Probing the effectiveness of barrier creams against human skin penetration of nickel powder.

OBJECTIVE: Barrier creams (BCs) are marketed as locally applied medical devices or cosmetic products to protect the skin from exposure to chemicals and irritants. Generally, the mechanism of action of such products is mainly due to the formation of a superficial thin film between the skin and the irritant or sensitizer, thus reducing or totally blocking the cutaneous penetration of such agents. Specifically, studies focusing on the effectiveness of commercial protective creams to prevent nickel cutaneous penetration are extremely scarce. The aim of the current work, therefore, is to evaluate the protective role of a commercially available barrier cream for nickel and compare the results with a simple moisturizing, following exposure to Ni powder. METHODS: Marketed BCs were evaluated and tested. Human skin absorption of Ni was studied in vitro using static Franz diffusion cells. RESULTS: Our results demonstrate that the application of both formulations caused a reduction of Ni inside the skin (8.00 ± 3.35 µg cm-2 for the barrier cream and 22.6 ± 12.6 µg cm-2 for the general moisturizing product), with the specialized barrier cream being statistically (p = 0.015) more efficient on forming a protective barrier, thus evidencing the importance of some ingredients in such formulations on the nickel dermal accumulation. CONCLUSIONS: The composition of the formulations based on film-forming or chelating agents may play an imperative role in reducing the cutaneous penetration of Ni.

OBJECTIF: Les crèmes de barrière (CB) sont commercialisées en tant que dispositifs médicaux ou produits cosmétiques appliqués localement pour protéger la peau contre l'exposition aux produits chimiques et irritants. En général, le mécanisme d'action de ces produits est principalement dû à la formation d'un film mince superficiel entre la peau et l'irritant ou le sensibilisant, réduisant ainsi ou bloquant totalement la pénétration cutanée de ces agents. Plus précisément, les études portant sur l'efficacité des crèmes protectrices commercialisées pour prévenir la pénétration cutanée du nickel sont extrêmement rares. L'objectif du projet en cours est donc d'évaluer le rôle protecteur d'une crème barrière disponible dans le commerce contre le nickel et de comparer les résultats à un simple hydratant après une exposition à la poudre de Ni. MÉTHODES: Des CB commercialisées ont été évaluées et testées. L'absorption cutanée du Ni dans la peau humaine a été étudiée in vitro à l'aide de cellules de diffusion statiques de Franz. RÉSULTATS: Nos résultats démontrent que l'application des deux formulations a entraîné une réduction du taux de Ni à l'intérieur de la peau (8,00 ± 3,35 µg·cm-2 pour la crème barrière et 22,6 ± 12,6 µg·cm-2 pour le produit hydratant ordinaire), la crème barrière spécialisée étant statistiquement (p = 0,015) plus efficace pour former une barrière protectrice, démontrant ainsi l'importance de certains ingrédients dans ces formulations sur l'accumulation dermique du nickel. CONCLUSIONS: La composition des formulations basées sur des agents de formation de film ou de chélation peut jouer un rôle nécessaire pour réduire la pénétration cutanée du Ni.

Reduced Tiara-like Palladium Complex for Suzuki Cross-Coupling Reactions.

The design of highly active and structurally well-defined catalysts has become a crucial issue for heterogeneous catalysed reactions while reducing the amount of catalyst employed. Beside conventional synthetic routes, the employment of polynuclear transition metal complexes as catalysts or catalyst precursors has progressively intercepted a growing interest. These well-defined species promise to deliver catalytic systems where a strict control on the nuclearity allows to improve the catalytic performance while reducing the active phase loading. This study describes the development of a highly active and reusable palladium-based catalyst on alumina (Pd8 /Al2 O3 ) for Suzuki cross-coupling reactions. An octanuclear tiara-like palladium complex was selected as active phase precursor to give isolated Pd-clusters of ca. 1 nm in size on Al2 O3 . The catalyst was thoroughly characterised by several complementary techniques to assess its structural and chemical nature. The high specific activity of the catalyst has allowed to carry out the cross-coupling reaction in 30 min using only 0.12 mol % of Pd loading under very mild and green reaction conditions. Screening of various substrates and selectivity tests, combined with recycling and benchmarking experiments, have been used to highlight the great potentialities of this new Pd8 /Al2 O3 catalyst.

