunctionality, they were combined in the form of different colloidal structural formulations. The plant extracts were embedded in chitosan biopolymer particles and dispersed in a macromolecular chitosan solution. In addition, a two-layer coating, the first of a macromolecular chitosan solution, and the second of a dispersion of the embedded extracts in chitosan particles, was applied to the PLA films as a novel approach. The success of the coatings was monitored by X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and the wettability was evaluated by contact angle measurements. Scanning electron microscopy SEM tracked the morphology and homogeneity of the coating. Antioxidation was studied by DPPH and ABTS spectrophotometric tests, and microbiological analysis of the films was performed according to the ISO 22196 Standard. Desorption of the coating from the PLA was monitored by reducing the elemental composition of the films themselves. The successful functionalization of PLA was demonstrated, while the XPS and ATR-FTIR analyses clearly showed the peaks of elemental composition of the extracts and chitosan on the PLA surface. Moreover, in all cases, the contact angle of the bilayer coatings decreased by more than 35-60% and contributed to the anti-fogging properties. The desorption experiments, due to decrease in the concentration of the specific typical element (nitrogen), indicated some migration of substances from the PLA's surface. The newly developed films also exhibited antioxidant properties, with antioxidant ABTS efficiencies ranging from 83.5 to 100% and a quite high inhibition of Gram-positive Staphylococcus aureus bacteria, averaging over 95%. The current functionalization of PLA simultaneously confers antifogging, antioxidant, and antimicrobial properties and drives the development of a biodegradable and environmentally friendly composite material using green chemistry principles.
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Affiliation(s)
- Lidija Fras Zemljič
- Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
- Correspondence: ; Tel.: +386-2-220-7909
| | - Tjaša Kraševac Glaser
- Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Olivija Plohl
- Laboratory for Characterization and Processing of Polymers, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Ivan Anžel
- Materials Transformation Laboratory, Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia
| | - Vida Šimat
- University Department of Marine Studies, University of Split, Ruđera Boškovića 37, 21000 Split, Croatia
| | - Martina Čagalj
- University Department of Marine Studies, University of Split, Ruđera Boškovića 37, 21000 Split, Croatia
| | - Eva Mežnar
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
| | - Valentina Malin
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
| | - Meta Sterniša
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
| | - Sonja Smole Možina
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
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Simić L, Rudolf R, Majerič P, Anžel I. Cast Microstructure of a Complex Concentrated Noble Alloy Ag 20Pd 20Pt 20Cu 20Ni 20. Materials (Basel) 2022; 15:ma15144788. [PMID: 35888254 PMCID: PMC9325168 DOI: 10.3390/ma15144788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 02/01/2023]
Abstract
A complex concentrated noble alloy (CCNA) of equiatomic composition (Ag20Pd20Pt20Cu20Ni20-20 at. %) was studied as a potential high-performance material. The equiatomic composition was used so that this alloy could be classified in the subgroup of high-entropy alloys (HEA). The alloy was prepared by induction melting at atmospheric pressure, using high purity elements. The degree of metastability of the cast state was estimated on the basis of changes in the microstructure during annealing at high temperatures in a protective atmosphere of argon. Characterisation of the metallographically prepared samples was performed using a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Observation shows that the microstructure of the CCNA is in a very metastable state and multiphase, consisting of a continuous base of dendritic solidification-a matrix with an interdendritic region without other microstructural components and complex spheres. A model of the probable flow of metastable solidification of the studied alloy was proposed, based on the separation of L-melts into L1 (rich in Ni) and L2 (rich in Ag). The phenomenon of liquid phase separation in the considered CCNA is based on the monotectic reaction in the Ag-Ni system.
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Affiliation(s)
- Lidija Simić
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (R.R.); (P.M.); (I.A.)
- Correspondence:
| | - Rebeka Rudolf
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (R.R.); (P.M.); (I.A.)
- Zlatarna Celje d.o.o., Kersnikova 19, 3000 Celje, Slovenia
| | - Peter Majerič
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (R.R.); (P.M.); (I.A.)
- Zlatarna Celje d.o.o., Kersnikova 19, 3000 Celje, Slovenia
| | - Ivan Anžel
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (R.R.); (P.M.); (I.A.)
