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Two drugs already approved by the U.S. Food and Drug Administration and the European Medicinal Agency combined in a dinuclear Pt(ii) complex.

The proposed PPy-MIP modified electrode was able to detect dimethoate in the picomolar range (LOD of (8 ± 2) × 10−12 M), which is five orders of magnitude lower than the limits set by EU legislation (i.e., ∼40 × 10−9 M).

MnO x -TiO2 catalysts (0, 1, 5, and 10 wt % Mn nominal content) for NH3-SCR (selective catalytic reduction) of NO x have been synthesized by the reverse micelle-assisted sol-gel procedure, with the aim of improving the dispersion of the active phase, usually poor when obtained by other synthesis methods (e.g., impregnation) and thereby lowering its amount. For comparison, a sample at nominal 10 wt % Mn was obtained by impregnation of the (undoped) TiO2 sample. The catalysts were characterized by using an integrated multitechnique approach, encompassing X-ray diffraction followed by Rietveld refinement, micro-Raman spectroscopy, N2 isotherm measurement at -196 °C, energy-dispersive X-ray analysis, diffuse reflectance UV-vis spectroscopy, temperature-programmed reduction technique, and X-ray photoelectron spectroscopy. The obtained results prove that the reverse micelle sol-gel approach allowed for enhancing the catalytic activity, in that the catalysts were active in a broad temperature range at a substantially low Mn loading, as compared to the impregnated catalyst. Particularly, the 5 wt % Mn catalyst showed the best NH3-SCR activity in terms of both NO x conversion (ca. 90%) and the amount of produced N2O (ca. 50 ppm) in the 200-250 °C temperature range.

Six enantiomerically pure, oxaliplatin-like, platinum compounds (two platinum(II) and four platinum(IV)), all containing unsaturated cyclic diamine trans-1,2-diamino-4-cyclohexene (DACHEX) as a substitute for the trans-1,2-diaminocyclohexane used in oxaliplatin, were investigated. The complexes were characterized by elemental analyses, ESI-MS, and 1H-NMR spectroscopy. For the four Pt(IV) complexes the electrochemical redox behaviour, investigated by cyclic voltammetry, showed that all complexes possess reduction potentials suitable for activation in vivo. The antiproliferative activity was assessed in vitro on human cancer cell lines, also selected for resistance to platinum-based drugs or belonging to the MultiDrug-Resistant (MDR) phenotype. All complexes exhibited antiproliferative activity superior to that of cisplatin and almost equivalent to or better than that of oxaliplatin; moreover, most complexes were also capable of overcoming both the cisplatin- and the oxaliplatin-resistance. By comparing the effectiveness of the enantiomerically pure compounds with the racemic one, the R,R enantiomer emerged as the most effective in the case of Pt(II) complexes whereas the S,S enantiomer was the most effective in the case of the Pt(IV) derivatives. From the results obtained also against 3D spheroid tumor models, cis,trans,cis-[Pt(OXA)(OBz)2(1S,2S-DACHEX)] (OBz = benzoate) emerged as the most promising candidate for further preclinical investigation.

Semiconductor materials are the basis of electronic devices employed in the communication and media industry. In the present work, we report the synthesis and characterization of mixed metal oxides (MOs) as p,n-junction photocatalysts, and demonstrate the correlation between the preparation technique and the properties of the materials. Solid-state UV-visible diffuse reflectance spectroscopy (UV-VIS DRS) allowed for the determination of the light absorption properties and the optical energy gap. X-ray photoelectron spectroscopy (XPS) allowed for the determination of the surface speciation and composition and for the determination of the valence band edge. The opto-electronic behavior was evaluated measuring the photocurrent generated after absorption of chopped visible light in a 3-electrode cell. Scanning electron microscopy (SEM) measurements allowed for auxiliary characterization of size and morphology, showing the formation of composites for the ternary Cu2O-In2O3 p,n-mixed oxide, and even more for the quaternary Cu2O-In2O3-TiO2 MO. Light absorption spectra and photocurrent-time curves mainly depend upon the composition of MOs, while the optical energy gap and defective absorption tail are closely related to the preparation methodology, time and thermal treatment. Qualitative electronic band structures of semiconductors are also presented.

