Search

Titanium and its alloys are the most used biomaterials for orthopedic and dental applications. However, up to 10% of these medical devices still fail, mostly due to implant loosening and suboptimal integration at the implant site. The biomaterial surface plays a critical role in promoting osseointegration, which can reduce the risk of device failure. In this study, we propose a novel surface modification on titanium to improve osteogenic differentiation by depositing manganese-containing bioactive glass (BG) on TiO(2) nanotube arrays. The surfaces were characterized by scanning electron microscopy, energy dispersive X-ray spectrometer, contact angle goniometry, and X-ray photoelectron spectroscopy. Cell toxicity, viability, adhesion, and proliferation of adipose-derived stem cells on the surfaces were investigated up to 7 days. To evaluate the osteogenic properties of the surfaces, alkaline phosphatase activity, total protein, osteocalcin expression, and calcium deposition were quantified up to 28 days. The results indicate that TiO(2) nanotube arrays modified with BG promote cell growth and induce increased osteocalcin and calcium contents when compared to unmodified TiO(2) nanotube arrays. The deposition of manganese-containing bioactive glass onto TiO(2) nanotubes demonstrates the ability to enhance osteogenic activity on titanium, showing great potential for use in orthopedic and dental implants.

To address the clinical needs for biodegradable implant materials, in this work, zinc-lithium (Zn-Li) biodegradable alloy was coated with double-doped manganese and strontium resorbable tricalcium phosphate (Mn,Sr-TCP). The Pulsed Laser Deposition method was applied for coating preparation. For coating characterization, Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy coupled with Energy Dispersive X-ray, and X-ray Photoelectron Spectroscopy were used. The microbiology experiments were performed, testing the inhibition of growth of Gram-positive (Staphylococcus aureus, Enterococcus faecalis) and Gram-negative (Salmonella typhimurium, Escherichia coli) bacteria strains and Candida albicans fungus. The obtained results evidenced about 10% of inhibition of all four bacteria strains by the Mn,Sr-TCP-coated Zn-Li samples, exerting the most pronounced effect on C. albicans fungus (about 50% of inhibition of growth). The prepared coatings can be useful for improving the degradation behavior and biological characteristics of Zn-Li alloys.

In the Pollino Massif, in the southern Apennines, the asbestos minerals bearing serpentinites are widely exposed at several quarries (Pietrapica quarry, Timpa Castello quarry, Fagosa quarry and Ghiaia quarry), whose material was extracted and used as aggregates for construction, filling and embankments, and as ornamental stones. Airborne asbestos can be the result of extraction procedure as the stacking, storing and grinding of the serpentinites, so due to the environmental concerns the quarries have been abandoned. In the Pollino Massif serpentinites represent the lherzolitic to harzburgitic upper mantle basament of the Internal Liguride sequence of southern Apennines and can be classified as cataclastic and massive (Dichicco et al., 2015). Cataclastic serpentinites are fractured and deformed whereas those massive show a low fracturing and deformation. The serpentinites have homogeneous mineral compositions and are mainly composed by serpentine polimorphous, asbestiform tremolite, followed by actinolite, chlorite, magnetite and Cr-spinels, and subordinatly calcite, dolomite, and clay minerals. Further, edenite, currently not regulated by the Directive 2003/18/EC of the European Parliament and of the European Council of 27th March 2003, has been recently also detected for the first time (Dichicco et al., 2019). Serpentinite rocks can release significant amounts of fibers of hazardous minerals for the human health, into the air, water and soil, either through geogenic weathering processes or human activity. The observed fibers in the outcrops are of two types: 1) large and elongated fibers that occupy the entire surface of the rock; 2) tiny fibers forming a network throughout the rock.The aim of this work is to characterize in a detailed way the asbestos minerals of representative serpentinite samples taken from the four quarries using the combination of different analytical techniques: field surveys, X-Ray powder diffraction (XRPD), scanning electron microscopy combined with energy dispersive spectrometry (SEM/EDS), µ-Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) in order to assess the impact on the environment and public health.References:Dichicco, M.C.; Laurita, S.; Paternoster, M.; Rizzo, G.; Sinisi, R.; Mongelli, G. Serpentinite Carbonation for CO2. Sequestration in the Southern Apennines: Preliminary Study. Energy Procedia 2015, 76, 477-486.Dichicco, M.C.; Paternoster, M.; Rizzo, G.; Sinisi, R. Mineralogical Asbestos Assessment in the Southern Apennines (Italy): A Review. Fibers 2019, 7, 24.

Asbestiform minerals are potentially toxic and harmful to health and the environment and, in recent years, several studies have been made on the presence of asbestiform minerals in the Pollino Massif, on the border between Lucania and Calabria regions (southern Italy). Moreover, these small fibers can be easily inhaled by humans causing serious health problems especially to the respiratory tract. The formation of asbestiform minerals is related to metamorphism and/or metasomatic alteration of the metamorphic rocks. The main asbestiform mineral phases which have been found in the Pollino Massif are tremolite and, for the first time, edenite and Magnesium-riebeckite. The observed asbestiform minerals found in the metamorphic rocks of the Pollino Massif are thus: i) tremolite, which is characterized by acicular, friable, fibrous, and elongated habitus and was found as intergrowth with fibrous antigorite and chrysotile. In the analyzed rocks, tremolite was found in veins associated with clinopyroxene porphyroclasts; ii) edenite, which is often associated with serpentine, diopside and calcite or occurs as 30 to 80 µm-long single crystals with a fibrous habit. The presence of edenite in the ophiolitic sequences is quite rare and testifies a medium to high metamorphism; iii) magnesium-riebeckite, a record of metamorphic events in blueschist facies, composed of prismatic, acicular crystals with a fibrous habit having length ≥ 5 µm and width < 3 µm with aspect ratio > 3:1. These mineralogical phases were analyzed and characterized using different analytical techniques such as X-ray fluorescence (XRF), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), electron probe micro analysis (EPMA) and X Ray Powder diffraction analysis (XRPD). The aim of this work is to create, for the first time, a geo-mineralogical map of the asbestiform minerals detected in these areas in order to evaluate their spatial distribution.References:Dichicco, M.C.; Laurita, S.; Sinisi, R.; Battiloro, R.; Rizzo, G. Environmental and Health: The Importance of Tremolite Occurence in the Pollino Geopark (Southern Italy). Geosciences 2018, 8, 98.Dichicco, M.C.; Paternoster, M.; Rizzo, G.; Sinisi, R. Mineralogical Asbestos Assessment in the Southern Apennines (Italy): A Review. Fibers 2019, 7, 24.Laurita, S.; Rizzo, G. The First Occurrence of Asbestiform Magnesio-Riebeckite in Schists in the Frido Unit (Pollino Unesco Global Geopark, Southern Italy). Fibers 2019, 7, 79.