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Jug A, Brunčko M, Rudolf R, Anžel I. Oxidation Behaviour of Microstructurally Highly Metastable Ag-La Alloy. Materials 2022; 15:ma15062295. [PMID: 35329748 PMCID: PMC8949107 DOI: 10.3390/ma15062295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/01/2022] [Accepted: 03/16/2022] [Indexed: 12/04/2022]
Abstract
A new silver-based alloy with 2 wt.% of lanthanum (La) was studied as a potential candidate for electric contact material. The alloy was prepared by rapid solidification, performed by the melt spinning technique. Microstructural examination of the rapidly solidified ribbons revealed very fine grains of αAg and intermetallic Ag5La particles, which appear in the volume of the grains, as well as on the grain boundaries. Rapid solidification enabled high microstructural refinement and provided a suitable starting microstructure for the subsequent internal oxidation, resulting in fine submicron-sized La2O3 oxide nanoparticle formation throughout the volume of the silver matrix (αAg). The resulting nanostructured Ag-La2O3 microstructure was characterised by high-resolution FESEM and STEM, both equipped with EDX. High-temperature internal oxidation of the rapidly solidified ribbons essentially changed the microstructure. Mostly homogeneously dispersed nano-sized La2O3 were formed within the grains, as well as on the grain boundaries. Three mechanisms of internal oxidation were identified: (i) the oxidation of La from the solid solution; (ii) partial dissolution of finer Ag5La particles before the internal oxidation front and oxidation of La from the solid solution; and (iii) direct oxidation of coarser Ag5La intermetallic particles.
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Tiyyagura HR, Majerič P, Bračič M, Anžel I, Rudolf R. Gold Inks for Inkjet Printing on Photo Paper: Complementary Characterisation. Nanomaterials (Basel) 2021; 11:599. [PMID: 33670845 PMCID: PMC7997470 DOI: 10.3390/nano11030599] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/19/2021] [Accepted: 02/24/2021] [Indexed: 11/17/2022]
Abstract
Nowadays, cost-effective, available, and flexible paper-based electronics play an essential role in the electronics industry. Herein, we present gold nanoparticles (AuNPs) as a potential raw material for gold inks in the future for such purposes. AuNPs in this research were synthesised using the ultrasonic spray pyrolysis (USP) technique from two precursors: gold (III) chloride tetrahydrate and gold (III) acetate. Synthesised AuNPs were collected in a suspension composed of deionised (D.I.) water and the stabiliser polyvinylpyrrolidone (PVP). AuNPs' suspensions were subjected to the rotavapor process to obtain gold inks with higher Au concentration (>300 ppm). ICP-MS measurements, the size and shape of AuNPs, ζ-potential, Ultraviolet-visible (UV-Vis) spectrophotometry measurements, and scanning electron microscop y (SEM) of gold inks were carried out in order to find the optimal printing parameters. In the final stage, the optical contact angle measurements were performed using a set of polar to non-polar liquids, allowing for the determination of the surface free energy of gold inks. Inkjet printing of gold inks as defined stripes on photo paper were tested, based on the characterisation results.
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Affiliation(s)
- Hanuma Reddy Tiyyagura
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (H.R.T.); (P.M.); (M.B.); (I.A.)
- Zlatarna Celje d.o.o., Kersnikova ulica 19, 3000 Celje, Slovenia
| | - Peter Majerič
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (H.R.T.); (P.M.); (M.B.); (I.A.)
- Zlatarna Celje d.o.o., Kersnikova ulica 19, 3000 Celje, Slovenia
| | - Matej Bračič
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (H.R.T.); (P.M.); (M.B.); (I.A.)
| | - Ivan Anžel
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (H.R.T.); (P.M.); (M.B.); (I.A.)
| | - Rebeka Rudolf
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (H.R.T.); (P.M.); (M.B.); (I.A.)
