Publications by authors named "Jesus Santamaria"

101 Publications

Nondestructive production of exosomes loaded with ultrathin palladium nanosheets for targeted bio-orthogonal catalysis.

Nat Protoc 2021 01 27;16(1):131-163. Epub 2020 Nov 27.

Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, Zaragoza, Spain.

The use of exosomes as selective delivery vehicles of therapeutic agents, such as drugs or hyperthermia-capable nanoparticles, is being intensely investigated on account of their preferential tropism toward their parental cells. However, the methods used to introduce a therapeutic load inside exosomes often involve disruption of their membrane, which may jeopardize their targeting capabilities, attributed to their surface integrins. On the other hand, in recent years bio-orthogonal catalysis has emerged as a new tool with a myriad of potential applications in medicine. These bio-orthogonal processes, often based on Pd-catalyzed chemistry, would benefit from systems capable of delivering the catalyst to target cells. It is therefore highly attractive to combine the targeting capabilities of exosomes and the bio-orthogonal potential of Pd nanoparticles to create new therapeutic vectors. In this protocol, we provide detailed information on an efficient procedure to achieve a high load of catalytically active Pd nanosheets inside exosomes, without disrupting their membranes. The protocol involves a multistage process in which exosomes are first harvested, subjected to impregnation with a Pd salt precursor followed by a mild reduction process using gas-phase CO, which acts as both a reducing and growth-directing agent to produce the desired nanosheets. The technology is scalable, and the protocol can be conducted by any researcher having basic biology and chemistry skills in ~3 d.
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http://dx.doi.org/10.1038/s41596-020-00406-zDOI Listing
January 2021

Covalent Cross-Linking of 2H-MoS Nanosheets.

Chemistry 2021 Feb 12;27(9):2993-2996. Epub 2021 Jan 12.

IMDEA Nanociencia, C/Faraday 9 Ciudad Universitaria de Cantoblanco, 28049, Madrid, Spain.

The combination of 2D materials opens a wide range of possibilities to create new-generation structures with multiple applications. Covalently cross-linked approaches are a ground-breaking strategy for the formation of homo or heterostructures made by design. However, the covalent assembly of transition metal dichalcogenides flakes is relatively underexplored. Here, a simple covalent cross-linking method to build 2H-MoS -MoS homostructures is described, using commercially available bismaleimides. These assemblies are mainly connected vertically, basal plane to basal plane, creating specific molecular sized spaces between MoS sheets. Therefore, this straightforward approach gives access to the controlled connection of sulfide-based 2D materials.
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http://dx.doi.org/10.1002/chem.202004366DOI Listing
February 2021

Isolation of exosomes from whole blood by a new microfluidic device: proof of concept application in the diagnosis and monitoring of pancreatic cancer.

J Nanobiotechnology 2020 Oct 22;18(1):150. Epub 2020 Oct 22.

Department of Chemical Engineering, University of Zaragoza, 50018, Zaragoza, Spain.

Background: Exosomes are endocytic-extracellular vesicles with a diameter around 100 nm that play an essential role on the communication between cells. In fact, they have been proposed as candidates for the diagnosis and the monitoring of different pathologies (such as Parkinson, Alzheimer, diabetes, cardiac damage, infection diseases or cancer).

Results: In this study, magnetic nanoparticles (FeONPs) were successfully functionalized with an exosome-binding antibody (anti-CD9) to mediate the magnetic capture in a microdevice. This was carried out under flow in a 1.6 mm (outer diameter) microchannel whose wall was in contact with a set of NdFeB permanent magnets, giving a high magnetic field across the channel diameter that allowed exosome separation with a high yield. To show the usefulness of the method, the direct capture of exosomes from whole blood of patients with pancreatic cancer (PC) was performed, as a proof of concept. The captured exosomes were then subjected to analysis of CA19-9, a protein often used to monitor PC patients.

Conclusions: Here, we describe a new microfluidic device and the procedure for the isolation of exosomes from whole blood, without any need of previous isolation steps, thereby facilitating translation to the clinic. The results show that, for the cases analyzed, the evaluation of CA19-9 in exosomes was highly sensitive, compared to serum samples.
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http://dx.doi.org/10.1186/s12951-020-00701-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7579907PMC
October 2020

Carbon and nitrogen isotopes to distinguish sources of sedimentary organic matter in a Caribbean estuary.

Isotopes Environ Health Stud 2020 Oct - Dec;56(5-6):654-672. Epub 2020 Sep 30.

Centro de Estudios Ambientales de Cienfuegos (CEAC), Cienfuegos, Cuba.

Carbon and nitrogen stable isotope compositions (δ13C and δ15N) of organic matter (OM) and total organic carbon to total nitrogen ratio (Corg/TN) in a sediment core collected in Sagua estuary (Cuba), were investigated to elucidate the origin of the Sedimentary OM (SOM) and changes in its main sources, over the last 100 years. Results showed almost constant values in the elemental and isotope composition of SOM from 1908 to 1970 with an abrupt change after 1970. From 1970 to 2005, δ13C increased from -21.2 up to -19.3 ‰, while δ15N declined from 1.5 to values close to 0 ‰. The output of the mass-balance model for the identification of OM sources indicated that δ13C and Corg/TN values are generally influenced by marine Particulate OM (POM) sources. Between 1900 and 1970, the main OM source in sediments was marine POM (>85 %), with freshwater POM contributing ca. 15%. Since 1970, the establishment of the Alacranes Dam determined drastic environmental changes influencing the OM sources in the area. Mixing models pointed to seagrasses (79 %) as the main contributors to SOM in the first period, while since 1973 onward, the contribution of human-derived sources such as fertilizers and urban discharges became greater. This information can provide baseline data for the environmental management of the Sagua watershed.
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http://dx.doi.org/10.1080/10256016.2020.1819263DOI Listing
December 2020

Bioorthogonal Uncaging of Cytotoxic Paclitaxel through Pd Nanosheet-Hydrogel Frameworks.

J Med Chem 2020 09 17;63(17):9650-9659. Epub 2020 Aug 17.

Cancer Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road South, Edinburgh EH4 2XR, U.K.