With the aim of presenting the processes governing the Laser-Induced Periodic Surface Structures (LIPSS), its main theoretical models have been reported. More emphasis is given to those suitable for clarifying the experimental structures observed on the surface of wide bandgap semiconductors (WBS) and dielectric materials. The role played by radiation surface electromagnetic waves as well as Surface Plasmon Polaritons in determining both Low and High Spatial Frequency LIPSS is briefly discussed, together with some experimental evidence. Non-conventional techniques for LIPSS formation are concisely introduced to point out the high technical possibility of enhancing the homogeneity of surface structures as well as tuning the electronic properties driven by point defects induced in WBS. Among these, double- or multiple-fs-pulse irradiations are shown to be suitable for providing further insight into the LIPSS process together with fine control on the formed surface structures. Modifications occurring by LIPSS on surfaces of WBS and dielectrics display high potentialities for their cross-cutting technological features and wide applications in which the main surface and electronic properties can be engineered. By these assessments, the employment of such nanostructured materials in innovative devices could be envisaged.

Dyes are emerging as hazardous pollutants, which are the primary challenges for environmentalists. Dye removal from effluents is urgently needed. Adsorption technology has been widely employed in this context as an effective method for removing colours from the aqueous phase, and adsorption with the use of low-cost adsorbents has been shown to be more successful on a larger scale than other methods. In this study, spent coffee grounds (SCGs) were used as the precursor for the preparation of a low-cost activated carbon through the chemical activation with NaOH. The SCG sample was impregnated with NaOH and carbonised at 300 °C for three hours. Its morphological and physical-chemical properties were assessed using scanning electron microscopy (SEM), X-ray diffraction, and Raman spectroscopy analyses. The performance of the treated SCG as an adsorbent material for methylene blue (MB) was evaluated by analysing the effect of the initial pH ionic strength on the adsorption capacity and by evaluating the kinetics and the mechanisms of the process (using adsorption isotherms). The effect of the initial concentration (500 and 250 mg L−1) of MB on the kinetics of the process and the impact of the initial pH (7.5 and 6) on the adsorption isotherm were evaluated. The obtained results show that the pseudo-second order model controls the process for both the investigated initial concentration and the adsorption capacity, which are 142.8 and 113.6 mg L−1, respectively. The results indicate that the pH value influences the adsorption isotherm model that regulates the process. Specifically, this process is regulated by the Temkin’s model with a pH of 7.5 and by the Langmuir’s model with a pH of 6. The thermodynamics of the process were also determined. The results show that SCG, treated and carbonised by soft alkaline activation, is a promising low-cost adsorbent material as its performance is comparable to that of conventional active carbon materials.

Pyrolyzed carbons from bio-waste sources are renewable nanomaterials for sustainable negative electrodes in Li- and Na-ion batteries. Here, carbon derived from a hazelnut shell has been obtained by hydrothermal processing of the bio-waste followed by thermal treatments and laser irradiation in liquid. A non-focused nanosecond pulsed laser source has been used to irradiate pyrolyzed carbon particles suspended in acetonitrile to modify the surface and morphology. Morphological, structural, and compositional changes have been investigated by microscopy, spectroscopy, and diffraction to compare the materials properties after thermal treatments as well as before and after the irradiation. Laser irradiation in acetonitrile induces remarkable alteration in the nanomorphology, increase in the surface area and nitrogen enrichment of the carbon surfaces. These materials alterations are beneficial for the electrochemical performance in lithium half cells as proved by galvanostatic cycling at room temperature.

In recent years, significant progress has been made in the development of new technologies to meet the demand for engineered interfaces with appropriate properties for osteochondral unit repair and regeneration. In this context, we combined two methodologies that have emerged as powerful approaches for tissue engineering application: electrospinning to fabricate a nanofibrous polymeric scaffold and pulsed laser deposition to tune and control the composition and morphology of the scaffold surface. A multi-component scaffold composed of synthetic and natural polymers was proposed to combine the biocompatibility and suitable mechanical properties of poly(D,L-lactic acid) with the hydrophilicity and cellular affinity of gelatin. As part of a biomimetic strategy for the generation of bi-functional scaffolds, we coated the electrospun fibers with a thin film of a bioactive glass–ceramic material supplemented with manganese ions. The physico-chemical properties and composition of the bi-layered scaffold were investigated, and its bioactivity, in terms of induced mineralization, was tested by incubation in a simulated body fluid buffer. The processes of the inorganic film dissolution and the calcium phosphate phases growth were followed by microscopic and spectroscopic techniques, confirming that a combination of bioactive glass–ceramics and nanofibrous scaffolds has promising potential in the regeneration of osteochondral tissue due to its ability to induce mineralization in connective tissues.