- Zlatarna Celje d.o.o., Kersnikova ulica 19, 3000 Celje, Slovenia
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Rudolf R, Popović D, Tomić S, Bobovnik R, Lazić V, Majerič P, Anžel I, Čolić M. Microstructure Characterisation and Identification of the Mechanical and Functional Properties of a New PMMA-ZnO Composite. Materials (Basel) 2020; 13:ma13122717. [PMID: 32549247 PMCID: PMC7344969 DOI: 10.3390/ma13122717] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/04/2020] [Accepted: 06/08/2020] [Indexed: 11/16/2022]
Abstract
In this research work, we synthesised poly(methyl methacrylate) (PMMA) enriched with 2 wt.% zinc oxide nanoparticles (ZnO) through conventional heat polymerisation and characterised its microstructure. It was found that the distribution of ZnO nanoparticles was homogeneous through the volume of the PMMA. The mechanical testing of the PMMA-ZnO composite primarily included the determination of the compressive properties on real dentures, while density measurements were performed using a pycnometer. The testing of functional properties involved the identification of the colour of the new PMMA-ZnO composite, where pure PMMA acted as a control. In the second step, the PMMA-ZnO cytotoxicity assays were measured in vitro, which were shown to be similar to the control PMMA. Based on this, it could be concluded that the newly formed PMMA-ZnO composite did not induce direct or indirect cytotoxic effects in L929 cell cultures; therefore, according to ISO/DIN 10993-5:2009, this composite was categorised as non-cytotoxic.
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Affiliation(s)
- Rebeka Rudolf
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (P.M.); (I.A.)
- Zlatarna Celje d. o. o., Kersnikova 19, 3000 Celje, Slovenia
- Correspondence:
| | - Danica Popović
- School of Dental Medicine, University of Belgrade, dr. Subotića 8, 11000 Belgrade, Serbia; (D.P.); (V.L.)
| | - Sergej Tomić
- Institute for the Application of Nuclear Energy, University of Belgrade, Banatska 31b, 11000 Belgrade, Serbia;
| | - Rajko Bobovnik
- Faculty of Polymer Technology, Ozare 19, 2380 Slovenj Gradec, Slovenia;
| | - Vojkan Lazić
- School of Dental Medicine, University of Belgrade, dr. Subotića 8, 11000 Belgrade, Serbia; (D.P.); (V.L.)
| | - Peter Majerič
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (P.M.); (I.A.)
- Zlatarna Celje d. o. o., Kersnikova 19, 3000 Celje, Slovenia
| | - Ivan Anžel
- Faculty of Mechanical Engineering, University of Maribor, Smetanova ulica 17, 2000 Maribor, Slovenia; (P.M.); (I.A.)
| | - Miodrag Čolić
- Military Medical Academy Belgrade, Crnotravska 17, 11002 Beograd, Serbia;
- Medical Faculty in Foca, University of East Sarajevo, Studentska 5, 73300 Foca, Republic of Srpska
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Kirbiš P, Anžel I, Rudolf R, Brunčko M. Novel Approach of Nanostructured Bainitic Steels' Production with Improved Toughness and Strength. Materials (Basel) 2020; 13:ma13051220. [PMID: 32182765 PMCID: PMC7085109 DOI: 10.3390/ma13051220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/26/2020] [Accepted: 02/28/2020] [Indexed: 06/10/2023]
Abstract
The tendencies of development within the field of engineering materials show a persistent trend towards the increase of strength and toughness. This pressure is particularly pronounced in the field of steels, since they compete with light alloys and composite materials in many applications. The improvement of steels' mechanical properties is sought to be achieved with the formation of exceptionally fine microstructures ranging well into the nanoscale, which enable a substantial increase in strength without being detrimental to toughness. The preferred route by which such a structure can be produced is not by applying the external plastic deformation, but by controlling the phase transformation from austenite into ferrite at low temperatures. The formation of bainite in steels at temperatures lower than about 200 °C enables the obtainment of the bulk nanostructured materials purely by heat treatment. This offers the advantages of high productivity, as well as few constraints in regard to the shape and size of the workpiece when compared with other methods for the production of nanostructured metals. The development of novel bainitic steels was based on high Si or high Al alloys. These groups of steels distinguish a very fine microstructure, comprised predominantly of bainitic ferrite plates, and a small fraction of retained austenite, as well as carbides. The very fine structure, within which the thickness of individual bainitic ferrite plates can be as thin as 5 nm, is obtained purely by quenching and natural ageing, without the use of isothermal transformation, which is characteristic for most bainitic steels. By virtue of their fine structure and low retained austenite content, this group of steels can develop a very high hardness of up to 65 HRC, while retaining a considerable level of impact toughness. The mechanical properties were evaluated by hardness measurements, impact testing of notched and unnotched specimens, as well as compression and tensile tests. Additionally, the steels' microstructures were characterised using light microscopy, field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). The obtained results confirmed that the strong refinement of the microstructural elements in the steels results in a combination of extremely high strength and very good toughness.