From Collection or Archaeological Finds? A Non-Destructive Analytical Approach to Distinguish between Two Sets of Bronze Coins of the Roman Empire.

This study stems from the need for numismatics to establish whether there may be relationships between a group of 103 bronze coins from the Roman era found in archaeological excavations on the Cesén Mountain (Treviso, Italy) and a group of 117 coins kept at the Museum of Natural History and Archaeology in Montebelluna (Treviso, Italy). The chemists were delivered six coins with neither pre-agreements nor further information on the origin of the coins. Therefore, the request was to hypothetically assign the coins to the two groups on the basis of similarities and differences in their surface composition. Only non-destructive analytical techniques were allowed to be used to characterize the surface of the six coins taken blindly from the two sets. The elemental analysis of each coins' surface was carried out by µ-XRF. To better observe the morphology of the coins' surfaces, SEM-EDS was used. Compounds covering the coins coming from both corrosion processes (patinas) and the deposition of soil encrustations were also analyzed by means of the FTIR-ATR technique. The molecular analysis confirmed the presence of silico-aluminate minerals on some coins, unequivocally indicating a provenance from clayey soil. Some soil samples, collected from the archaeological site of interest, were analyzed to verify whether the encrusted layer on coins could contain chemical components compatible with them. This result, together with the chemical and morphological investigations, led us to subdivide the six target coins into two groups. The first group is made up of two coins coming from the set of coins from excavation (found in the subsoil) and from the set from open air finds (coins found in the top layer of the soil). The second group is made up of four coins that are devoid of characteristics corresponding to exposure to soil contact for long periods of time and, moreover, their surface compounds could suggest a different provenance. The analytical results of this study made it possible to correctly assign all six coins to the two groups of finds and support numismatics, which was unconvinced in considering all coins to come from the same finding site only on the basis of archaeological documentations.

A Multi-Analytical Approach on Silver-Copper Coins of the Roman Empire to Elucidate the Economy of the 3rd Century A.D.

In this study, 160 silver-copper alloy denarii and antoniniani from the 3rd century A.D. were studied to obtain their overall chemical composition. The approach used for their characterisation is based on a combination of physical, chemical, and chemometric techniques. The aim is to identify and quantify major and trace elements in Roman silver-copper coins in order to assess changes in composition and to confirm the devaluation of the currency. After a first cataloguing step, µ-EDXRF and SEM-EDX techniques were performed to identify the elements on the coins' surface. A micro-destructive sampling method was employed on a representative sample of the coins to quantify the elements present in the bulk. The powder obtained from drilling 12 coins (keeping the two categories of coins separate) was dissolved in an acidic medium; heated and sonicated to facilitate dissolution; and then analysed by ICP-AES and ICP-MS. The two currencies had different average alloy percentages; in particular, the % difference of Ag was about 8%. The other elements were found in concentrations <1 wt%. Of these, the element highest in concentration were Pb and Sn, which is in agreement with the literature. The multivariate analysis performed on the data acquired revealed two groups of coins, corresponding to the two currencies.

Cerium Oxide Nanoparticles Absorption through Intact and Damaged Human Skin.

Cerium oxide (CeO2) nanoparticles (NPs) are used in polishing products and absorbents, as promoters in wound healing, and as organopesticide decontaminants. While systemic bioaccumulation and organ toxicity has been described after inhalation, data on CeO2 NPs' transdermal permeation are lacking. Our study was an in vitro investigation of the permeation of 17-nm CeO2 NPs dispersed in synthetic sweat (1 g L-1) using excised human skin on Franz cells. Experiments were performed using intact and needle-abraded skin, separately. The average amount of Ce into intact and damaged skin samples was 3.64 ± 0.15 and 7.07 ± 0.78 µg cm-2, respectively (mean ± SD, p = 0.04). Ce concentration in the receiving solution was 2.0 ± 0.4 and 3.3 ± 0.7 ng cm-2 after 24 h (p = 0.008). The Ce content was higher in dermal layers of damaged skin compared to intact skin (2.93 ± 0.71 µg cm-2 and 0.39 ± 0.16 µg cm-2, respectively; p = 0.004). Our data showed a very low dermal absorption and transdermal permeation of cerium, providing a first indication of Ce skin uptake due to contact with CeO2.

Melanization Affects the Content of Selected Elements in Parmelioid Lichens.