Microbatteries produced by physical deposition methods are expected to play a pivotal role in many different micro-electronic applications such as stand-alone sensors, implantable or wearable medical devices, radio frequency identification-based systems and smart-cards. In this study pulsed laser deposition (PLD) using a femtosecond-pulsed laser has been applied to TiO2 target materials to produce thin films of anatase-based nanoparticles on aluminum substrates suitable for application as negative electrode in Li-ion MBs. Different post-deposition treatments have been evaluated: films morphology and composition have been investigated with a multi-technique approach and the corresponding performance and electrochemical properties in Li-ion MBs have been analyzed by cyclic voltammetry and galvanostatic techniques. Compact and dense TiO2 films composed by nanoparticles were obtained by PLD with co-crystallization of both anatase and rutile phases. Post-deposition annealing at temperature of 500 °C promote the rutile to anatase phase transition. As deposited TiO2 films are electrochemically almost inactive in lithium half cells, whereas post deposition annealing (either in Ar or Air) boosts the electrochemical activity: air annealing outperforms Ar annealing. The additional deposition of a outer carbon layer by PLD on the TiO2 films further improves the Li+ transport properties, the reversibility of the electrochemical intercalation/de-intercalation reaction as well as the battery performance in terms of capacity retention upon cycling and rate response.

Dense calcium phosphate-based ceramics were fabricated to be used as targets for pulsed laser deposition (PLD). Nanostructured cobalt-substituted hydroxyapatite (Co:HAP) was used as a starting powder. To vary phase composition and microstructure of targets, two sintering approaches were applied, conventional (CS) and two-step sintering (TSS). The obtained results show that in both cases biphasic calcium phosphate (BCP) ceramics (targets) were prepared, with slightly different HAP-to-β–TCP amount ratio and a significantly different microstructure. While the CS method yielded fully dense ceramics with an average grain size of 1.3 μm, the ceramics prepared by TSS had a density of 98.5%, with a predominant grain size below 100 nm. (Ca + Co)P coatings were prepared by PLD of (Ca + Co)P targets. The temperature of the Ti substrate was adjusted to be 25 and 500 °C. The results show that the phase composition of (Ca + Co)P coatings depended on the phase composition of targets as well as on the temperature of the Ti substrate. The coating prepared at 25 °C using CS target consisted of three calcium phosphate phases, HAP, β–TCP and α–TCP; when the TSS target was used, the coating was biphasic, containing HAP and β–TCP. When the substrate was heated to 500 °C, regardless of whether the CS or the TSS target was used, the deposited coatings were composed of HAP and α–TCP. Due to different phase compositions, the (Ca + Co)P coatings deposited at 25 °C showed an improved hardness compared to those deposited at 500 °C. The obtained results confirmed that the phase composition, morphology and mechanical properties of 0.3 μm thick (Ca + Co)P coatings on a Ti substrate can be tailored by employing (Ca + Co)P targets with different microstructures, and also by varying the temperature of the Ti substrate during deposition experiments. Published version: [https://hdl.handle.net/21.15107/rcub_dais_12953] This is the peer reviewed version of the paper: Marković, Smilja, Rau, Julietta V., De Bonis, Angela, De Bellis, Giovanni, Stojanović, Zoran, Veselinović, Ljiljana, Mitrić, Miodrag, Ignjatović, Nenad, Škapin, Srečo Davor, Vengust, Damjan, "Pathway to tailor the phase composition, microstructure and mechanical properties of pulsed laser deposited cobalt-substituted calcium phosphate coatings on titanium" in Surface and Coatings Technology, 437 (2022):128275, [https://doi.org/10.1016/j.surfcoat.2022.128275]

Titanium and its alloys are the most used biomaterials for orthopedic and dental applications. However, up to 10% of these medical devices still fail, mostly due to implant loosening and suboptimal integration at the implant site. The biomaterial surface plays a critical role in promoting osseointegration, which can reduce the risk of device failure. In this study, we propose a novel surface modification on titanium to improve osteogenic differentiation by depositing manganese-containing bioactive glass (BG) on TiO2 nanotube arrays. The surfaces were characterized by scanning electron microscopy, energy dispersive X-ray spectrometer, contact angle goniometry, and X‐ray photoelectron spectroscopy. Cell toxicity, viability, adhesion, and proliferation of adipose-derived stem cells on the surfaces were investigated up to 7 days. To evaluate the osteogenic properties of the surfaces, alkaline phosphatase activity, total protein, osteocalcin expression, and calcium deposition were quantified up to 28 days. The results indicate that TiO2 nanotube arrays modified with BG promote cell growth and induce increased osteocalcin and calcium contents when compared to unmodified TiO2 nanotube arrays. The deposition of manganese-containing bioactive glass onto TiO2 nanotubes demonstrates the ability to enhance osteogenic activity on titanium, showing great potential for use in orthopedic and dental implants.

Asbestos is a term commonly used to refer to those silicate minerals that show a typical fibrous habitus and crystallize as separable fibres. For the past decade, considerable research has focused on the strong correlation between deadly diseases and the exposure to asbestos-like minerals present in different environmental matrices. These harmful minerals generally occur as naturally exposed friable fibres that can be easily released into the environment as a result of both natural processes and anthropogenic activities. At the Calabria-Lucania boundary (southern Italy), the intense spreading of the asbestos fibres is also a consequence of the cataclastic features of the serpentinite outcropping. Therefore, it is necessary to intensify the geo-environmental monitoring in this area. The identification of asbestiform minerals in serpentinites is generally brought about by techniques requiring sample preparation such as: Scanning Electron Microscopy - Energy Dispersion Spectrometry, Transmission Electron Microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, polarized light optical microscopy, and differential thermal analyses. In this work, we evaluate the use of μ-Raman spectroscopy, on both low and high wavenumbers, in identifying the different serpentine and amphibole minerals. The comparison between the μ-Raman spectroscopy and X-ray powder diffraction is also discussed based on analytical procedures and results.