The promising potential of bioorthogonal catalysis in biomedicine is inspiring incremental efforts to design strategies that regulate drug activity in living systems. To achieve this, it is not only essential to develop customized inactive prodrugs and biocompatible metal catalysts but also the right physical environment for them to interact and enable drug production under spatial and/or temporal control. Toward this goal, here, we report the first inactive precursor of the potent broad-spectrum anticancer drug paclitaxel (a.k.a. Taxol) that is stable in cell culture and labile to Pd catalysts. This new prodrug is effectively uncaged in cancer cell culture by Pd nanosheets captured within agarose and alginate hydrogels, providing a biodegradable catalytic framework to achieve controlled release of one of the most important chemotherapy drugs in medical practice. The compatibility of bioorthogonal catalysis and physical hydrogels opens up new opportunities to administer and modulate the mobility of transition metal catalysts in living environs.
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http://dx.doi.org/10.1021/acs.jmedchem.0c00781DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7497487PMC
September 2020

Controlled Covalent Functionalization of 2 H-MoS with Molecular or Polymeric Adlayers.

Chemistry 2020 May 31;26(29):6629-6634. Epub 2020 Mar 31.

IMDEA Nanociencia, Ciudad Universitaria de Cantoblanco, C/Faraday 9, 28049, Madrid, Spain.

Most air-stable 2D materials are relatively inert, which makes their chemical modification difficult. In particular, in the case of MoS , the semiconducting 2 H-MoS is much less reactive than its metallic counterpart, 1T-MoS . As a consequence, there are hardly any reliable methods for the covalent modification of 2 H-MoS . An ideal method for the chemical functionalization of such materials should be both mild, not requiring the introduction of a large number of defects, and versatile, allowing for the decoration with as many different functional groups as possible. Herein, a comprehensive study on the covalent functionalization of 2 H-MoS with maleimides is presented. The use of a base (Et N) leads to the in situ formation of a succinimide polymer layer, covalently connected to MoS . In contrast, in the absence of base, functionalization stops at the molecular level. Moreover, the functionalization protocol is mild (occurs at room temperature), fast (nearly complete in 1 h), and very flexible (11 different solvents and 10 different maleimides tested). In practical terms, the procedures described here allow for the chemist to manipulate 2 H-MoS in a very flexible way, decorating it with polymers or molecules, and with a wide range of functional groups for subsequent modification. Conceptually, the spurious formation of an organic polymer might be general to other methods of functionalization of 2D materials, where a large excess of molecular reagents is typically used.
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http://dx.doi.org/10.1002/chem.202000068DOI Listing
May 2020

Levels, spatial distribution, risk assessment, and sources of environmental contamination vectored by road dust in Cienfuegos (Cuba) revealed by chemical and C and N stable isotope compositions.

Environ Sci Pollut Res Int 2020 Jan 26;27(2):2184-2196. Epub 2019 Nov 26.

Geotop/Université du Québec à Montréal (UQAM), 201 Ave Président Kennedy, Montreal, QC, Canada.

Road dust is an indicator widely used when monitoring contamination and evaluating environmental and health risks in urban ecosystems. We conducted an exhaustive characterization of road dust samples coupling their chemical characteristics and stable isotope compositions (C and N) with the aim of evaluating the levels and spatial distribution of local contamination as well as to identify its main source(s) in the coastal city of Cienfuegos (Cuba). Results indicate that the concentrations of several elements (total nitrogen, S, Ca, V, Cu, Zn, Mo, Sn, Hg, and Pb) exceed the background values reported for both Cuban soils and the upper continental crust (UCC) and showed a high variability among the sampling sites. We show that road dust contamination in Cienfuegos induces high associated ecological risks. Among the studied elements, Cd and Hg are the major contributors to the environmental contamination in the city, mainly along busy roads and downtown. δC and δN, coupled to a multivariate statistical analysis, help associate the studied elements to several local sources of contamination: mineral matter derived from local soils, cement plant and related activities, road pavement alteration, power plant, road traffic, and resuspension of particulate organic matter (POM). Our results suggest that incorporating the chemical and isotope monitoring of road dust may help implement more effective environmental management measures in order to reduce their adverse impact on ecosystems and human health.
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http://dx.doi.org/10.1007/s11356-019-06783-7DOI Listing
January 2020

Cancer-derived exosomes loaded with ultrathin palladium nanosheets for targeted bioorthogonal catalysis.

Nat Catal 2019 Oct 9;2(10):864-872. Epub 2019 Sep 9.

Cancer Research UK Edinburgh Centre, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Crewe Road South, Edinburgh EH4 2XR, UK.

The transformational impact of bioorthogonal chemistries has inspired new strategies for the synthesis of bioactive agents through non-natural means. Among these, palladium (Pd) catalysts have played a prominent role in the growing subfield of bioorthogonal catalysis by producing xenobiotics and uncaging biomolecules in living systems. However, delivering catalysts selectively to specific cell types still lags behind catalyst development. Here we have developed a bio-artificial device consisting of cancer-derived exosomes loaded with Pd catalysts by a method that enables the controlled assembly of Pd nanosheets directly inside the vesicles. This hybrid system mediates Pd-triggered dealkylation reactions and inside cells and displays preferential tropism for their progenitor cells. The use of Trojan exosomes to deliver abiotic catalysts into designated cancer cells creates the opportunity for a new targeted therapy modality: exosome-directed catalyst prodrug therapy, whose first steps are presented herein with the cell-specific release of the anticancer drug panobinostat.
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http://dx.doi.org/10.1038/s41929-019-0333-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6795537PMC
October 2019

Gas phase detection of chemical warfare agents CWAs with portable Raman.

J Hazard Mater 2020 02 23;384:121279. Epub 2019 Sep 23.