Replacing fossil-C based plastics with those derived from renewable-C is one of the goals of the modern polymer industry. 2,5-Furan dicarboxylic acid (2,5-FDCA) is a candidate to substitute terephthalic acid as comonomer for polyesters. 2,5-FDCA is usually produced from C6 sugars. Carboxylation of 2-furancarboxylic acid (2-FCA) to 2,5-FDCA is an alternative synthetic approach to such monomer for polyethene furoate (PEF) preparation. In this work, several inorganic carbonates have been tested in the 2-FCA carboxylation in presence and absence of CO2. A key copper intermediate has been synthesized and fully characterized that is able to increase the acidity and, thus, the reactivity of 5-H towards a carbonate species. Carboxylation occurs at 93% yield in absence of CO2. The role of metal salts and CO2 were investigated. The conversion yield of 2-FCA into the dicarboxylic acid is related to the charge density on the metal cation, increasing with lower charge-density.

The emerging problem of the antibiotic resistance development and the consequences that the health, food and other sectors face stimulate researchers to find safe and effective alternative methods to fight antimicrobial resistance (AMR) and biofilm formation. One of the most promising and efficient groups of materials known for robust antimicrobial performance is noble metal nanoparticles. Notably, silver nanoparticles (AgNPs) have been already widely investigated and applied as antimicrobial agents. However, it has been proposed to create synergistic composites, because pathogens can find their way to develop resistance against metal nanophases; therefore, it could be important to strengthen and secure their antipathogen potency. These complex materials are comprised of individual components with intrinsic antimicrobial action against a wide range of pathogens. One part consists of inorganic AgNPs, and the other, of active organic molecules with pronounced germicidal effects: both phases complement each other, and the effect might just be the sum of the individual effects, or it can be reinforced by the simultaneous application. Many organic molecules have been proposed as potential candidates and successfully united with inorganic counterparts: polysaccharides, with chitosan being the most used component; phenols and organic acids; and peptides and other agents of animal and synthetic origin. In this review, we overview the available literature and critically discuss the findings, including the mechanisms of action, efficacy and application of the silver-based synergistic antimicrobial composites. Hence, we provide a structured summary of the current state of the research direction and give an opinion on perspectives on the development of hybrid Ag-based nanoantimicrobials (NAMs).

Background: The blood–brain barrier (BBB) bypass of dopamine (DA) is still a challenge for supplying it to the neurons of Substantia Nigra mainly affected by Parkinson disease. DA prodrugs have been studied to cross the BBB, overcoming the limitations of DA hydrophilicity. Therefore, the aim of this work is the synthesis and preliminary characterization of an oxidized alginate-dopamine (AlgOX-DA) conjugate conceived for DA nose-to-brain delivery. Methods: A Schiff base was designed to connect oxidized polymeric backbone to DA and both AlgOX and AlgOX-DA were characterized in terms of Raman, XPS, FT-IR, and 1H- NMR spectroscopies, as well as in vitro mucoadhesive and release tests. Results: Data demonstrated that AlgOX-DA was the most mucoadhesive material among the tested ones and it released the neurotransmitter in simulated nasal fluid and in low amounts in phosphate buffer saline. Results also demonstrated the capability of scanning near-field optical microscopy to study the structural and fluorescence properties of AlgOX, fluorescently labeled with fluorescein isothiocyanate microstructures. Interestingly, in SH-SY5Y neuroblastoma cell line up to 100 μg/mL, no toxic effect was derived from AlgOX and AlgOX-DA in 24 h. Conclusions: Overall, the in vitro performances of AlgOX and AlgOX-DA conjugates seem to encourage further ex vivo and in vivo studies in view of nose-to-brain administration.

The urgency for the availability of new antibacterial/disinfectant agents has become a worldwide priority. At the same time, along with the extensive use of other metal nanoparticles (NPs), the investigation of magnetic NPs (MNPs) in antibacterial studies has turned out to be an increasingly attractive research field. In this context, we present the preparation and characterization of superparamagnetic iron oxide NPs, electrodecorated with antimicrobial copper NPs, able to modulate the release of bioactive species not only by the NP&rsquo, s stabilizer, but also through the application of a suitable magnetic field. Antimicrobial synergistic CuNPs stabilized by benzalkonium chloride have been used in the current study. We demonstrate the successful preparation of Cu@Fe3O4 MNPs composites through morphological and spectroscopic results. Additionally, an extensive magnetic characterization is reported, along with hyperthermia-induced copper ionic release. On the basis of our results, we propose a new generation of antimicrobial magnetic nanomaterials, whose bioactivity can be also tuned by the application of a magnetic field.