Laser ablation of bulk target in liquid allows to obtain stable nanoparticles and nanostructures, also in metastable phases, limiting the use of hazardous reagents and extreme reaction conditions. Titanium carbide (TiC) is a ceramic compound with several technological applications ranging from biocompatible materials to wear resistant coatings. The possibility to obtain core/shell structures expands its range of application due to the ability of modify the surface properties of the core ceramic material. TiC and metallic titanium targets have been ablated by means of an ultra-short laser source in different liquid media (water, acetone, . n-hexane and toluene). The obtained colloidal solutions have been characterized by TEM, XRD and micro-Raman analysis. In all the used experimental conditions TiC nanoparticles have been produced. During water and acetone mediated ablations, the oxidation of titanium has been observed, whereas by using oxygen free solvents, such as . n-hexane and toluene, core/shell TiC nanoparticles embedded in amorphous and graphitic carbon shell, respectively, have been obtained.

Electrospun scaffolds are emerging as extracellular matrix (ECM)mimicking structures for tissue engineering thanks to their nanofibrous architecture. For the development of suitable electrospun scaffolds for bone tissue engineering, the addition of inorganic components has been implemented with the aim to confer important bioactivity like osteoinduction, osteointegration, and cell adhesion to the scaffolds. In this context, we propose a tricomponent electrospun scaffold composed of poly(d,l-lactide), gelatin and RKKP glass-ceramics. The bioactive RKKP glass-ceramic system has attracted interest, due to the presence of ions such as La3+ and Ta5+ , which turned out to be valuable as growth supporting agents for bones. In this work, RKKP glass-ceramics were embedded inside the microfibers of electrospun scaffolds and the structural and biological properties were investigated. Our results showed that the glass-ceramic microparticles were uniformly distributed in the fibrous structure of the scaffold. Furthermore, the glass-ceramics promoted biomineralization of the scaffolds and improved cell viability and osteogenic differentiation. The mineralized layer formed on RKKP-containing scaffolds after incubation in simulated body fluid medium has been shown to be hydroxyapatite by Raman spectroscopy and X-ray diffraction. The results on differentiation studies of canine adipose-derived mesenchymal stem cells grown on the electrospun scaffolds suggest that on varying the content of RKKP in the scaffold, it is possible to drive the differentiation toward chondrogenic or osteogenic commitment. The presence of ions, like La3+ and Ta5+ , in the RKKP embedded polymeric composite scaffolds could play a role in supporting cell growth and promoting differentiation.

Cancer metastasis is the leading cause of morbidity and cancer-related death. Bone is one of the most favored sites of metastatic spread, particularly from breast cancer. However, our understanding on how the host tissue can impact tumor growth is weak. This is hampered by the lack of a reliable in vitro model ables to replicate the complex microenvironment. Indeed, bone microenvironment provides physical support to cells but it can also affect cell behaviour and phenotype. We developed a hybrid 3D collagen-based scaffold functionalized with hydroxyapatite material (HA) in order to mimic natural bone features. Scaffolds were synthesized in our laboratory through collagen solution mixed and cross-linked with hydroxyapatite. Then, we cultured MDA-MB-231, a triple negative breast cancer cell line and MCF-7, an ER+ breast cancer cell line in collagen or hybrid scaffold, in order to evaluate how extracellular matrix affects cell behavior. Cell growth was evaluated by MTT cell-proliferation assay in a time course analysis. Moreover, we evaluated cell morphology and cell disposition within the scaffold by confocal microscopy. Finally, gene profiling was evaluated by qRT-PCR. MCF-7 cells acquire an organized and linear structure, whereas MDA-MB-231 an epithelial-like morphology, when cultured in hybrid scaffold. MDA-MB-231 cells proliferate faster than MCF-7 in both models. However, this is not affected by hydroxyapatite since the proliferation rate is similar when cells are cultured in collagen or hybrid scaffold. MDA-MB-231 grown in hybrid scaffold show a significant increase in RANKL/OPG ratio, pathway strictly involved in bone homeostasis. Moreover, they show a significant increased expression in JAG1, MMP2 and SNAIL1. For MCF-7, we observe a decrease in CDH1/VIM expression ratio and a significant decrease in OPG, osteoclastogenesis inhibitory factor. Overall, these results suggest a shift induced by hydroxyapatite scaffold towards an osteolytic phenotype. Whereas collagen-scaffold could better simulate in vivo primary tumor (Liverani C. et al, Sci Rep 9, 12263, 2019), we highlight that hybrid hydroxyapatite/collagen scaffold is more suitable to study breast cancer cells behaviour in bone metastasis. Then, we will implement it with a direct co-culture of osteoclast and osteoblast cells, in order to better investigate the contribution of the host microenvironment in bone metastasis. This model could provide a reliable 3D in vitro model for the study of bone metastasis mechanisms and for drug screening assays. Citation Format: Chiara Spadazzi, Laura Mercatali, Alessandro De Vita, Chiara Liverani, Claudia Cocchi, Giacomo Miserocchi, Alberto Bongiovanni, Federica Recine, Sebastiano Calpona, Nada Riva, Giandomenico Di Menna, Lorena Gurrieri, Valentina Fausti, Silvia Angela De Bonis, Giovanni Martinelli, Nicola Baldini, Toni Ibrahim. Development of a biomimetic 3D scaffold to study breast cancer bone metastasis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 333.