Nanoscience Institute of Aragon (INA), University of Zaragoza, Department of Chemical & Environmental Engineering, Edificio I+D+i, Campus Rio Ebro, C/Mariano Esquillor s/n, 50018, Zaragoza, Spain; Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain. Electronic address:

The development of SERS substrates for chemical detection of specific analytes requires appropriate selection of plasmonic metal and the surface where it is deposited. Here we deposited Ag nanoplates on three substrates: i) conventional SiO/Si wafer, ii) stainless steel mesh and iii) graphite foils. The SERS enhancement of the signal was studied for Rhodamine 6 G (R6 G) as common liquid phase probe molecule. We conducted a comprehensive study with λ = 532, 633 and 785 nm on all the substrates. The best substrate was investigated, at the optimum laser 785 nm, for gas phase detection of dimethyl methyl phosphonate (DMMP), simulant of the G-series nerve agents, at a concentration of 2.5 ppmV (14 mg/m). The spectral fingerprint was clearly observed; with variations on the relative intensities of SERS Raman bands compared to bulk DMMP in liquid phase reflects the DMMP-Ag interactions. These interactions were simulated by Density Functional Theory (DFT) calculations and the simulated spectra matched with the experimental one. Finally, we were detected the characteristics DMMP fingerprint with hand-held portable equipment. These results open the way for the application of SERS technique on real scenarios where robust, light-weight, miniaturized and simple to use and cost-effective tools are required by first responders.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121279DOI Listing
February 2020

Efficient encapsulation of theranostic nanoparticles in cell-derived exosomes: leveraging the exosomal biogenesis pathway to obtain hollow gold nanoparticle-hybrids.

Nanoscale 2019 Oct 9;11(40):18825-18836. Epub 2019 Oct 9.

Networking Research Center of Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029-Madrid, Spain and Instituto Aragonés de Ciencias de la Salud (IACS), Centro de Investigación Biomédica de Aragón (CIBA), 50009-Zaragoza, Spain and IIS Aragón(IISA), Centro de Investigación Biomédica de Aragón (CIBA), 50009-Zaragoza, Spain and Fundación ARAID. Avda. Ranillas, 1-D, planta 2ª, oficina b, 50018-Zaragoza, Spain.

Exosomes can be considered natural targeted delivery systems able to carry exogenous payloads, drugs or theranostic nanoparticles (NPs). This work aims to combine the therapeutic capabilities of hollow gold nanoparticles (HGNs) with the unique tumor targeting properties provided by exosomes. Here, we tested different methods to encapsulate HGNs (capable of absorbing light in the NIR region for selective thermal ablation) into murine melanoma cells derived exosomes (B16-F10-exos), including electroporation, passive loading by diffusion, thermal shock, sonication and saponin-assisted loading. These methods gave less than satisfactory results: although internalization of relatively large NPs into B16-F10-exos was achieved by almost all the physicochemical methods tested, only about 15% of the exosomes were loaded with NPs and several of those processes had a negative effect regarding the morphology and integrity of the loaded exosomes. In a different approach, B16-F10 cells were pre-incubated with PEGylated HGNs (PEG-HGNs) in an attempt to incorporate the NPs into the exosomal biogenesis pathway. The results were highly successful: exosomes recovered from the supernatant of the cell culture showed up to 50% of HGNs internalization. The obtained hybrid HGN-exosome vectors were characterized with a battery of techniques to make sure that internalization of HGNs did not affect exosome characteristics compared with other strategies. PEG-HGNs were released through the endosomal-exosome biogenesis pathway confirming that the isolated vesicles were exosomes.
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http://dx.doi.org/10.1039/c9nr06183eDOI Listing
October 2019

Gold nanoparticles for the in situ polymerization of near-infrared responsive hydrogels based on fibrin.

Acta Biomater 2019 12 27;100:306-315. Epub 2019 Sep 27.

Hospital Universitario La Paz-IdiPAZ, Paseo de la Castellana 261, Madrid 28046 Spain; CIBER de Bioingenieria, Biomateriales y Nanomedicina, CIBER-BBN, Spain. Electronic address:

Non-invasiveness and relative safety of photothermal therapy, which enables local hyperthermia of target tissues using a near infrared (NIR) laser, has attracted increasing interest. Due to their biocompatibility, amenability of synthesis and functionalization, gold nanoparticles have been investigated as therapeutic photothermal agents. In this work, hollow gold nanoparticles (HGNP) were coated with poly-l-lysine through the use of COOH-Poly(ethylene glycol)-SH as a covalent linker. The functionalized HGNP, which peak their surface plasmon resonance at 800 nm, can bind thrombin. Thrombin-conjugated HGNP conduct in situ fibrin polymerization, facilitating the process of generating photothermal matrices. Interestingly, the metallic core of thrombin-loaded HGNP fragmentates at physiological temperature. During polymerization process, matrices prepared with thrombin-loaded HGNP were loaded with genetically-modified stem cells that harbour a heat-activated and ligand-dependent gene switch for regulating transgene expression. NIR laser irradiation of resulting cell constructs in the presence of ligand successfully triggered transgene expression in vitro and in vivo. STATEMENT OF SIGNIFICANCE: Current technological development allows synthesis of gold nanoparticles (GNP) in a wide range of shapes and sizes, consistently and at scale. GNP, stable and easily functionalized, show low cytotoxicity and high biocompatibility. Allied to that, GNP present optoelectronic properties that have been exploited in a range of biomedical applications. Following a layer-by-layer functionalization approach, we prepared hollow GNP coated with a positively charged copolymer that enabled thrombin conjugation. The resulting nanomaterial efficiently catalyzed the formation of fibrin hydrogels which convert energy of the near infrared (NIR) into heat. The resulting NIR-responsive hydrogels can function as scaffolding for cells capable of controlled gene expression triggered by optical hyperthermia, thus allowing the deployment of therapeutic gene products in desired spatiotemporal frameworks.
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http://dx.doi.org/10.1016/j.actbio.2019.09.040DOI Listing
December 2019

Differences in levan nanoparticles depending on their synthesis route: Microbial vs cell-free systems.

Int J Biol Macromol 2019 Sep 27;137:62-68. Epub 2019 Jun 27.