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Affiliation(s)
- Peter Kirbiš
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia; (I.A.); (R.R.); (M.B.)
- SIJ Metal Ravne d.o.o., Koroška cesta 14, SI-2390 Ravne na Koroškem, Slovenia
| | - Ivan Anžel
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia; (I.A.); (R.R.); (M.B.)
| | - Rebeka Rudolf
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia; (I.A.); (R.R.); (M.B.)
| | - Mihael Brunčko
- Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, SI-2000 Maribor, Slovenia; (I.A.); (R.R.); (M.B.)
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Bekić M, Tomić S, Rudolf R, Milanović M, Vučević D, Anžel I, Čolić M. The Effect of Stabilisation Agents on the Immunomodulatory Properties of Gold Nanoparticles Obtained by Ultrasonic Spray Pyrolysis. Materials (Basel) 2019; 12:ma12244121. [PMID: 31835366 PMCID: PMC6947030 DOI: 10.3390/ma12244121] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/04/2019] [Accepted: 12/06/2019] [Indexed: 12/31/2022]
Abstract
Gold nanoparticles (GNPs) have been investigated extensively as drug carriers in tumour immunotherapy in combination with photothermal therapy. For this purpose, GNPs should be stabilised in biological fluids. The goal of this study was to examine how stabilisation agents influence cytotoxicity and immune response in vitro. Spherical GNPs, 20 nm in size, were prepared by ultrasonic spray pyrolysis (USP). Three types of stabilising agents were used: sodium citrate (SC), polyvinyl-pyrrolidone (PVP), and poly-ethylene glycol (PEG). Pristine, non-stabilised GNPs were used as a control. The culture models were mouse L929 cells, B16F10 melanoma cells and human peripheral blood mononuclear cells (PBMNCs), obtained from healthy donors. Control SC- and PEG-GNPs were non-cytotoxic at concentrations (range 1–100 µg/mL), in contrast to PVP-GNPs, which were cytotoxic at higher concentrations. Control GNPs inhibited the production of IFN-ϒ slightly, and augmented the production of IL-10 by PHA-stimulated PBMNC cultures. PEG-GNPs inhibited the production of pro-inflammatory cytokines (IL-1, IL-6, IL-8, TNF-α) and Th1-related cytokines (IFN-ϒ and IL-12p70), and increased the production of Th2 cytokines (IL-4 and IL-5). SC-PEG inhibited the production of IL-8 and IL-17A. In contrast, PVP-GNPs stimulated the production of pro-inflammatory cytokines, Th1 cytokines, and IL-17A, but also IL-10. When uptake of GNPs by monocytes/macrophages in PBMNC cultures was analysed, the ingestion of PEG- GNPs was significantly lower compared to SC- and PVP-GNPs. In conclusion, stabilisation agents modulate biocompatibility and immune response significantly, so their adequate choice for preparation of GNPs is an important factor when considering the use of GNPs for application in vivo.
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Affiliation(s)
- Marina Bekić
- Institute for Application of Nuclear Energy, University of Belgrade, 11000 Belgrade, Serbia; (M.B.); (S.T.)
| | - Sergej Tomić
- Institute for Application of Nuclear Energy, University of Belgrade, 11000 Belgrade, Serbia; (M.B.); (S.T.)
| | - Rebeka Rudolf
- Faculty for Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (R.R.); (I.A.)
| | - Marijana Milanović
- Medical Faculty of the Military Medical Academy, University of Defense in Belgrade, 11000 Belgrade, Serbia; (M.M.); (D.V.)
| | - Dragana Vučević
- Medical Faculty of the Military Medical Academy, University of Defense in Belgrade, 11000 Belgrade, Serbia; (M.M.); (D.V.)
| | - Ivan Anžel
- Faculty for Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (R.R.); (I.A.)
| | - Miodrag Čolić
- Institute for Application of Nuclear Energy, University of Belgrade, 11000 Belgrade, Serbia; (M.B.); (S.T.)