Lichens belonging to Parmeliaceae are highly diversified, but most of them share an extremely conserved morpho-chemical trait: the lower cortex is heavily melanized. The adaptive value of this character is still uncertain. Melanins are ubiquitous compounds found in most organisms since they fulfil several biological functions including defense against UV radiation, oxidizing agents, microbial stress, and metal complexation. This work aims to establish whether melanization can affect the elemental content of lichen thalli. The relative abundance of macro- (Ca, K and S) and micro- (Fe, Mn and Zn) nutrients in melanized and non-melanized pseudotissues of nine species was first evaluated by a non-destructive micro-X-ray fluorescence elemental analysis on either the upper and lower cortex, and on the internal medulla, which was artificially exposed to the mechanical removal of the lower cortex. Afterwards, the total concentration of the same elements was measured in composite samples by inductively coupled plasma atomic emission spectroscopy after acidic digestion. In order to verify whether Fe and Zn are chemically bound to the melanized pseudotissues, a sequential elution experiment was performed on two species: the two-side heavily melanized Melanelixia glabratula and the one-side lightly melanized Punctelia subrudecta. The content of Fe and Zn was higher in the melanized species than in the non-melanized ones. Species deprived of their melanized lower cortex showed a sharp decrease in Fe but not in Zn, suggesting that the melanized lower cortex is involved in Fe complexation, whereas Zn is homogeneously distributed throughout the thallus.

Bioaccumulation of thallium and other trace metals in Biscutella laevigata nearby a decommissioned zinc-lead mine (Northeastern Italian Alps).

The mineral body exploited in Salafossa (Eastern Dolomites) was one of the largest lead/zinc-containing mineral deposits in Europe. Both metals were mainly present as sulphides (sphalerite, ZnS and galena, PbS). Mining activity started around 1550, but it was only around 1960 that the richest veins of the minerals were discovered. The mine closed in 1985, and concentrations of several trace metals, such as thallium (Tl), iron (Fe), manganese (Mn), lead (Pb) and zinc (Zn), were detected in the soils and plant samples (Biscutella laevigata L.) that were collected from eighteen sites selected outside the mine. B. laevigata is a pseudometallophyta species, and it often grows near mining areas where the soil's metal concentrations are significantly higher than those of soil with a natural geochemical background. The total metal concentrations in the plant tissue (roots and leaves of Biscutella laevigata) and in the soil samples - both bulk-soil and the B. laevigata root system (rhizo-soil) - were determined through Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The metal extractability and leachability of the soil samples were estimated using soil extractions with DTPA (Diethylenetriaminepentaacetic acid). In addition, metal mobility caused by rainwater runoff was estimated by using a leaching test with a dilute solution of H2SO4 and HNO3. The results showed that metals were present in a chemical form available for uptake by the plants' roots. In fact, high concentrations of the metals were also found in the plant tissue (roots and leaves) of B. laevigata, and these concentrations were higher than those whose soils present natural geochemical background levels in the corresponding rhizo-soil. Thus, B. laevigata has shown a marked ability to bioaccumulate trace metals, especially Tl and, to a lesser extent, Zn, Pb, Fe and Mn, and it can influence metal mobility in the rhizo-soil. To assess the uptake and translocation processes of the trace metals, resulting in their bioaccumulation, two different indices were calculated: the enrichment factor in roots (EFr), as the ratio between the metal concentration in belowground biomass and in the respective rhizo-soil, and the translocation factor (TF), as the ratio between the metal concentration in the leaves and the corresponding roots. For both indices, values > 1 denoted enrichment of the metal in the roots or its translocation to the upper tissues. The results showed that EFr and TF were considerably high only for Tl, reaching a maximum value of 60 for EFr and 11.6 for TF. Conversely, the other investigated metals did not show significant bioaccumulation (EFr < 1), and they showed TF > 1 only at a few sites.

Transdermal nicotine absorption handling e-cigarette refill liquids.