Department of Chemical Engineering, University of Salamanca, Plaza Los Caídos s/n, Salamanca, Spain; Institute for Biomedical Research of Salamanca (IBSAL), Paseo de San Vicente, 58-182, Salamanca, Spain. Electronic address:

Differences between the levan obtained from bacteria and from cell-free systems were studied in this work. Results showed that both polymers are non-porous solids (type II isotherm with 20 m/g) with a main thermal decomposition at 200 °C and a negligible value of protein adsorption. Microbial levan produced nanoparticles of 90 nm in diameter whereas nanoparticles of 110 nm were obtained with the polymer obtained from a cell-free system. Both polymers behave as aggregates depending on the critical aggregation concentration. At the same time, that concentration depends on the technique used for the polymer synthesis. Cell-free system aggregation concentration is 0.24 mg/mL whereas a concentration of 0.05 mg/mL was found for the microbial system. In both cases, the average molecular weight of the aggregate is higher than 2000 kDa. These results highlight the existence of aggregation equilibrium for both polymers that has to be taken into account for future applications.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.06.128DOI Listing
September 2019

Upconverting Carbon Nanodots from Ethylenediaminetetraacetic Acid (EDTA) as Near-Infrared Activated Phototheranostic Agents.

Chemistry 2019 Apr 20;25(21):5539-5546. Epub 2019 Mar 20.

Department of Chemical and Environmental Engineering and Institute of Nanoscience of Aragon (INA), University of Zaragoza, Campus Rio Ebro, R+D Building, C/Mariano Esquillor s/n, 50018, Zaragoza, Spain.

This work describes the synthesis of nitrogen-doped carbon nanodots (CNDs) synthesized from ethylenediaminetetraacetic acid (EDTA) as a precursor and their application as luminescent agents with a dual-mode theranostic role as near-infrared (NIR) triggered imaging and photodynamic therapy agents. Interestingly, these fluorescent CNDs are more rapidly and selectively internalized by tumor cells and exhibit very limited cytotoxicity until remotely activated with a NIR illumination source. These CNDs are excellent candidates for phototheranostic purposes, for example, simultaneous imaging and therapy can be carried out on cancer cells by using their luminescent properties and the in situ generation of reactive oxidative species (ROS) upon excitation in the NIR range. In the presence of CNDs, NIR remote activation induces the in vitro killing of U251MG cells. Through the use of flow imaging cytometry, we have been able to successfully map and quantify the different types of cell deaths induced by the presence of intracellular superoxide anions ( O ) and hydrogen peroxide (H O ) ROS generated in situ upon NIR irradiation.
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http://dx.doi.org/10.1002/chem.201806307DOI Listing
April 2019

Exosome origin determines cell targeting and the transfer of therapeutic nanoparticles towards target cells.

J Nanobiotechnology 2019 Jan 25;17(1):16. Epub 2019 Jan 25.

Department of Chemical Engineering, Aragon Institute of Nanoscience (INA), University of Zaragoza, Campus Río Ebro-Edificio I+D, C/ Mariano Esquillor S/N, 50018, Zaragoza, Spain.

Background: Exosomes are considered key elements for communication between cells, but very little is known about the mechanisms and selectivity of the transference processes involving exosomes released from different cells.

Results: In this study we have investigated the transfer of hollow gold nanoparticles (HGNs) between different cells when these HGNs were loaded within exosomes secreted by human placental mesenchymal stem cells (MSCs). These HGNs were successfully incorporated in the MSCs exosome biogenesis pathway and released as HGNs-loaded exosomes. Time-lapse microscopy and atomic emission spectroscopy allowed us to demonstrate the selective transfer of the secreted exosomes only to the cell type of origin when studying different cell types including cancer, metastatic, stem or immunological cells.

Conclusions: In this study we demonstrate the selectivity of in vitro exosomal transfer between certain cell types and how this phenomenon can be exploited to develop new specific vectors for advanced therapies. Specifically, we show how this preferential uptake can be leveraged to selectively induce cell death by light-induced hyperthermia only in cells of the same type as those producing the corresponding loaded exosomes. We describe how the exosomes are preferentially transferred to some cell types but not to others, thus providing a better understanding to design selective therapies for different diseases.
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http://dx.doi.org/10.1186/s12951-018-0437-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6346572PMC
January 2019

Modelling spatial patterns of correlations between concentrations of heavy metals in mosses and atmospheric deposition in 2010 across Europe.

Environ Sci Eur 2018 21;30(1):53. Epub 2018 Dec 21.

29University of Vienna, Vienna, Austria.

Background: This paper aims to investigate the correlations between the concentrations of nine heavy metals in moss and atmospheric deposition within ecological land classes covering Europe. Additionally, it is examined to what extent the statistical relations are affected by the land use around the moss sampling sites. Based on moss data collected in 2010/2011 throughout Europe and data on total atmospheric deposition modelled by two chemical transport models (EMEP MSC-E, LOTOS-EUROS), correlation coefficients between concentrations of heavy metals in moss and in modelled atmospheric deposition were specified for spatial subsamples defined by ecological land classes of Europe (ELCE) as a spatial reference system. Linear discriminant analysis (LDA) and logistic regression (LR) were then used to separate moss sampling sites regarding their contribution to the strength of correlation considering the areal percentage of urban, agricultural and forestry land use around the sampling location. After verification LDA models by LR, LDA models were used to transform spatial information on the land use to maps of potential correlation levels, applicable for future network planning in the European Moss Survey.

Results: Correlations between concentrations of heavy metals in moss and in modelled atmospheric deposition were found to be specific for elements and ELCE units. Land use around the sampling sites mainly influences the correlation level. Small radiuses around the sampling sites examined (5 km) are more relevant for Cd, Cu, Ni, and Zn, while the areal percentage of urban and agricultural land use within large radiuses (75-100 km) is more relevant for As, Cr, Hg, Pb, and V. Most valid LDA models pattern with error rates of < 40% were found for As, Cr, Cu, Hg, Pb, and V. Land use-dependent predictions of spatial patterns split up Europe into investigation areas revealing potentially high (= above-average) or low (= below-average) correlation coefficients.

Conclusions: LDA is an eligible method identifying and ranking boundary conditions of correlations between atmospheric deposition and respective concentrations of heavy metals in moss and related mapping considering the influence of the land use around moss sampling sites.
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http://dx.doi.org/10.1186/s12302-018-0183-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6302881PMC
December 2018

Luminescent mesoporous nanorods as photocatalytic enzyme-like peroxidase surrogates.

Chem Sci 2018 Oct 24;9(40):7766-7778. Epub 2018 Aug 24.