- Medical Faculty of the Military Medical Academy, University of Defense in Belgrade, 11000 Belgrade, Serbia; (M.M.); (D.V.)
- Medical Faculty Foča, University of East Sarajevo, 73300 Foča, Republic of Srpska, Bosnia and Hercegovina
- Correspondence: ; Tel.: +381-11-219-3194
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Kožuh S, Gojić M, Ivanić I, Holjevac Grgurić T, Kosec B, Anžel I. The Effect of Heat Treatment on the Microstructure and Mechanical Properties of Cu-Al-Mn Shape Memory Alloy. Kem Ind 2018. [DOI: 10.15255/kui.2017.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Tomić S, Đokić J, Vasilijić S, Ogrinc N, Rudolf R, Pelicon P, Vučević D, Milosavljević P, Janković S, Anžel I, Rajković J, Rupnik MS, Friedrich B, Čolić M. Size-dependent effects of gold nanoparticles uptake on maturation and antitumor functions of human dendritic cells in vitro. PLoS One 2014; 9:e96584. [PMID: 24802102 PMCID: PMC4011871 DOI: 10.1371/journal.pone.0096584] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 04/08/2014] [Indexed: 12/23/2022] Open
Abstract
Gold nanoparticles (GNPs) are claimed as outstanding biomedical tools for cancer diagnostics and photo-thermal therapy, but without enough evidence on their potentially adverse immunological effects. Using a model of human dendritic cells (DCs), we showed that 10 nm- and 50 nm-sized GNPs (GNP10 and GNP50, respectively) were internalized predominantly via dynamin-dependent mechanisms, and they both impaired LPS-induced maturation and allostimulatory capacity of DCs, although the effect of GNP10 was more prominent. However, GNP10 inhibited LPS-induced production of IL-12p70 by DCs, and potentiated their Th2 polarization capacity, while GNP50 promoted Th17 polarization. Such effects of GNP10 correlated with a stronger inhibition of LPS-induced changes in Ca2+ oscillations, their higher number per DC, and more frequent extra-endosomal localization, as judged by live-cell imaging, proton, and electron microscopy, respectively. Even when released from heat-killed necrotic HEp-2 cells, GNP10 inhibited the necrotic tumor cell-induced maturation and functions of DCs, potentiated their Th2/Th17 polarization capacity, and thus, impaired the DCs' capacity to induce T cell-mediated anti-tumor cytotoxicity in vitro. Therefore, GNP10 could potentially induce more adverse DC-mediated immunological effects, compared to GNP50.
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Affiliation(s)
- Sergej Tomić
- Medical Faculty of the Military Medical Academy, University of Defense, Belgrade, Serbia
- Institute for Medical Research of the Military Medical Academy, University of Defense, Belgrade, Serbia
| | - Jelena Đokić
- Medical Faculty of the Military Medical Academy, University of Defense, Belgrade, Serbia
| | - Saša Vasilijić
- Medical Faculty of the Military Medical Academy, University of Defense, Belgrade, Serbia
- Institute for Medical Research of the Military Medical Academy, University of Defense, Belgrade, Serbia
| | - Nina Ogrinc
- Microanalytical Center, Jožef Stefan Institute, Ljubljana, Slovenia
- LOTRIČ Metrology, Selca, Slovenia
| | - Rebeka Rudolf
- Faculty of Mechanical Engineering, University of Maribor, Maribor, Slovenia
- Zlatarna Celje d.d., Celje, Slovenia
| | - Primož Pelicon
- Microanalytical Center, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Dragana Vučević
- Medical Faculty of the Military Medical Academy, University of Defense, Belgrade, Serbia
- Institute for Medical Research of the Military Medical Academy, University of Defense, Belgrade, Serbia
| | - Petar Milosavljević
- Institute for Medical Research of the Military Medical Academy, University of Defense, Belgrade, Serbia
| | | | - Ivan Anžel
- Faculty of Mechanical Engineering, University of Maribor, Maribor, Slovenia
| | | | | | - Bernd Friedrich
- Department of Process Metallurgy and Metal Recycling, Rheinisch-Westfälische Technische Hochschule, Aachen University, Aachen, Germany
| | - Miodrag Čolić
- Medical Faculty of the Military Medical Academy, University of Defense, Belgrade, Serbia