Kiteplatin, [PtCl2(cis-1,4-DACH)] (DACH = diaminocyclohexane), contains an isomeric form of the oxaliplatin diamine ligand trans-1R,2R-DACH and has been proposed as a valuable drug candidate against cisplatin- and oxaliplatin-resistant tumors, in particular, colorectal cancer. To further improve the activity of kiteplatin, it has been transformed into a Pt(IV) prodrug by the addition of two benzoato groups in the axial positions. The new compound, cis,trans,cis-[PtCl2(OBz)2(cis-1,4-DACH)] (1; OBz = benzoate), showed cytotoxic activity at nanomolar concentration against a wide panel of human cancer cell lines. Based on these very promising results, the investigation has been extended to the in vivo activity of compound 1 in a Lewis Lung Carcinoma (LLC) model and its suitability for oral administration. Compound 1 resulted to be remarkably stable in acidic conditions (pH 1.5 to mimic the stomach environment) undergoing a drop of the initial concentration to ~60% of the initial one only after 72 h incubation at 37 °C; thus resulting amenable for oral administration. Interestingly, in a murine model (2·106 LLC cells implanted i.m. into the right hind leg of 8-week old male and female C57BL mice), a comparable reduction of tumor mass (~75%) was observed by administering compound 1 by oral gavage and the standard drug cisplatin by intraperitoneal injection, thus indicating that, indeed, there is the possibility of oral administration for this dibenzoato prodrug of kiteplatin. Moreover, since the mechanism of action of Pt(IV) prodrugs involves an initial activation by chemical reduction to cytotoxic Pt(II) species, the reduction of 1 by two bioreductants (ascorbic acid/sodium ascorbate and glutathione) was investigated resulting to be rather slow (not complete after 120 h incubation at 37 °C). Finally, the neurotoxicity of 1 was evaluated using an in vitro assay.

Copper doped‐TiO2 (P25) nanomaterials have been intensively studied as promising catalysts for H2 production by photo‐reforming of selected organic compounds. However, the role of copper oxidation states on the improvement of photocatalytic activity is still debated. In this work, CuOx‐impregnated P25‐TiO2 catalysts were used for photocatalytic production of hydrogen from methanol. Copper species/oxidation states both in the as‐prepared catalysts and after the photocatalytic process were investigated. To this purpose, H2 production rates were correlated to physico‐chemical properties of the samples, both before and after photocatalytic process, by means of Raman, X‐Ray Diffraction, Electron Paramagnetic Resonance spectroscopy, X‐Ray Photoelectron Spectroscopy, Temperature‐Programmed Reduction and High Resolution Transmission Electron Microscope techniques. Results revealed the presence of both Cu2O and CuO deposits on the samples surface after calcination. Notably, under near‐UV irradiation, the fraction of highly dispersed CuO particles undergo a partial dissolution process, followed by reduction to metallic copper Cu(s) by photogenerated electrons, boosting H2 production rate. Our findings indicate that both Cu2O and Cu(s) act as co‐catalysts for H2 generation, yet by different mechanisms. Overall this study, provides the basis to enhance catalytic performance of red‐ox active systems through UV‐irradiation approach.