Institute of Nanoscience of Aragon (INA) , Department of Chemical Engineering and Environmental Technology , University of Zaragoza , 50018 Zaragoza , Spain . Email: ; Email:

Herein we report on a novel inorganic peroxidase-mimicking nanocatalyst activated under blue LED photoirradiation. A novel flash-pyrolysis method has been developed for the generation of strong blue photoluminescence (PL) centers attributed to silicon and carbon-based sites within a mesoporous SBA-15 silica nanorod platform. The type of centers and their PL response can be controlled by varying the flash thermal treatment conditions. By tailoring the operating conditions the system can be driven towards the preferential generation of carbon-based luminescent centers, with or without the simultaneous generation of silicon-based centers. The properties and the nature of these luminescent centers within the mesoporous nanorods have been thoroughly corroborated by a battery of characterization techniques including fluorescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and electron energy loss spectroscopy (EELS) at the local level of the structures combined with scanning transmission electron microscopy (STEM) imaging. In addition, these luminescent mesoporous nanorods have been successfully tested as robust photocatalysts able to display peroxidase-like activity and indirect glucose sensing in a wider range of pH conditions compared to the natural enzyme, especially when carbogenic dots and oxygen-deficient silica centers are simultaneously present in the structure.
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http://dx.doi.org/10.1039/c8sc03112fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6194581PMC
October 2018

Laser-Assisted Production of Carbon-Encapsulated Pt-Co Alloy Nanoparticles for Preferential Oxidation of Carbon Monoxide.

Front Chem 2018 16;6:487. Epub 2018 Oct 16.

Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Zaragoza, Spain.

C-encapsulated highly pure PtCo alloy nanoparticles have been synthesized by an innovative one-step laser pyrolysis. The obtained X-ray diffraction pattern and transmission electron microscopy images correspond to PtCo alloy nanoparticles with average diameters of 2.4 nm and well-established crystalline structure. The synthesized PtCo/C catalyst containing 1.5 wt% of PtCo nanoparticles can achieve complete CO conversion in the temperature range 125-175°C working at weight hourly space velocities (WHSV) of 30 L hg. This study shows the first example of bimetallic nanoalloys synthesized by laser pyrolysis and paves the way for a wide variety of potential applications and metal combinations.
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http://dx.doi.org/10.3389/fchem.2018.00487DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6198107PMC
October 2018

Fast and simple assessment of surface contamination in operations involving nanomaterials.

J Hazard Mater 2019 02 4;363:358-365. Epub 2018 Oct 4.

Instituto de Nanociencia de Aragón (INA) - Universidad de Zaragoza, c/Mariano Esquillor s/n, 50018, Zaragoza, Spain; Networking Biomedical Research Centre for Biomaterials, Bioengineering and Nanomedicine (CIBER-BBN), c/Monforte de Lemos 28, 28040, Madrid, Spain. Electronic address:

The deposition of airborne nanosized matter onto surfaces could pose a potential risk in occupational and environmental scenarios. The incorporation of fluorescent labels, namely fluorescein isotiocyanate (FITC) or tris-1,3-phenanthroline ruthenium (II) chloride (Ru(phen)Cl), into spherical 80-nm silica nanoparticles allowed the detection after the illumination with LED light of suitable wavelength (365 or 405 nm respectively). Monodisperse nanoparticle aerosols from fluorescently labeled nanoparticles were produced under safe conditions using powder generators and the deposition was tested into different surfaces and filtering media. The contamination of gloves and work surfaces that was demonstrated by sampling and SEM analysis becomes immediately clear under laser or LED illumination. Furthermore, nanoparticle aerosols of about 10 nanoparticles/cm were alternatively fed through a glass pipe and personal protective masks to identify the presence of trapped nanoparticles under 405 nm or 365 nm LED light. This testing procedure allowed a fast and reliable estimation of the contamination of surfaces with nanosized matter, with a limit of detection based on the fluorescence emission of the accumulated solid nanoparticles of 40 ng of Ru(phen)@SiO of silica per mg of non-fluorescent matter.
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http://dx.doi.org/10.1016/j.jhazmat.2018.10.011DOI Listing
February 2019

CFD modelling of air quality in Pamplona City (Spain): Assessment, stations spatial representativeness and health impacts valuation.

Sci Total Environ 2019 Feb 25;649:1362-1380. Epub 2018 Aug 25.

Chemistry Department, University of Navarra, Spain.

A methodology based on CFD-RANS simulations (WA CFD-RANS, Weighted Averaged Computational Fluid Dynamic-Reynolds-Averaged Navier-Stokes simulations) which includes appropriate modifications, has been applied to compute the annual, seasonal, and hourly average concentration of NO and NO throughout the city of Pamplona (Spain) at pedestrian level during 2016. The results have been evaluated using measurements provided both by the city's network of air quality monitoring stations and by a network of mobile microsensors carried around by cyclists during their daily commutes, obtaining a maximum relative error lower than 30% when computing NO annual average concentrations. The model has taken into account the actual city layout in three dimensions, as well as the traffic emissions. The resulting air pollution maps provided information critical for studying the traffic-related health effects of NO and their associated external costs in the city of Pamplona and the spatial representativeness of the current network of air quality monitoring stations (it has not been carried out for an entire city to date). The developed methodology can be applied to similar cities, providing useful information for the decision-makers.
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http://dx.doi.org/10.1016/j.scitotenv.2018.08.315DOI Listing
February 2019

Multi-element isotopic signature (C, N, Pb, Hg) in epiphytic lichens to discriminate atmospheric contamination as a function of land-use characteristics (Pyrénées-Atlantiques, SW France).

Environ Pollut 2018 Dec 17;243(Pt B):961-971. Epub 2018 Sep 17.

CNRS, Univ Pau & Pays Adour, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Materiaux, UMR5254, 64000, PAU, France.