- Medical Faculty, University of Niš, Niš, Serbia
- * E-mail:
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Đokić J, Rudolf R, Tomić S, Stopić S, Friedrich B, Budič B, Anžel I, Čolić M. Immunomodulatory Properties of Nanoparticles Obtained by Ultrasonic Spray Pirolysis from Gold Scrap. J Biomed Nanotechnol 2012. [DOI: 10.1166/jbn.2012.1405] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Tomić S, Rudolf R, Brunčko M, Anžel I, Savić V, Colić M, Čolić M. Response of monocyte-derived dendritic cells to rapidly solidified nickel-titanium ribbons with shape memory properties. Eur Cell Mater 2012; 23:58-80. [PMID: 22287114 DOI: 10.22203/ecm.v023a05] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Ni-Ti Shape Memory Alloys (SMAs) have attracted considerable attention as biomaterials for medical devices. However, the biocompatibility of Ni-Ti SMAs is often unsatisfactory due to their poor surface structure. Here we prepared Rapidly Solidified (RS) Ni-Ti SMA ribbons by melt-spinning and their surface was characterised by Auger-electron spectroscopy, X-ray photoelectron spectrometry and scanning electron microscopy. The biocompatibility of the produced ribbons and their immunomodulatory properties were studied on human monocyte-derived dendritic cells (MoDCs). We showed that melt-spinning of Ni-Ti SMAs can form a thin homogenous oxide layer, which improves their corrosion resistance and subsequent toxicity to MoDCs. Ni-Ti RS ribbons stimulated the maturation of MoDCs, as detected by changes in the cells' morphology and increased expression of HLA-DR, CD86, CD40 and CD83 molecules. However, Ni-Ti RS ribbons enhanced the tolerogenic properties of immature MoDCs, which produced higher levels of IL-10 and IL-27, driving the differentiation of IL-10- and TGF-β-producing CD4+T cells. On the other hand, in the presence of lipopolysaccharide, an important pro-inflammatory biomolecule, Ni-Ti RS ribbons enhanced the allostimulatory and Th1 polarising capacity of MoDCs, whereas the production of Th2 and Th17 cytokines was down-regulated. In conclusion, Ni-Ti RS ribbons possess substantial immunomodulatory properties on MoDCs. These findings might be clinically relevant, because implanted Ni-Ti SMA devices can induce both desired and adverse effects on the immune system, depending on the microenvironmental stimuli.
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Affiliation(s)
- S Tomić
- Military Medical Academy, Crnotravska 17, 11000 Belgrade, Serbia.
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Rudolf R, Friedrich B, Stopić S, Anžel I, Tomić S, Čolić M. Cytotoxicity of gold nanoparticles prepared by ultrasonic spray pyrolysis. J Biomater Appl 2010; 26:595-612. [PMID: 20819920 DOI: 10.1177/0885328210377536] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this work was to study the cytotoxicity of different fractions of gold nanoparticles prepared by ultrasonic spray pyrolysis from gold scrap. The target cells were rat thymocytes, as a type of nonproliferating cells, and L929 mouse fibroblasts, as a type of continuous proliferating cells. Fractions 1 and 2, composed of pure gold nanoparticles, as determined by scanning electron microscopy with a combination of energy dispersive X-ray analysis, were nontoxic for thymocytes, but reduced moderately the proliferative activity of L929 cells. The inhibitory effect of fraction 2, containing particles smaller in size than fraction 1, was stronger. Fraction 3, composed of Au and up to 3% Cu was noncytotoxic for thymocytes, but was cytotoxic for L929 cells. Fraction 4, composed of Au and Ag nanoparticles, and fraction 5, composed of Au together with Cu, Ni, Zn, Fe, and In were cytotoxic for both thymocytes and L929 cells. These results suggest that USP enables the synthesis of pure gold nanoparticles with controlled size, even from gold scrap. However, microstructural analyses and biocompatibility testing are necessary for their proper selection from more cytotoxic gold nanoparticles, contaminated with other elements of gold alloys.