The concentrated nicotine in e-cigarette refill liquids can be toxic if inadvertently ingested or absorbed through the skin. Reports of poisonings due to accidental ingestion of nicotine on refill liquids are rapidly increasing, while the evaluation of nicotine dermally absorbed still lacks. For that reason we studied transdermal nicotine absorption after the skin contamination with e-liquid. Donor chambers of eight Franz diffusion cells were filled with 1 mL of 0.8 mg/mL nicotine e-liquid for 24 h. The concentration of nicotine in the receiving phase was determined by high-performance liquid chromatography (LOD:0.1 µg/mL). Nicotine was detectable in receiving solution 2 h after the start of exposure and increased progressively. The medium flux calculated was 4.82 ± 1.05 µg/cm(2)/h with a lag time of 3.9 ± 0.1 h. After 24 h, the nicotine concentration in the receiving compartment was 101.02 ± 22.35 µg/cm(2) corresponding to 3.04 mg of absorbed nicotine after contamination of a skin surface of 100 cm(2). Skin contamination with e-liquid can cause nicotine skin absorption: caution must be paid when handling refill e-liquids.

Nanoparticles skin absorption: New aspects for a safety profile evaluation.

Nanoparticles (NPs) skin absorption is a wide issue, which needs to be better understood. The attempt of this review is to summarize the scientific evidence concerning open questions, i.e.: the role of NPs intrinsic characteristics (size, shape, charge, surface properties), the penetration of NPs through the intact or impaired skin barrier, the penetration pathways which should be considered and the role of NPs interaction in physiological media. The outcomes suggest that one main difference should be made between metal and non-metal NPs. Both kinds have a secondary NPs size which is given after interaction in physiological media, and allows a size-dependent skin penetration: NPs⩽4nm can penetrate and permeate intact skin, NPs size between 4 and 20nm can potentially permeate intact and damaged skin, NPs size between 21 and 45nm can penetrate and permeate only damaged skin, NPs size>45nm cannot penetrate nor permeate the skin. Other aspects play an important role, mostly for metal NPs, i.e., dissolution in physiological media, which can cause local and systemic effects, the sensitizing or toxic potential and the tendency to create aggregates. This paper suggests a decision tree to evaluate the potential risk for consumers and workers exposed to NPs.

Evaluating the role of protective creams on the cutaneous penetration of Ni nanoparticles.

There is an increase of application of Nickel in the form of nanoparticles (NiNPs) in several fields including modern metallurgy, bioengineering, and medicine. Such growth of the areas of application is actually accompanied with an increase of exposure to Nickel, thus an intensification of the negative effects, the most frequent being the allergic contact dermatitis. Indeed, due to their smaller size, and therefore their higher surface area, NiNPs can release more Ni ions compared to bulk material, that can penetrate and permeate through the skin. To reduce the Ni cutaneous penetration, barrier creams (BC) are applied on the skin surface. There is little information, however, on the efficiency of such commercial protective creams on decreasing Ni cutaneous penetration. For this reason, the objective of the current study was to investigate the protective role of one commercially available formulation for Ni (Nik-L-Block™ containing a chelating agent) and one moisturizing cream (Ceramol 311 basic cream without chelating agent), following exposure to NiNPs, using in vitro Franz cells, as well as the cytotoxicity of NiNPs in primary human dermal fibroblasts was studied. Our results demonstrated that although both tested formulations can decrease Ni accumulation in the skin (4.13 ± 1.74 µg/cm2 for Nik-L-Block™ and 7.14 ± 1.46 µg/cm2 for Ceramol 311 basic cream); there are significant differences between the two creams (p = 0.004). Based on the experimental evidence, we therefore conclude that the composition of such formulations has an imperative role for dermal uptake of Ni. Finally, NiNPs showed no cytotoxic effect on cultured human dermal fibroblasts after 24 and 72 h.

Transdermal permeation of inorganic cerium salts in intact human skin.

The stratum corneum protects the body against external agents, such as metals, chemicals, and toxics. Although it is considered poorly permeable to them, comprising the major barrier to the permeation of such substances, it may become a relevant gate of entry for such molecules. Cerium (Ce) is a lanthanide that is widely used in catalytic, energy, biological and medicinal applications, owing to its intrinsic structural and unique redox properties. Cerium salts used to produce cerium oxide (CeO2) nanostructures can potentially come into contact with the skin and be absorbed following dermal exposure. The objective of this study was to investigate the percutaneous absorption of three inorganic Ce salts: cerium (III) chloride (CeCl3); cerium (III) nitrate (Ce(NO3)3) and ammonium cerium (IV) nitrate (Ce(NH4)2(NO3)6), which are commonly adopted for the synthesis of CeO2 using in vitro - ex vivo technique in Franz diffusion cells. The present work shows that Ce salts cannot permeate intact human skin, but they can penetrate significantly in the epidermis (up to 0.29 µg/cm2) and, to a lesser extent in dermis (up to 0.11 µg/cm2). Further studies are required to evaluate the potential effects of long-term exposure to Ce.