Multi-elemental isotopic approach associated with a land-use characteristic sampling strategy may be relevant for conducting biomonitoring studies to determine the spatial extent of atmospheric contamination sources. In this work, we investigated how the combined isotopic signatures in epiphytic lichens of two major metallic pollutants, lead (Pb/Pb) and mercury (δHg, ΔHg), together with the isotopic composition of nitrogen and carbon (δN, δC), can be used to better constrain atmospheric contamination inputs. To this end, an intensive and integrated sampling strategy based on land-use characteristics (Geographic information system, GIS) over a meso-scale area (Pyrénées-Atlantiques, SW France) was applied to more than 90 sampling stations. To depict potential relationships between such multi-elemental isotopic fingerprint and land-use characteristics, multivariate analysis was carried out. Combined Pb and Hg isotopic signatures resolved spatially the contribution of background atmospheric inputs from long range transport, from local legacy contamination (i.e. Pb) or actual industrial inputs (i.e. Pb and Hg from steel industry). Application of clustering multivariate analysis to all studied isotopes provided a new assessment of the region in accordance with the land-use characteristics and anthropogenic pressures.
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http://dx.doi.org/10.1016/j.envpol.2018.09.003DOI Listing
December 2018

Joining empirical and modelling approaches to estimate dry deposition of nitrogen in Mediterranean forests.

Environ Pollut 2018 Dec 5;243(Pt A):427-436. Epub 2018 Sep 5.

Ecotoxicology of Air Pollution, CIEMAT, Av. Complutense 40, Ed.70, 28040, Madrid, Spain.

In Mediterranean areas, dry deposition is a major component of the total atmospheric N input to natural habitats, particularly to forest ecosystems. An innovative approach, combining the empirical inferential method (EIM) for surface deposition of NO and NH with stomatal uptake of NH, HNO and NO derived from the DOSE (Deposition of Ozone and Stomatal Exchange) model, was used to estimate total dry deposition of inorganic N air pollutants in four holm oak forests under Mediterranean conditions in Spain. The estimated total deposition varied among the sites and matched the geographical patterns previously found in model estimates: higher deposition was determined at the northern site (28.9 kg N ha year) and at the northeastern sites (17.8 and 12.5 kg N ha year) than at the central-Spain site (9.4 kg N ha year). On average, the estimated dry deposition of atmospheric N represented 77% ± 2% of the total deposition of N, of which surface deposition of gaseous and particulate atmospheric N averaged 10.0 ± 2.9 kg N ha year for the four sites (58% of the total deposition), and stomatal deposition of N gases averaged 3.3 ± 0.8 kg N ha year (19% of the total deposition). Deposition of atmospheric inorganic N was dominated by the surface deposition of oxidized N in all the forests (means of 54% and 42% of the dry and total deposition, respectively). The relative contribution of NO to dry deposition averaged from 19% in the peri-urban forests to 11% in the most natural site. During the monitoring period, the empirical critical loads provisionally proposed for ecosystem protection (10-20 kg N ha year) was exceeded in three of the four studied forests.
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http://dx.doi.org/10.1016/j.envpol.2018.09.015DOI Listing
December 2018

Pro-angiogenic near infrared-responsive hydrogels for deliberate transgene expression.

Acta Biomater 2018 09 9;78:123-136. Epub 2018 Aug 9.

University Hospital La Paz-IdiPAZ, Paseo de la Castellana 261, Madrid 28046, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina, CIBER-BBN, Spain. Electronic address:

CuS nanoparticles (CuSNP) are degradable, readily prepared, inexpensive to produce and efficiently cleared from the body. In this work, we explored the feasibility of CuSNP to function as degradable near infrared (NIR) nanotransducers within fibrin-based cellular scaffolds. To prepare NIR-responsive CuSNP hydrogels, fibrinogen was dissolved in cell culture medium and supplemented with aqueous dispersions of CuSNP. Fibrinogen polymerization was catalyzed by the addition of thrombin. In some experiments, HUVEC, C3H/10T1/2 or C3H/10T1/2-fLuc cells, that harbor a heat-activated and rapamycin-dependent gene switch for regulating the expression of firefly luciferase transgene, were incorporated to the sol phase of the hydrogel. For in vivo experiments, hydrogels were injected subcutaneously in the back of adult C3H/HeN mice. Upon NIR irradiation, CuSNP hydrogels allowed heat-inducible and rapamycin-dependent transgene expression in cells contained therein, in vitro and in vivo. C3H/10T1/2 cells cultured in CuSNP hydrogels increased metabolic activity, survival rate and fibrinolytic activity, which correlated with changes at the transcriptome level. Media conditioned by CuSNP hydrogels increased viability of HUVEC which formed pseudocapillary structures and remodeled protein matrix when entrapped within these hydrogels. After long-term implantation, the skin patches that covered the CuSNP hydrogels showed increased capillary density which was not detected in mice implanted with matrices lacking CuSNP. In summary, NIR-responsive scaffolds harboring CuSNP offer compelling features in the tissue engineering field, as degradable implants with enhanced integration capacity in host tissues that can provide remote controlled deployment of therapeutic gene products.

Statement Of Significance: Hydrogels composed of fibrin embedding copper sulfide nanoparticles (CuSNP) efficiently convert incident near infrared (NIR) energy into heat and can function as cellular scaffolding. NIR laser irradiation of CuSNP hydrogels can be employed to remotely induce spatiotemporal patterns of transgene expression in genetically engineered multipotent stem cells. CuSNP incorporation in hydrogel architecture accelerates the cell-mediated degradation of the fibrin matrix and induces pro-angiogenic responses that may facilitate the integration of these NIR-responsive scaffolds in host tissues. CuSNP hydrogels that harbor cells capable of controlled expression of therapeutic gene products may be well suited for tissue engineering as they are biodegradable, enhance implant vascularization and can be used to deploy growth factors in a desired spatiotemporal fashion.
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http://dx.doi.org/10.1016/j.actbio.2018.08.006DOI Listing
September 2018

Carbon and nitrogen isotopes unravels sources of aerosol contamination at Caribbean rural and urban coastal sites.

Sci Total Environ 2018 Nov 15;642:723-732. Epub 2018 Jun 15.

Geotop/Université du Québec à Montréal (UQAM), 201 Ave Président Kennedy, Montréal, QC, Canada.