In the present paper, we report the synthesis and characterization of both binary (Cu2O, Fe2O3, and In2O3) and ternary (Cu2O-Fe2O3 and Cu2O-In2O3) transition metal mixed-oxides that may find application as photocatalysts for solar driven CO2 conversion into energy rich species. Two different preparation techniques (High Energy Milling (HEM) and Co-Precipitation (CP)) are compared and materials properties are studied by means of a variety of characterization and analytical techniques UV-Visible Diffuse Reflectance Spectroscopy (UV-VIS DRS), X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Energy Dispersive X-Ray spectrometry (EDX). Appropriate data elaboration methods are used to extract materials bandgap for Cu2O@Fe2O3 and Cu2O@In2O3 prepared by HEM and CP, and foresee whether the newly prepared semiconductor mixed oxides pairs are useful for application in CO2-H2O coprocessing. The experimental results show that the synthetic technique influences the photoactivity of the materials that can correctly be foreseen on the basis of bandgap experimentally derived. Of the mixed oxides prepared and described in this work, only Cu2O@In2O3 shows positive results in CO2-H2O photo-co-processing. Preliminary results show that the composition and synthetic methodologies of mixed-oxides, the reactor geometry, the way of dispersing the photocatalyst sample, play a key role in the light driven reaction of CO2&ndash, H2O. This work is a rare case of full characterization of photo-materials, using UV-Visible DRS, XPS, XRD, TEM, EDX for the surface and bulk analytical characterization. Surface composition may not be the same of the bulk composition and plays a key role in photocatalysts behavior. We show that a full material knowledge is necessary for the correct forecast of their photocatalytic behavior, inferred from experimentally determined bandgaps.

Chitosan (CS), a natural non-toxic polysaccharide, shows intrinsic antimicrobial activity against a wide range of pathogens. CS and CS-based biomaterials can be effective additives in food and medicine-related industries to inhibit growth of pathogens. The application of inorganic nanophases, such as metal and metal oxide nanoparticles, has received attention due to their broad and pronounced antimicrobial activity. Upon combination with CS, which can act as stabilizer, with active inorganic nanophases, robust synergistic nanoantimicrobial (NAM) systems can be produced. These hybrid NAMs offer an alternative strategy to fight antimicrobial resistance and overcome limitations of conventional antibiotics. Bioactive ZnO, Cu and Ag nanophases produced by green electrochemical approach [Nanomaterials, 10(3) (2020), 473] and laser ablation in solution [(Coll. Surf. A, 559 (2018), 148-158), (Food packaging shelf, 22 (2019), 1000422)] can be combined with antimicrobial CS to develop synergistic antimicrobial nanohybrids with amplified biological action. CS-based NAMs were preliminary characterized by electron microscopies and spectroscopic techniques. Hybrid NAMs may find application in the control and inhibition of biofilm growth. AcknowledgementsFinancial support is acknowledged from European Union’s 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 813439

S. I. Hossain1,3,*, M. C. Sportelli1,2,3, R. A. Picca1,3, N. Ditaranto 1,3, N. Cioffi1,3 1Dipartimento di Chimica, Università degli Studi di Bari “Aldo Moro”, Bari, Italy; 2CNR, Istituto di Fotonica e Nanotecnologie UOS, Bari, Italy; 3CSGI (Center for Colloid and Surface Science) c/o Dept. Chemistry, via Orabona 4, 70125 Bari, Italy. Copper nanoparticles (CuNPs) are considered as potential antimicrobial agents due to their improved stability and safety, and longer active period than that of organic nanomaterials, with multi-targeted mechanism of action [1]. Nevertheless, metal NPs can suffer from agglomeration, reducing their antibacterial activity [2]. Cu incorporation in inorganic substrates such as metal oxides or montmorillonite (MMT) plays an important role due to the possibilities of creating an antibacterial nanomaterial with slow release of Cu species in order to obtain a prolonged antibacterial activity. Therefore, CuNPs were synthesized via a rapid electrochemical method using the inorganic micro-powders as carrier. Characterization studies on the nanocomposite were done by Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The as-prepared Cu-based nanocomposites could be employed for inhibiting the growth of biofilms. References Nanotechnology 25, (2014), 135101 ACS Appl. Mater. Interfaces 4, (2012), 178–184 Acknowledgements "Financial support is acknowledged from European Union’s 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 813439."

In the present study we have studied the incorporation and release of selenite ions (SeO32−) in hydroxyapatite nanoparticles for the treatment of bone tumors. Two types of selenium-doped hydroxyapatite (HASe) nanoparticles (NPs) with a nominal Se/(P + Se) molar ratio ranging from 0.01 up to 0.40 have been synthesized by a new and mild wet method. The two series of samples were thoroughly characterized and resulted to be slightly different in chemical composition, but they had similar properties in terms of morphology and degree of crystallinity. Selenium release from HASe was investigated under neutral and acidic conditions to simulate both healthy tissues and the low-pH environment surrounding a tumor mass, respectively. The comparison of the release profiles at two pH values clearly showed the possibility of modulating the Se release by simply changing the amount of Se in the HASe particles. The correlation between the physicochemical properties of HASe and their dissolution as a function of pH has been also investigated to facilitate future application of the NPs as chemotherapeutic adjuvant agents. Finally, the cytotoxic activity of HASe was evaluated using prostate (PC3) and breast (MDA-MB-231) cancer cells as well as healthy human bone marrow stem cells (hBMSc). HASe NPs exerted a good cytocompatibility at low concentration of Se but, with high Se doping concentration, they displayed strong cytotoxicity.