Assessment of dermal absorption of beryllium and copper contained in temple tips of eyeglasses.

Dermal exposure to hazardous substances such as chemicals, toxics, metallic items and other contaminants may present substantial danger for health. Beryllium (Be) is a hazardous metal, especially when inhaled and/or in direct contact with the skin, associated with chronic beryllium disease (CBD) and Be sensitization (BeS). The objective of this study was to investigate the percutaneous penetration of beryllium and copper contained in metallic items as eyeglass temple tips (specifically BrushCAST® Copper Beryllium Casting Alloys containing Be 0.35 < 2.85%; Cu 95.3-98.7%), using Franz diffusion cells. This work demonstrated that the total skin absorption of Cu was higher (8.86%) compared to Be (4.89%), which was expected based on the high percentage of Cu contained in the eyeglass temple tips. However, Be accumulated significantly in the epidermis and dermis (up to 0.461 µg/cm2) and, to a lesser extent, in the stratum corneum (up to 0.130 µg/cm2) with a flux of permeation of 3.52 ± 4.5 µg/cm2/hour and lag time of 2.3 ± 1.3 h, after cutaneous exposure of temple tip into 1.0 mL artificial sweat for 24 h. Our study highlights the importance of avoiding the use of Be alloys in items following long-term skin contact.

Percutaneous metals absorption following exposure to road dust powder.

The skin constitutes a protective barrier to external physical and chemical aggressions. Although it is constantly exposed to various xenobiotics, it is generally considered poorly permeable to them, as for example metal ions, becoming unfortunately an entry route of such substances. Metals may penetrate inside the skin inducing more or less local effects such as skin sensitization and potential metals diffusion into the bloodstream. The objective of the study was to investigate the percutaneous penetration of metals in vitro - ex vivo in Franz cell with intact as well damaged skin applying a road dust powder. Moreover, porcine and human skins were compared. This study demonstrated that, after the application of a road dust powder on the skin, metals can penetrate and permeate this cutaneous membrane. From this experimental analysis, in intact skin lead (Pb) achieved the highest skin absorption in both human and porcine skin, while skin absorption profile of cobalt (Co) was the lowest in human skin than the one in porcine model. The concentrations of Ni present in receiving solution were higher compared to other metals in all experiments performed. The present work, definitely shows that metals permeation through damaged skin is accelerated than intact skin, as a result of the weaker cutaneous barrier function. According to published data, pig skin appeared as a suitable model for human skin. Our results confirmed that skin absorption of metals can be relevant in environmental exposures.

Cyclodipeptides: From Their Green Synthesis to Anti-Age Activity.

Cyclodipeptides (CDPs) or diketopiperazines (DKPs) are often found in nature and in foodstuff and beverages and have attracted great interest for their bioactivities, biocompatibility, and biodegradability. In the laboratory, they can be prepared by green procedures, such as microwave-assisted cyclization of linear dipeptides in water, as performed in this study. In particular, five CDPs were prepared and characterized by a variety of methods, including NMR and ESI-MS spectroscopies and single-crystal X-ray diffraction (XRD), and their cytocompatibility and anti-aging activity was tested in vitro, as well as their ability to penetrate the different layers of the skin. Although their mechanism of action remains to be elucidated, this proof-of-concept study lays the basis for their future use in anti-age cosmetic applications.

Influence of start-up phase of an incinerator on inorganic composition and lead isotope ratios of the atmospheric PM10.