The constant increase of anthropogenic emissions of aerosols, usually resulting from a complex mixture from various sources, leads to a deterioration of the ambient air quality. The stable isotope compositions (δC and δN) of total carbon (TC) and nitrogen (TN) in both PM and emissions from potential sources were investigated for first time in a rural and an urban Caribbean costal sites in Cuba to better constrain the origin of the contamination. Emissions from road traffic, power plant and shipping emissions were discriminated by coupling their C and N contents and corresponding isotope signatures. Other sources (soil, road dust and cement plant), in contrast, presented large overlapping ranges for both C and N isotope compositions. δC isotope compositions in the rural (average of -25.4 ± 1.2‰) and urban (average of -24.8 ± 1.2‰) sites were interpreted as a mixture of contributions from two main contributors: i) fossil fuel combustion and ii) cement plant and quarries. Results also showed that this last source is impacting more air quality at the urban site. A strong influence from local wood burning was also identified at the rural site. These conclusions were comforted by a statistical analysis using a conditional bivariate probability function. TN and δN values from the urban site demonstrated that nitrogen in PM was generated by secondary processes through the formation of (NH)SO. The exchange in the (NH)SO molecule between gaseous NH and particle NH under stoichiometric equilibrium may control the observed N enrichment. At low nitrogen concentrations in the aerosols, representing PM with both the highest primary N and lowest secondary N proportions, comparison with the δN of potential sources indicate that emissions from diesel car and power plant emissions may represent the major vectors of primary nitrogen.
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http://dx.doi.org/10.1016/j.scitotenv.2018.06.106DOI Listing
November 2018

Microwave-Assisted Catalytic Combustion for the Efficient Continuous Cleaning of VOC-Containing Air Streams.

Environ Sci Technol 2018 05 25;52(10):5892-5901. Epub 2018 Apr 25.

Nanoscience Institute of Aragon and Chemical and Environmental Engineering Department , University of Zaragoza , 50018 Zaragoza , Spain.

A microwave-heated adsorbent-reactor system has been used for the continuous cleaning of air streams containing n-hexane at low concentrations. Both, a single catalytic bed (PtY zeolite) and a double (adsorptive DAY zeolite + catalytic PtY zeolite) fixed-bed reactor configurations were studied under dry and humid conditions. The zeolites were selectively heated by short periodic microwave pulses that caused the desorption of n-hexane and its subsequent catalytic combustion. The double bed configuration was attractive because it allowed nearly the same performance with only half of the catalyst load. The operation was especially efficient under realistic humid gas conditions that favored more intense microwave absorption, producing a faster heating of the adsorptive and catalytic beds. Under these conditions, continuous gas cleaning could be achieved with short (3 min, 30 W) microwave heating pulses every 5 min.
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http://dx.doi.org/10.1021/acs.est.8b00191DOI Listing
May 2018

A versatile generator of nanoparticle aerosols. A novel tool in environmental and occupational exposure assessment.

Sci Total Environ 2018 Jun 5;625:978-986. Epub 2018 Jan 5.

Instituto de Nanociencia de Aragón (INA), c/Mariano Esquillor s/n, 50018 Zaragoza, Spain; Networking Biomedical Research Centre of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), c/Monforte de Lemos, 28040 Madrid, Spain. Electronic address:

The increasing presence of nanotechnology on the market entails a growing probability of finding ENMs in the environment. Nanoparticles aerosols are a yet unknown risk for human and environmental exposure that may normally occur at any point during the nanomaterial lifecycle. There is a research gap in standardized methods to assess the exposure to airborne nanoparticles in different environments. The controllable generation of nanoparticle aerosols has long been a challenging objective for researchers and industries dealing with airborne nanoparticles. In this work, a versatile system to generate nanoparticulate aerosols has been designed. The system allows the production of both i) instantaneous nanoparticle clouds and ii) continuous nanoparticle streams with quasi-stable values of particle concentration and size distribution. This novel device uses a compressed-air pressure pulse to disperse the target material into either the testing environment (instantaneous cloud formation) or a secondary chamber, from which a continuous aerosol stream can be drawn, with a tunable nanoparticle concentration. The system is robust, highly versatile and easy to operate, enabling reproducible generation of aerosols from a variety of sources. The system has been verified with four dry nanomaterials: TiO, ZnO, CuO and CNT bundles.
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http://dx.doi.org/10.1016/j.scitotenv.2017.12.125DOI Listing
June 2018

Versatile hollow fluorescent metal-silica nanohybrids through a modified microemulsion synthesis route.

J Colloid Interface Sci 2018 Mar 21;513:497-504. Epub 2017 Nov 21.

Instituto de Nanociencia de Aragón (INA), Universidad de Zaragoza, 50018 Zaragoza, Spain; Networking Research Centre for Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28040 Madrid, Spain.

Silica-metal nanohybrids are common materials for applications in biomedicine, catalysis or sensing. Also, hollow structures are of interest as they provide additional useful features. However, in these materials the control of the size and accessibility to the inner regions of the structure usually requires complex synthesis procedures. Here we report a simple colloidal procedure for synthesizing hollow silica-metal nanohybrids, driven by the diffusion of metal precursors through the porous silica shell and subsequent reduction in aqueous solutions. The formation of hollow nanoparticles is controlled by the colloidal conditions during synthesis, which affect the ripening of hollow nanoparticles in presence of organosilanes. The modification of the conditions during synthesis affected the growth of silica precursors in presence of fluorescein isothiocyanate (FITC). The limited access to water molecules during the hydrolysis of silica precursors is attributed to the hydrophobicity of organic fluorescent molecules linked to the condensing silica clusters at the initial stages of nanoparticle formation and to the limitation of water content in the microemulsion method used. Finally, the growth of metal nanoseeds at the core of hollow nanoparticles can be easily achieved though a simple method in aqueous environment. The pH and thermal conditions during the reduction process affect the formation of metal-silica nanohybrids and their structural features.
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http://dx.doi.org/10.1016/j.jcis.2017.11.055DOI Listing
March 2018

Antibiotic-eluting orthopedic device to prevent early implant associated infections: Efficacy, biocompatibility and biodistribution studies in an ovine model.

J Biomed Mater Res B Appl Biomater 2018 07 4;106(5):1976-1986. Epub 2017 Oct 4.

Department of Animal Pathology, University of Zaragoza, Zaragoza, Spain.