Substituting small molecule drugs with abundant and easily affordable ions may have positive effects on the way countless disease treatments are approached. The interest in strontium cation in bone therapies soared in the wake of the success of strontium ranelate in the treatment of osteoporosis. A new method for producing thin strontium-containing hydroxyapatite (Sr-HA, Ca9Sr(PO4)6(OH)2) films as coatings that render bioinert titanium implants bioactive is reported here. The method is based on the combination of a mechanochemical synthesis of Sr-HA targets and their deposition in form of thin films on top of titanium with the use of laser ablation at low pressure. The films were 1 - 2 µm in thickness and their formation was studied at different temperatures, including 25, 300 and 500 oC. Highly crystalline Sr-HA target transformed during pulsed laser deposition to a fully amorphous film, whose degree of long-range order recovered with temperature. Particle edges became somewhat sharper and surface roughness moderately increased with temperature, but the (Ca+Sr)/P atomic ratio, which increased 1.5 times during the film formation, remained approximately constant at different temperatures. Despite the mostly amorphous structure of the coatings, their affinity for capturing atmospheric carbon dioxide and accommodating it as carbonate ions that replace both phosphates and hydroxyls of HA was confirmed in an X-ray photoelectron spectroscopic analysis. As the film deposition temperature increased, the lattice voids got reduced in concentration and the structure gradually "closed", becoming more compact and entailing a linear increase in microhardness with temperature, by 0.03 GPa/oC for the entire 25 - 500 oC range. Biocompatibility and bioactivity of Sr-HA thin films deposited on titanium were confirmed in an interaction with dental pulp stem cells, suggesting that these coatings, regardless of the processing temperature, may be viable candidates for the surface components of metallic bone implants.

The deposition of thin films of bioactive materials is the most common approach to improve the bone bonding ability of an implant surface. With this purpose, several wet and plasma assisted deposition methods were proposed in the scientific literature. In this review, we considered films obtained by nanosecond Pulsed Laser Deposition (PLD). Since hydroxyapatite (HA) has composition and structure similar to that of the mineral component of the bone, the initial studies focused on the selection of experimental conditions that would allow the deposition of films that retain HA stoichiometry and crystallinity. However, biological apatite was found to be a poorly crystalline and multi-substituted mineral; consequently, the attention of researchers was oriented towards the deposition of substituted HA, glass (BG), and glass-ceramic (BGC) bioactive materials to exploit the biological relevance of foreign ions and crystallinity. In this work, after a description of the nanosecond ablation and film growth of ceramic materials, we reported studies on the mechanism of HA ablation and deposition, evidencing the peculiarities of PLD. The literature concerning the PLD of ion substituted HA, BG, and BGC was then reviewed and the performances of the coatings were discussed. We concluded by describing the advantages, limitations, and perspectives of PLD for biomedical applications.

Silicate (13-93) and borate (13-93-B3) bioactive glass coatings were successfully deposited on titanium using the nanosecond Pulsed Laser Deposition technique. The coatings&rsquo, microstructural characteristics, compositions and morphologies were examined by a number of physico-chemical techniques. The deposited coatings retain the same functional groups of the targets, are a few microns thick, amorphous, compact and crack free. Their surface is characterized by the presence of micrometric and nanometric particles. The surface topography, investigated by Atomic Force Microscopy, is characterized by spherical or ellipsoidal particles of the 0.2&ndash, 3 &mu, m size range for the 13-93 silicate bioactive glass film and of the 0.1&ndash, 1 &micro, m range for the 13-93-B3 borate bioactive glass coating. Equine adipose tissue-derived mesenchymal stem cells (ADMSCs) were applied for biological tests and the osteogenic differentiation activity of cells on the deposited coatings was studied after ADMSCs growth in osteogenic medium and staining with Alizarin Red. Cytocompatibility and osteogenic differentiation tests have shown that thin films retain the biocompatibility properties of the target silicate and borate glass, respectively. On the other hand, no antibacterial activity of the borate glass films was observed, suggesting that ion doping is advisable to inhibit bacterial growth on the surface of borate glass thin films.

Oxides, borides and carbides of the transition elements are materials of great interest from a technologic point of view. Many of these materials are used in the form of thin films, so several techniques are commonly used to deposit them. Among these techniques, Pulsed Laser Deposition (PLD) performed using ultra-short pulse lasers, mainly fs lasers, presents unique characteristics in respect to PLD performed using conventional short pulse lasers. Indeed, the films deposited using fs PLD are often nanostructured, and this technique often allows the target stoichiometry to be transferred to the films. In this work, we will review the use of ultra-short PLD in the production of films obtained from transition metal oxides, borides and carbides, evidencing the advantages offered by this technique, together with the problems arising with some of the studied systems. We conclude that even if ultra-short PLD is surely one of the most important and useful deposition techniques, it also presents limits that cannot be ignored.

Bioactive glasses are well-known materials suitable for bone-related applications thanks to their biocompatibility and osteoconductivity. In order to improve their in vivo performance, the modification of the glass composition by adding ions with specific biological functions is required. As copper (Cu) possesses antibacterial properties, in this study, 5 wt % of CuO has been added to the 45S5 bioactive glass composition. The investigation of the effect of the Cu-containing bioactive glass on cellular behavior has revealed that the presence of Cu induces an early differentiation of human mesenchymal stem cells through osteoblast phenotype, Target la earn promotes the expression of anti-inflammatory interleukin, and reduces proinflammatory interleukin expression. With the aim to produce coatings with antibacterial properties, the Cu-containing bioactive glass was used as the target material for the pulsed laser deposition (PLD) of bioactive thin films. PLD experiments were carried out at different substrate temperatures to study the effect on the film's characteristics. All of the films are compact, crack-free, and characterized by a rough morphology and good wettability. The in vitro bioactivity was demonstrated by the apatite growth on the coating surface, after soaking in simulated body fluid, revealed by Raman spectroscopy and scanning electron microscopy-energy dispersive X-ray analyses. The antibacterial study proved that the material showed more effective activity against three Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica) rather than against Gram-positive bacteria (Staphylococcus aureus).