Six platinum(IV) compounds derived from an oxaliplatin analogue containing the unsaturated cyclic diamine trans-1,2-diamino-4-cyclohexene (DACHEX), in place of the 1,2-diaminocyclohexane, and a range of axial ligands, were synthesized and characterized. The derivatives with at least one axial chlorido ligand demonstrated solvent-assisted photoreduction. The electrochemical redox behavior was investigated by cyclic voltammetry, all compounds showed reduction potentials suitable for activation in vivo. X-ray photoelectron spectroscopy (XPS) data indicated an X-ray-induced surface reduction of the Pt(IV) substrates, which correlates with the reduction potentials measured by cyclic voltammetry. The cytotoxic activity was assessed in vitro on a panel of human cancer cell lines, also including oxaliplatin-resistant cancer cells, and compared with that of the reference compounds cisplatin and oxaliplatin, all IC50 values were remarkably lower than those elicited by cisplatin and somewhat lower than those of oxaliplatin. Compared to the other Pt(IV) compounds of the series, the bis-benzoate derivative was by far (5&ndash, 8 times) the most cytotoxic showing that low reduction potential and high lipophilicity are essential for good cytotoxicity. Interestingly, all the complexes proved to be more active than cisplatin and oxaliplatin even in three-dimensional spheroids of A431 human cervical cancer cells.

Several three-terminal organic bioelectronic structures have been proposed so far to address the needs for a variety of biosensing applications. The most popular ones utilized organic field-effect transistors operated in an electrolyte, to detect both proteins and genomic analytes. They are endowed with selectivity by immobilizing a layer of bio-recognition elements. These features along with the foreseen low-cost for their production, make them very appealing for point-of-care biomedical applications. However, organic bioelectronic transistors do not always exhibit a performance level beyond state-of-the-art electrochemical sensors, which have been dominating the field for decades. This review offers a perspective view based on a systematic comparison between the potentiometric and amperometric electrochemical sensors and their organic bioelectronic transistor counterparts. The key-relevant aspects of the sensing mechanisms are reviewed for both, and when the mathematical analytical expression is actually available, the amplification factors are reported as the ratio between the response of a rationally designed transistor (or amplifying circuit) and that of a homologous electrochemical sensor. The functional dependence of the bioelectronic sensor responses on the concentration of the species to be detected enabling their correct analytical quantification, is also addressed.

A characterization of solid lipid nanoparticles (SLN) produced starting from an emulsion prepared in acidic or neutral medium and based on Gelucire® 50/13 as lipid phase was performed by X-Ray Photoelectron Spectroscopy Analysis (XPS). The smallest particle size and the highest peptide content were observed for GSH-SLN produced in acidic medium [GSH-SLN(HAc)]. XPS analysis demonstrate the absence of GSH from the surface of the SLN and, combined with the observed sustained release kinetics, allowed us to propose the peptide GSH localization within the lipid nanoparticles. Differential Scanning Calorimetry thermograms of the GSH loaded SLN revealed the absence of the melting point peak at 193 °C attributable to the peptide, suggesting the decreased crystallinity of GSH in the lipid Gelucire® 50/13 forming the SLN matrix. SAF-1 cells (fibroblast-like cells derived from the fin) and gilthead seabream leukocytes were incubated in the presence of FITC-SLN. However, confocal microscopy confirmed that both types of cells were unable to internalize SLN. This result may be ascribed to the slightly negative surface-charge of labelled particles which is unfavorable for effective interactions of these essentially neutral particles with fish cells, suggesting, in perspective, the need to modify the carrier system surface in order to target cell fish.