A municipal solid waste incinerator (MSWI) was installed in a peripheral area of the city of Turin. In this study, we evaluated the contribution of this plant to the massive concentration of PM10, to its chemical composition and to the distribution of the lead isotopes during the start-up phase.We assessed the inorganic composition of PM10 collected in the vicinity of the Turin incinerator by inductively coupled plasma atomic emission spectroscopy (ICP-AES), magnetic sector inductively coupled plasma mass spectrometer (SF-ICP-MS) and ion chromatography (IC). The lead isotope ratios in PM10 samples were determined by SF-ICP-MS by a method developed and optimized using experimental design approach. Element trends and data chemometric treatment evidence that the vehicular traffic, increased in this area due to the opening of the MSWI plant, and, to a lesser degree, the direct incinerator emissions influence As, Cd, Cr, Cu, Ba, Mo, Pb, Sn and Zn concentrations. As a whole, however, the element concentrations in PM10 and the Enrichment Factors (EFs) were comparable with the values reported for other urban sites and target pollutant concentrations of MSWI emissions, namely Cd, Cr, Cu and Pb, were lower than in PM10 emitted from older MSWIs. This confirms that incinerators of new installation have a lower impact on atmospheric PM10 composition thanks to stricter current legislation and up-to-date technologies. The lead isotope ratios investigation allowed to distinguish the diverse sources (crustal, vehicular traffic and MSWI) that influence lead concentration in PM10 collected near incinerator during start-up phase.

Use of single particle ICP-MS to estimate silver nanoparticle penetration through baby porcine mucosa.

Children are potentially exposed to products that contain nanoparticles (NPs). In particular, silver NPs are commonly present both in products used by and around children, primarily due to their antibacterial properties. However, very few data are available regarding the ability of silver NPs to penetrate through the oral mucosa in children. In the present work, we used baby porcine buccal mucosa mounted on vertical Franz diffusion cells, as an in vitro model to investigate penetration of silver NPs (19 ± 5 nm). Permeability experiments were performed using pristine physiologically-relevant saline solution in the receiver chamber and known concentrations of NPs or ions in the donor chamber; conditions mimicked the in vivo physiological pH conditions. After physicochemical characterization of silver nanoparticles dispersed in physiological solution, we evaluated the passage of ions and NPs through the mucosa, using single particle inductively coupled plasma mass spectrometry. A flux of 4.1 ± 1.7 ng cm-2 min-1 and a lag time of 159 ± 17 min were observed through mucosa exposed to silver nanoparticles. The latter suggests nanoparticle penetration through the baby porcine mucosa and release Ag+ ions in the receptor fluid, as confirmed by computational model. Due to physiological similarity between human and pig membranes it is reasonable to assume that a trans-oral mucosa penetration could occur in children upon contact with silver nanoparticles.

A multidisciplinary study unveils the nature of a Roman ink of the I century AD.

A multi-instrumental approach combining highly sensitive Synchrotron Radiation-based techniques was used to provide information on the real composition of a dry black ink powder found in a bronze inkwell of the first century AD. The presence of Pb, Cu and Fe in the powder, revealed by XRF and ICP-OES data, leads to raise several hypotheses on their origin. The inkpot and its lid were also investigated by Hand-Held XRF, revealing a bronze alloy (Cu-Sn) with a certain amount of Fe and Pb. The lid was found to be particularly enriched in lead. XRPD, XAS and FTIR measurements showed a substantial presence of silicates and common clay minerals in the ink along with cerussite and malachite, Pb and Cu bearing-carbonates, respectively. These evidences support the hypothesis of an important contamination of the ink sample by the burial environment (soil) and the presence of degradation products of the bronze inkpot. The combined use of IR, Raman, and GC-MS evidenced that the black ink is mainly composed of amorphous carbon deriving from the combustion of organic material mixed with a natural binding agent, Arabic gum.

CuO(x)-TiO2 photocatalysts for H2 production from ethanol and glycerol solutions.

Hydrogen production by photocatalytic reforming of aqueous solutions of ethanol and glycerol was studied with the use of impregnated and embedded CuO(x)/TiO(2) photocatalysts. Embedded CuO(x)@TiO(2) was prepared by a water-in-oil microemulsion method, which consists in the formation of Cu nanoparticles in the microemulsion followed by controlled hydrolysis and condensation of tetraisopropyl orthotitanate with the aim of covering the protected metal particles with a surrounding layer of porous titanium oxyhydroxide. Mild calcination leads to the complete removal of the organic residues, the crystallization of TiO(2), and an unavoidable oxidation of copper. Two reference samples were prepared by classical wet impregnation of preformed TiO(2) with different ratios of anatase, rutile, and brookite polymorphs. The two supports were prepared by sol-gel (TiO(2)-SG) and microemulsion (TiO(2)-ME) methods. Superior performances have been observed for the embedded system, which shows higher hydrogen production rates with respect to the impregnated systems using either ethanol or glycerol as sacrificial molecules. Deep structural characterization of the materials has been performed by coupling high resolution transmission electron microscopy (HRTEM), high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), X-ray absorption fine structure (XAFS), and electron paramagnetic resonance (EPR) techniques. Correlation between copper oxidation state and its dispersion and reactivity has been attempted. Finally, the stability of the CuO(x)/TiO(2) catalysts was also studied with respect to carbonaceous deposits and copper leaching.