In this work we discuss the co-catalysis in aprotic Li-O 2 batteries of C-free nanostructured mixed oxide electrodes decorated by Pd/PdO core/shell nanoparticles. A Cr(III) doped NiCo 2 O 4 material has been grown hydrothermally on an open Ni-mesh. Palladium nanoparticles have been synthesized by pulsed lased ablation in liquid acetone in the fs regime and deposited by drop casting onto the surface of the nanostructured mixed oxide electrodes. The resulting electrodes have been calcined at 300 ◦ C. The use of laser techniques to produce nanoparticles for aLOBs is here proposed for the first time in the literature, as well as the peculiar combination of Pd/PdO nanoparticles deposited onto C-free Cr(III) doped NiCo 2 O 4 self-standing electrodes. Performance in aprotic Li-O 2 batteries have been recorded in galvanostatic conditions and post mortem analysis of the electrode surfaces have been carried out by X-ray photoemission spectroscopy. The use of Pd/PdO nanoparticles as co-catalysts enhances the reversibility of the electrochemical oxygen reduction/evolution reactions. This beneficial effect originates by the decrease of the mean overvoltages compared to the bare Cr(III) doped NiCo 2 O 4 electrodes, and extends the cell calendar life from 16 to 41 fully reversible galvanostatic cycles at J = 0.2 mAcm− 2 with capacity limitation of 0.2 mAhcm− 2 .

Titanium (Ti) and its alloys are extensively used nowadays for dental and orthopaedic implants due to their outstanding mechanical characteristics and acceptable biocompatibility. However, the properties of metal implant/native hard tissue interface can be substantially improved, if titanium is coated by bioactive materials, with the scope to optimise the long-term characteristics of implant, to elicit a required cellular response, and, as a final goal, to provide better performance and increased functionality of the implant. As future implants, Magnesium (Mg) biodegradable alloys are very promising biocompatible materials for biodegradable biomedical implants, such as, for example, orthopaedic fracture fixation pins or screws. They decompose in the conditions of human body, releasing the Mg2+ ion, which has a functional role in many physiological processes. Moreover, Mg alloys have outstanding mechanical properties, similar to that of the natural bone tissue. However, the main problem in using Mg alloys for biomedical implants is their fast degradation in human body conditions, if compared to the native bone tissue growth. This drawback of Mg alloys can be improved by applying protective coatings of ceramic and composite materials, as prospective solution to control the in vitro degradation. Doped (substituted) calcium phosphates and glass-ceramics are perspective materials for coatings on Ti and Mg alloys [1-9]. They provide superficial affinity, functional interface and improved osseointegration. Substituted calcium phosphates can endow coatings with a broad range of particular functional properties, from antibacterial to the magnetic one [1,2,4,5,8,9]. Whereas the focus point of bioactive glass-ceramic materials is their ability to continuously exchange ions with physiological liquids and to release appropriate active trace elements to stimulate cellular response aimed to activate genes responsible for osteogenesis and tissue regeneration [3,6]. In this work, we report the results on deposition of substituted hydroxyapatite (HA) implant coatings, such as Carbonate-HA [1], Fluorine (F)-HA [2], Silicate-HA [4], Iron (Fe)-HA [5], and Zink (Zn)-HA [8]. Furthermore, the results regarding several glass-ceramic composition coatings will be reported [3,6]. The bulk glass-ceramics materials for coating deposition were prepared by sol-gel method. All the coatings were deposited using Pulsed Laser Deposition technique (PLD). It presents several advantages, compared to other deposition techniques, such as the congruent transfer of the target composition to the coating, the possibility to vary film's thickness, degree of crystallinity, adherence, surface morphology and topography, varying the experimental parameters, such as deposition temperature, time, laser pulse length and wavelength. It has been widely used to deposit thin films of ceramic and glass biomaterials onto biocompatible and biodegradable substrates. Films deposited by nanosecond laser sources present micro- and nanostructured morphology favouring the interaction of surface with cells. The properties of coatings were investigated by a number of physico-chemical techniques, such as X-Ray diffraction, FTIR spectroscopy, Raman spectroscopy, atomic force microscopy, scanning electron microscopy (SEM-EDS), and Vickers hardness. In vitro bioactivity and cell tests for the deposited coatings were performed.

A MgB2target has been ablated by Nd:glass laser with a pulse duration of 250 fs. The plasma produced by the laser-target interaction, showing two temporal separated emissions, has been characterized by time and space resolved optical emission spectroscopy and ICCD fast imaging. The films, deposited on silicon substrates and formed by the coalescence of particles with nanometric size, have been analyzed by scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. The first steps of the films growth have been studied by Transmission Electron Microscopy. The films deposition has been studied by varying the substrate temperature from 25 to 500°C and the best results have been obtained at room temperature.