The Pt(IV) prodrug of kiteplatin, cis-trans-cis-[PtCl2(RS-Ibuprofen-H)2(cis-1,4-DACH)], having in the axial positions two molecules of Ibuprofen, has been synthesised, characterized and tested in vitro. The aim was to potentiate the cytotoxic effect of kiteplatin with the anti-inflammatory activity of Ibuprofen. The reduction potential of the conjugate resulted comparable to those of other reported Pt(IV) carboxylate complexes, ensuring in vivo stability in blood during transport and intracellular reduction with release of the active species. The cytotoxic activity of the complex resulted remarkably potentiated reaching nanomolar activity. It is possible that the coordinated Ibuprofen molecules promote the transport and the accumulation of the complex in tumor cells by increasing its lipophilicity. In addition to the increased uptake, Ibuprofen could also exert an anti-inflammatory action mediated by inhibition of the COX enzymes which are overexpressed in tumors. The use of a conjugate with Pt-bound Ibuprofen can ensure similar cellular uptake and biodistribution for both the anti-inflammatory and the cytotoxic drugs in the exact ratio of 2:1.

The rapid spreading of resistance among common bacterial pathogens towards the misused antibiotics/disinfectant agents has drawn much attention worldwide to bacterial infections. In light of this, the present work aimed at the realization of core&ndash, shell nanoparticles possessing remarkable antimicrobial properties thanks to the synergistic action of the metal core and the disinfectant shell. Copper nanoparticles stabilized by benzalkonium chloride were prepared, characterized, and implemented in poly-vinyl-methyl ketone to obtain nanoantimicrobial composite coatings. Bioactivity tests are reported, proving the excellent disinfectant properties of the proposed nanomaterials, as compared to one of the well-known and strongest silver-based nanoantimicrobials. Applications are also briefly described.

TiO2 nanoparticles containing 0.0, 1.0, 5.0, and 10.0 wt.% Mo were prepared by a reverse micelle template assisted sol&ndash, gel method allowing the dispersion of Mo atoms in the TiO2 matrix. Their textural and surface properties were characterized by means of X-ray powder diffraction, micro-Raman spectroscopy, N2 adsorption/desorption isotherms at &minus, 196 &deg, C, energy dispersive X-ray analysis coupled to field emission scanning electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance UV&ndash, Vis spectroscopy, and &zeta, potential measurement. The photocatalytic degradation of Rhodamine B (under visible light and low irradiance) in water was used as a test reaction as well. The ensemble of the obtained experimental results was analyzed in order to discover the actual state of Mo in the final materials, showing the occurrence of both bulk doping and Mo surface species, with progressive segregation of MoOx species occurring only at a higher Mo content.

TiO2 nanoparticles containing 0.0, 1.0, 5.0, and 10.0 wt.% Mo were prepared by a reverse micelle template assisted sol–gel method allowing the dispersion of Mo atoms in the TiO2 matrix. Their textural and surface properties were characterized by means of X-ray powder diffraction, micro-Raman spectroscopy, N2 adsorption/desorption isotherms at −196 °C, energy dispersive X-ray analysis coupled to field emission scanning electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance UV–Vis spectroscopy, and ζ-potential measurement. The photocatalytic degradation of Rhodamine B (under visible light and low irradiance) in water was used as a test reaction as well. The ensemble of the obtained experimental results was analyzed in order to discover the actual state of Mo in the final materials, showing the occurrence of both bulk doping and Mo surface species, with progressive segregation of MoOx species occurring only at a higher Mo content.

In this paper we report the synthesis and characterization of the complex c,t,c-[Pt(dihydrogenpyrophosphate)(OH)2(cis-1,4-DACH)] (2), a Pt(IV) derivative of kiteplatin, which could be characterized by high bone tropism (due to the pyrophosphate ligand), enough stability to be administered orally, and activatable at the tumor site where the strong reduction conditions can promote its reduction to the corresponding Pt(II) counterpart with known cytotoxic activity. The new complex was characterized by ESI-MS, multinuclear NMR, X-Ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). 2 is very soluble in aqueous environment, very stable at physiological pH and quite stable also in acidic conditions with the possibility of oral administration. The in vitro cytotoxicity assays, performed against a panel of four human cancer cell lines, have shown that complex 2 has a cytotoxic activity comparable to that of cisplatin and slightly lower than that of kiteplatin and the pyrophosphate Pt(II) precursor. This behavior can be attributed to its reduced ability to enter cancer cells. However, the cytotoxic activity of 2 is very promising considering that generally Pt(IV) complexes have IC50 values greater than those of the Pt(II) counterparts.