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Affiliation(s)
- R Rudolf
- Faculty of Mechanical Engineering, University of Maribor Smetanova 17, SI- 2000 Maribor, Slovenia.
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Čolić M, Rudolf R, Stamenković D, Anžel I, Vučević D, Jenko M, Lazić V, Lojen G. Relationship between microstructure, cytotoxicity and corrosion properties of a Cu-Al-Ni shape memory alloy. Acta Biomater 2010; 6:308-17. [PMID: 19540942 DOI: 10.1016/j.actbio.2009.06.027] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 06/12/2009] [Accepted: 06/16/2009] [Indexed: 10/20/2022]
Abstract
Cu-Al-Ni shape memory alloys (SMAs) have been investigated as materials for medical devices, but their biomedical application is still limited. The aim of this work was to compare the microstructure, corrosion and cytotoxicity in vitro of a Cu-Al-Ni SMA. Rapidly solidified (RS) thin ribbons, manufactured via melt spinning, were used for the tests. The control alloy was a permanent mould casting of the same composition, but without shape memory effect. The results show that RS ribbons are significantly more resistant to corrosion compared with the control alloy, as judged by the lesser release of Cu and Ni into the conditioning medium. These results correlate with the finding that RS ribbons were not cytotoxic to L929 mouse fibroblasts and rat thymocytes. In addition, the RS ribbon conditioning medium inhibited cellular proliferation and IL-2 production by activated rat splenocytes to a much lesser extent. The inhibitory effects were almost completely abolished by conditioning the RS ribbons in culture medium for 4 weeks. Microstructural analysis showed that RS ribbons are martensitic, with boron particles as a minor phase. In contrast, the control Cu-Al-Ni alloy had a complex multiphase microstructure. Examination of the alloy surfaces after conditioning by energy dispersive X-ray and Auger electron spectroscopy showed the formation of Cu and Al oxide layers and confirmed that the metals in RS ribbons are less susceptible to oxidation and corrosion compared with the control alloy. In conclusion, these results suggest that rapid solidification significantly improves the corrosion stability and biocompatibility in vitro of Cu-Al-Ni SMA ribbons.
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Abstract
Cu—Al—Ni shape memory alloys (SMAs) have been investigated as materials for medical devices, but little is known about their biocompatibility. The aim of this work was to study the response of rat peritoneal macrophages (PMØ) to a Cu—Al—Ni SMA in vitro, by measuring the functional activity of mitochondria, necrosis, apoptosis, and production of proinflammatory cytokines. Rapidly solidified (RS) thin ribbons were used for the tests. The control alloy was a permanent mold casting of the same composition, but without the shape memory effect. Our results showed that the control alloy was severely cytotoxic, whereas RS ribbons induced neither necrosis nor apoptosis of PMØ. These findings correlated with the data that RS ribbons are significantly more resistant to corrosion compared to the control alloy, as judged by the lesser release of Cu and Ni in the conditioning medium. However, the ribbons generated intracellular reactive oxygen species and upregulated the production of IL-6 by PMØ. These effects were almost completely abolished by conditioning the RS ribbons for 5 weeks. In conclusion, RS significantly improves the corrosion stability and biocompatibility of Cu—Al—Ni SMA. The biocompatibility of this functional material could be additionally enhanced by conditioning the ribbons in cell culture medium.
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Affiliation(s)
- Miodrag Čolić
- Institute of Medical Research, MMA, Crnotravska 17, 11002 Belgrade, Serbia,
| | - Sergej Tomić
- Institute of Medical Research, MMA, Crnotravska 17, 11002 Belgrade, Serbia
| | - Rebeka Rudolf
- University of Maribor, Faculty of Mechanical Engineering Smetanova 17, SI- 2000 Maribor, Slovenia
| | - Ivan Anžel
- University of Maribor, Faculty of Mechanical Engineering Smetanova 17, SI- 2000 Maribor, Slovenia
| | - Gorazd Lojen
- University of Maribor, Faculty of Mechanical Engineering Smetanova 17, SI- 2000 Maribor, Slovenia
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