Chromium borides are promising candidates for several structural applications including protective coatings for materials exposed to corrosive and abrasive environments. In this paper the pulsed laser deposition of chromium diboride-rich thin films has been carried out in vacuum by using a frequency doubled Nd:glass laser with a pulse duration of 250 fs. The films have been deposited at different substrate temperatures and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. Lastly, the film&rsquo, s hardness has been studied by Vickers indentation technique. The results indicate that only the films deposited at a substrate temperature of 500 &deg, C are crystalline and formed by chromium diboride, together with a certain amount of boron and chromium, which suggests that, as main mechanism, a process taking place on the surface from atoms and ions from the gas phase. This hypothesis has been confirmed by the study of the plasma produced by the ablation process.

e13549 Background: Hematologic markers of inflammation have been shown to be prognostic in different malignancies. Also in glioblastoma multiforme (GBM) a prognostic role has been demonstrated. The purpose of this study is to evaluate retrospectively the prognostic role of these markers in patients receiving a concomitant radio-chemotherapy after surgery. Methods: Sixty-five GBM patients have been treated with concomitant radio-chemotherapy after surgery at our institute from 2008 to 2017. Information on blood counts were carried out the day before starting therapy and after the day before the last cycle of chemotherapy. Neutrophil/lymphocyte ratio (NLR) and Platelet/lymphocyte ratio (PLR) were computed as the ratio of the absolute neutrophil count and absolute platelet count by the absolute lymphocyte count respectively. Systemic Inflammatory Index (SII) was calculated as platelet count × neutrophil count/lymphocyte count. The optimal cut-point was obtained using X-tile software version 3.6.1. Results: NLR and PLR baseline value didn’t show a statistic a statistically significant prognostic role in PFS or OS. Patients with baseline SII < 480 showed both better PFS and OS (OS: 22.1 VS 11.8 mo p-values 0.0516; PFS: 10.6 VS 5.7 mo p-values 0.0351). Patients aged < 60 years showed better PFS and OS. (PFS 10.3 VS 5.5 p-values 0.0501; OS: 20.6 VS 11.2 mo p-values 0.0124). Statistical significance for SII and age was maintained for both PFS and OS in multivariate analysis as shown in Table 1. Baseline values of NLR PLR and SII have also been correlated with the best response and ORR without showing statistical significance. Conclusions: This restorative study confirms the prognostic value of inflammatory indices in patients with GBM. Correlation analysis with the methylation status of MGMT is ongoing.[Table: see text][Table: see text]

Palladium nanoparticles are a valuable alternative to molecular catalysts for not requiring costly and toxic ligands. In this study palladium nanoparticles were produced by either pulsed laser ablation in liquid or direct reactions between ascorbic acid and a palladium salt. The obtained nanoparticles have been characterized by TEM, XRD and XPS techniques and they have been applied to the catalysis of the ligand-free Suzuki-type cross-coupling reaction. Methyl ( E )-4-bromocrotonate has been coupled to different aryl and heteroarylboronic acids with yield up to 81% and selectivity between 85 and 90%. Investigations on catalytic reusability of the NPs have shown that they could be used for three or ten catalytic cycles without loss of activity, respectively for LAL or chemically synthesized Pd NPs.

Biocompatibility of bio-inert materials can be improved by coating substrates with bioactive films. We have used Pulsed Laser Deposition (PLD) technique to deposit thin films of a biphasic target MICA/apatite on Silicon and Titanium substrates. Morphology, surface roughness and composition of films have been characterized, showing that PLD is a flexible technique to deposit films suitable for biomedical applications.

The formation of an opaque solid foam was induced by the direct interaction between tetraethyl orthosilicate (TEOS) and an ultrashort femtosecond laser source(Nd:glass, 527 nm, 10 Hz, 250 fs). The product, which resulted to be a silica xerogel, was characterized by different techniques. In particular, information about the morphology was obtained by scanning and transmission electron microscopy (SEM and TEM), while the presence of different functional groups was studied through IR measurements. Since the properties of this kind of material can be improved by functionalizing it with metal nanoparticles, a palladium metal target was ablated in liquid TEOS. TEM images show that palladium was present in the form of nanoparticles and EDX measurements confirm the presence of the metal inside the silica network.

The ultrashort pulsed laser deposition of vanadium oxide thin films has been carried out by a frequency-doubled Nd:glass laser with a pulse duration of 250 fs. The characteristics of the plasma produced by the laser-target interaction have been studied by ICCD imaging and optical emission spectroscopy. The results confirm that an emitting plasma produced by ultrashort laser pulses is formed by both a primary and a secondary component. The secondary component consists of particles with a nanometric size, and their composition and spatial angular distribution influence the deposited films. In fact, these films, analyzed by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, and atomic force microscopy, are formed by the aggregation of a large number of nanoparticles whose composition is explained by a model based on equilibrium thermal evaporation from particles directly ejected from the target. On these basis, the presence in the films of a mixture of V(2)O(5) and VO(2) is discussed.

The synthesis of gallium arsenide (GaAs) nanoparticles has attracted wide scientific and technological interest due to the possibility of tuning the GaAs NP (nanoparticle) band gap across the visible spectrum and their consequent use in optoelectronic devices. In recent years, laser ablation in liquid (LAL) has been widely used for the preparation of colloidal solutions of semiconducting and metallic nanoparticles, thanks to its flexibility. With the aim of highlighting the key role played by laser pulse duration on the ablation mechanism and on the properties of the obtained materials, laser ablation of a gallium arsenide target in acetone was performed using laser sources operating in two different temporal regimes: Nd: glass laser (lambda = 527 nm, pulse duration of 250 fs and frequency repetition rate of 10 Hz) and Nd: YAG laser (lambda = 532 nm, pulse duration of 7 ns and frequency repetition rate of 10 Hz). The ablation process was studied following the dynamics of the laser induced shock waves (SWs) and cavitation bubbles (CBs) by fast shadowgraphy, showing that CB dimension and lifetime is related to the laser pulse length. A characterization of the obtained materials by TEM (transmission electron microscopy) and microRaman spectroscopy have shown that quite spherical gallium oxide/GaAs nanoparticles can be obtained by nanosecond laser ablation. On the other hand, pure polycrystalline GaAs nanoparticles can be produced by using an ultrashort laser source.