Trace elements in the estuarine systems of the Gulf of Trieste (northern Adriatic Sea): A chemometric approach to depict partitioning and behaviour of particulate, colloidal and truly dissolved fractions.

Estuaries are transitional water systems where the hydrodynamic processes governing water circulation actively influence suspended particle transport and deposition. In the estuarine mixing zone, the strong physico-chemical gradients resulting from the interaction between river freshwater and seawater may affect the distribution, mobility and fate of several potentially toxic compounds, among which trace elements are of major concern. Knowledge regarding the partitioning behaviour of trace elements would provide essential scientific support for the environmental management of estuaries. In this study, trace element occurrence and phase partitioning among suspended particulate matter, colloidal material and the truly dissolved fraction were investigated in the main Italian and Slovenian estuarine environments of the Gulf of Trieste (northern Adriatic Sea). Further information about the water quality at the river mouths was provided and, in addition to the traditional evaluation of single chemical parameters, a multi-way principal component analysis was employed in order to depict disparities among sampling sites, water layers and seasonal conditions with the final aim of evaluating trace element phase partitioning. Results indicated that the suspended particulate matter acts as the main effective vehicle for Cu, Cr, Fe, Ni and Pb, and enhanced adsorption processes resulted in elevated partitioning coefficients, especially for Fe and Pb. Although disparities occurred between sampling sites and seasons, trace elements showing affinity for the solid phase appeared to be partially bound to the colloidal material. Conversely, As and Cs prevailed in the truly dissolved fraction, especially in seawater and showed scarce affinity for both the suspended particles and colloids.

Nanotechnology-Based Cisplatin Intracellular Delivery to Enhance Chemo-Sensitivity of Ovarian Cancer.

BACKGROUND: Platinum resistance is a major challenge in the management of ovarian cancer. Even low levels of acquired resistance at the cellular level lead to impaired response to cisplatin. In ovarian cancer intraperitoneal therapy, nanoparticle formulation can improve the cisplatin's pharmacokinetics and safety profile. PURPOSE: This work aimed to investigate the chemo-sensitivity of ovarian cancer SKOV3 cells upon short-term (72h) single treatment of cisplatin and cisplatin-loaded biodegradable nanoparticles (Cis-NP). The aim was then to determine the therapeutic properties of Cis-NP in vivo using a SKOV3-luc cells' xenograft model in mice. METHODS: Cell cytotoxicity was assessed after the exposure of the cell culture to cisplatin or Cis-NP. The effect of treatments on EMT and CSC-like phenotype was studied by analyzing a panel of markers by flow cytometry. Intracellular platinum concentration was determined by inductively coupled plasma mass spectrometry (ICS-MS), and gene expression was evaluated by RNAseq analysis. The efficacy of intraperitoneal chemotherapy was evaluated in a SKOV3-luc cells' xenograft model in mice, through a combination of bioluminescence imaging, histological, and immunohistochemical analyses. RESULTS: We observed in vitro that short-term treatment of cisplatin has a critical role in determining the potential induction of chemoresistance, and a nanotechnology-based drug delivery system can modulate it. The RNAseq analysis underlines a protective effect of nanoparticle system according to their ability to down-regulate several genes involved in chemoresistance, cell proliferation, and apoptosis. The highest intracellular platinum concentration obtained with Cis-NP treatment significantly improved the efficacy. Consistent with in vitro results, we found that Cis-NP treatment in vivo can significantly reduce tumor burden and aggressiveness compared to the free drug. CONCLUSION: Nanoparticle-mediated cisplatin delivery may serve as an intracellular depot impacting the cisplatin pharmacodynamic performance at cellular levels. These features may contribute to improving the drawbacks of conventional intraperitoneal therapy, and therefore will require further investigations in vivo.