In the last decades, most attention has been paid to solid lipid nanoparticles (SLN) as nanocarriers for pharmaceutical purposes due to their low toxicity, possible production on large scale and delivery of active principles by several administration routes. For example, lung delivery will necessitate direct administration, e.g. by aerosolisation, to maximize deposition into the airways and minimize systemic side effects. However, SLN based on common solid lipids preferentially incorporate lipophilic drugs, while the hydrophilic ones are loaded in low amount. To overcome this drawback, it seemed interesting to evaluate SLN based on self-emulsifying (SE) lipids, which are mixtures of lipids, surfactant and cosurfactants able to form emulsions in contact with aqueous media. Thus, we evaluated the preparation of SLN based on Gelucire® 50/13, selected as a SE lipid model, encapsulating glutathione (GSH) or proanthocyanidins occurring in grape seed extract (GSE), as hydrophilic model substances according to the melt-emulsification method. The encapsulation efficiency of such GSH- or GSE-SLN resulted satisfactory for both the hydrophilic compounds examined. However, to draw definitive conclusions on the scope and limitations of this approach based on SE lipids, further studies are necessary. Moreover, GSH- SLN were investigated for their performance in delivering the antioxidant peptide to immunocompetent fish cells, while GSE-SLN were evaluated for their possible application in the treatment of pulmonary diseases. It was found that GSH-SLN were not internalized by fish cells, while GSE-SLN showed favorable properties for lung delivery.In the last decades, most attention has been paid to solid lipid nanoparticles (SLN) as nanocarriers for pharmaceutical purposes due to their low toxicity, possible production on large scale and delivery of active principles by several administration routes. For example, lung delivery will necessitate direct administration, e.g. by aerosolisation, to maximize deposition into the airways and minimize systemic side effects. However, SLN based on common solid lipids preferentially incorporate lipophilic drugs, while the hydrophilic ones are loaded in low amount. To overcome this drawback, it seemed interesting to evaluate SLN based on self-emulsifying (SE) lipids, which are mixtures of lipids, surfactant and cosurfactants able to form emulsions in contact with aqueous media. Thus, we evaluated the preparation of SLN based on Gelucire® 50/13, selected as a SE lipid model, encapsulating glutathione (GSH) or proanthocyanidins occurring in grape seed extract (GSE), as hydrophilic model substances according to th...

Copper nanoparticles (CuNPs) stabilized by quaternary ammonium salts are well known as antimicrobial agents. The aim of this work was to study the feasibility of the inclusion of CuNPs in nanovesicular systems. Liposomes are nanovesicles (NVs) made with phospholipids and are traditionally used as delivery vehicles because phospholipids favor cellular uptake. Their capacity for hydrophilic/hydrophobic balance and carrier capacity could be advantageous to prepare novel hybrid nanostructures based on metal NPs (Me-NPs). In this work, NVs were loaded with CuNPs, which have been reported to have a biofilm inhibition effect. These hybrid materials could improve the effect of conventional antibacterial agents. CuNPs were electro-synthesized by the sacrificial anode electrolysis technique in organic media and characterized in terms of morphology through transmission electron microscopy (TEM). The NVs were prepared by the thin film hydration method in aqueous media, using phosphatidylcholine (PC) and cholesterol as a membrane stabilizer. The nanohybrid systems were purified to remove non-encapsulated NPs. The size distribution, morphology and stability of the NV systems were studied. Different quaternary ammonium salts in vesicular systems made of PC were tested as stabilizing surfactants for the synthesis and inclusion of CuNPs. The entrapment of charged metal NPs was demonstrated. NPs attached preferably to the membrane, probably due to the attraction of their hydrophobic shell to the phospholipid bilayers. The high affinity between benzyl-dimethyl-hexadecyl-ammonium chloride (BDHAC) and PC allowed us to obtain stable hybrid NVs c.a. 700 nm in diameter. The stability of liposomes increased with NP loading, suggesting a charge-stabilization effect in a novel antibiofilm nanohybrid material.