In this work the analysis by Laser Induced Breakdown Spectroscopy (LIBS) technique of copper-based alloys having different composition and performed with fs laser pulses is presented. A Nd:Glass laser (Twinkle Light Conversion, λ = 527 nm at 250 fs) and a set of bronze and brass certified standards were used. The inverse Calibration-Free method (inverse CF-LIBS) was applied for estimating the temperature of the fs laser induced plasma in order to achieve quantitative elemental analysis of such materials. This approach strengthens the hypothesis that, through the assessment of the plasma temperature occurring in fs-LIBS, straightforward and reliable analytical data can be provided. With this aim the capability of the here adopted inverse CF-LIBS method, which is based on the fulfilment of the Local Thermodynamic Equilibrium (LTE) condition, for an indirect determination of the species excitation temperature, is shown. It is reported that the estimated temperatures occurring during the process provide a good figure of merit between the certified and the experimentally determined composition of the bronze and brass materials, here employed, although further correction procedure, like the use of calibration curves, can be demanded. The reported results demonstrate that the inverse CF-LIBS method can be applied when fs laser pulses are used even though the plasma properties could be affected by the matrix effects restricting its full employment to unknown samples provided that a certified standard having similar composition is available.

In this work, titanium (Ti) supports have been coated with glass-ceramic films for possible applications as biomedical implant materials in regenerative medicine. For the film preparation, a pulsed laser deposition (PLD) technique has been applied. The RKKP glass-ceramic material, used for coating deposition, was a sol-gel derived target of the following composition: Ca-19.4, P-4.6, Si-17.2, O-43.5, Na-1.7, Mg-1.3, F-7.2, K-0.2, La-0.8, Ta-4.1 (all in wt%). The prepared coatings were compact and uniform, characterised by a nanometric average surface roughness. The biocompatibility and cell-friendly properties of the RKKP glass-ceramic material have been tested. Cell metabolic activity and proliferation of human colon carcinoma CaCo-2 cells seeded on RKKP films showed the same exponential trend found in the control plastic substrates. By the phalloidin fluorescence analysis, no significant modifications in the actin distribution were revealed in cells grown on RKKP films. Moreover, in these cells a high mRNA expression of markers involved in protein synthesis, proliferation and differentiation, such as villin (VIL1), alkaline phosphatase (ALP1), beta-actin (beta-ACT), Ki67 and RPL34, was recorded. In conclusion, the findings, for the first time, demonstrated that the RKKP glass-ceramic material allows the adhesion, growth and differentiation of the CaCo-2 cell line.

LiCoPO4 (LCP) is a promising candidate as alternative cathode for high-voltage lithium-ion batteries. However, its practical electrochemical performances are still far from the theoretical data likely due to the low electronic and ionic conductivities. Moreover LCP typically suffers a rapid capacity fading upon cycling, probably due to structural degradations and electrolyte decomposition at 5 V vs. Li+/Li. Previous studies showed that carbon coating and metal doping may improve LCP electrochemical properties. In this work we report: (a) the fine tuning of a novel synthetic route at low temperature to obtain micrometric LCP crystallites morphologically homogeneous and crystallographically pure; (b) the analysis of the effect of iron doping on LCP structural features and electrochemical properties in lithium cell; (c) the beneficial simultaneous effect of iron doping and post-synthesis high-temperature annealing on the electrochemical performances in Li cells. The optimized material shows a reversible capacity of 120 mAh g−1 at 0.1C rate and a capacity retention of 78% after 20 cycles.

The adsorption process of 2,2′: 2′,5″-terthiophene molecules on two different types of silver surfaces was studied by means of surface enhanced Raman scattering (SERS) and UV–Vis absorption spectroscopy. Both techniques support the hypothesis of an adsorption-induced polymerisation process of these molecules. The vibrational pattern of the chemisorbed layer was found to be almost identical with that of bulk polythiophene samples and a red shift from 3.5 to 2.5 eV of the electronic absorption is observed in agreement with the Kuhn–Kuhn model. A concomitant decrease in visible photoluminescence was also observed.

The films obtained by ultra-short pulsed laser deposition of a target of molybdenum carbide, at different substrate temperatures, have been characterized by different techniques, including scanning electron microscopy, micro-Raman spectroscopy and X-ray photoelectron spectroscopy. The results indicate that the films are formed by a large number of particles with nanomentric dimensions and are composed mainly of Mo2C. The presence of an excess of carbon, found in the films, is probably due the presence of a certain amount of graphite in the target (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Attempts to synthesize and/or theoretically predict new superhard materials are the subject of an intense research activity. The trials to deposit them in the form of films have just began. WB(2) (77 wt % WB(2) and 23 wt % WB(4)) and WB(4) (65 wt % WB(4) and 35 wt % WB(2)) polycrystalline bulk samples were obtained in this work via electron beam synthesis technique and, subsequently, used as targets for films preparation by the pulsed laser deposition method. The targets were irradiated by a frequency-doubled Nd:glass laser with a pulse duration of 250 fs. The films grown on SiO(2) substrates at 600 °C were characterized by X-ray diffraction, scanning electron and atomic force microscopies, and Vickers microhardness technique. The deposited films are composed of WB(4). The intrinsic film hardness, calculated according to the "law-of-mixtures" model, lies in the superhardness region 42-50 GPa.

Self-assembled monolayers (SAMs) of different length have been built onto silver surfaces suitable for surface enhanced Raman (SER) effect. The analysis of the surface enhanced Raman spectra as a function of the monolayer thickness allowed to study SER effect by changing the distance in a nanometric way. In this work, we present a case of distance dependence in which SER spectra of terthiophene are studied for molecules deposited onto SAMs previously adsorbed on roughened silver. Each spacer is able to inhibit the oligomerization of terthiophene already observed by us, when the molecules are adsorbed onto bare silver. It will also be shown how the spectral features of the deposited terthiophene gradually vary by changing the spacer thickness from 0.8 to 2.5 nm.