Infection of orthopedic devices is a major complication in the postsurgical period generating important health issues and economic consequences. Prevention strategies could be based on local release of antibiotics from the orthopedic device itself to avoid adhesion and growth of bacteria. The purpose of this work is to demonstrate the efficiency to prevent these infections by a cefazolin-eluting, perforated stainless steel implant in an in vivo ovine model. The device was placed in the tibia of sheep, one group receiving cefazolin-loaded implants whereas the control group received empty implants. All implants were experimentally infected by direct inoculation of Staphylococcus aureus ATCC 6538. In vitro cytotoxicological studies were also performed to check the effect of antibiotic on cell viability, integrity, and cycle. Results showed that sheep receiving cefazolin-loaded devices were able to avoid implant-associated infections, with normal tissue healing process. The antibiotic release followed a local concentric pattern as demonstrated by high-performance liquid chromatography detection in tissues. The in vitro results indicate the lack of relevant cytotoxic effects for the maximum antibiotic concentration released by the device. These results demonstrate the efficiency and safety of cefazolin-eluting implants in an ovine model to prevent early postsurgical infections of orthopedic devices. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1976-1986, 2018.
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http://dx.doi.org/10.1002/jbm.b.34009DOI Listing
July 2018

Pumping Metallic Nanoparticles with Spatial Precision within Magnetic Mesoporous Platforms: 3D Characterization and Catalytic Application.

ACS Appl Mater Interfaces 2017 Nov 17;9(47):41529-41536. Epub 2017 Oct 17.

Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN , 28029 Madrid, Spain.

The present work shows an efficient strategy to assemble two types of functional nanoparticles onto mesoporous MCM-41 silica nanospheres with a high degree of spatial precision. In a first stage, magnetite nanoparticles are synthesized with a size larger than the support pores and grafted covalently through a peptide-like bonding onto their external surface. This endowed the silica nanoparticles with a strong superparamagnetic response, while preserving the highly ordered interior space for the encapsulation of other functional guest species. Second, we report the finely controlled pumping of preformed Pt nanoparticles (1.5 nm) within the channels of the magnetic MCM-41 nanospheres to confer an additional catalytic functionality to the multiassembled nanoplatform. The penetration depth of the metallic nanoparticles can be explained as a result of the interplay between the particle-wall electrostatic attraction and the repulsive forces between neighboring Pt nanoparticles. A detailed transmission electron microscopy and a 3D high-resolution high-angle annular dark-field detector electron tomography study were carried out to characterize the material and to explain the assembly mechanism. Finally, the performance of these multifunctional nanohybrids as magnetically recoverable catalysts has been evaluated in the selective hydrogenation of p-nitrophenol, a well-known pollutant and intermediate in multiple industrial processes.
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http://dx.doi.org/10.1021/acsami.7b11482DOI Listing
November 2017

High surface coverage of a self-assembled monolayer by in situ synthesis of palladium nanodeposits.

Nanoscale 2017 Sep;9(35):13281-13290

Instituto de Nanociencia de Aragón (INA), Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquillor, s/n, 50018 Zaragoza, Spain. and Laboratorio de Microscopias Avanzadas (LMA), Campus Río Ebro, Universidad de Zaragoza, C/Mariano Esquilor, s/n, 50018 Zaragoza, Spain and Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain.

Nascent metal|monolayer|metal devices have been fabricated by depositing palladium, produced through a CO-confined growth method, onto a self-assembled monolayer of an amine-terminated oligo(phenylene ethynylene) derivative on a gold bottom electrode. The high surface area coverage (85%) of the organic monolayer by densely packed palladium particles was confirmed by X-ray photoemission spectroscopy (XPS) and atomic force microscopy (AFM). The electrical properties of these nascent Au|monolayer|Pd assemblies were determined from the I-V curves recorded with a conductive-AFM using the Peak Force Tunneling AFM (PF-TUNA™) mode. The I-V curves together with the electrochemical experiments performed rule out the formation of short-circuits due to palladium penetration through the monolayer, suggesting that the palladium deposition strategy is an effective method for the fabrication of molecular junctions without damaging the organic layer.
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http://dx.doi.org/10.1039/c7nr03365fDOI Listing
September 2017

Lipogels responsive to near-infrared light for the triggered release of therapeutic agents.

Acta Biomater 2017 10 8;61:54-65. Epub 2017 Aug 8.

University Hospital La Paz-IdiPAZ, Paseo de la Castellana 261, 28046 Madrid, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina, CIBER-BBN, Spain. Electronic address:

Here we report a composite system based on fibrin hydrogels that incorporate in their structure near-infrared (NIR) responsive nanomaterials and thermosensitive liposomes (TSL). Polymerized fibrin networks entrap simultaneously gold-based nanoparticles (NPs) capable of transducing NIR photon energy into heat, and lysolipid-incorporated TSL (LTSL) loaded with doxorubicin hydrochloride (DOX). NIR irradiation of the resulting hydrogels (referred to as "lipogels") with 808nm laser light increased the temperature of the illuminated areas, leading to the release of the liposomal cargo. Levels of DOX that release from the "smart" composites were dependent on the concentration of NIR nanotransducers loaded in the lipogel, the intensity of the electromagnetic energy deposited and the irradiation regime. Released DOX retained its bioactivity, as shown in cultures of epithelial carcinoma cells. Finally, the developed drug delivery platform was refined by using NIR-photoabsorbers based on copper sulfide NPs to generate completely biodegradable composites as well as through the incorporation of cholesterol (Ch) in LTSL formulation, which lessens leakiness of the liposomal cargo at physiological temperature. This remotely controlled system may suit well for those therapies that require precise control over the dose of delivered drug in a defined spatiotemporal framework.

Statement Of Significance: Hydrogels composed of fibrin embedding nanoparticles responsive to near infrared (NIR) energy and thermosensitive liposomes loaded with doxorubicin hydrochloride (DOX), were prepared by in situ polymerization. NIR-light irradiation of these constructs, referred to as "NIR responsive lipogels", results in the controlled release of DOX to the surrounding medium. This technology may use fully degradable components and can preserve the bioactivity of liposomal cargo after remote triggering to finely regulate the dose and bioavailability of delivered payloads. NIR responsive lipogels technology overcomes the limitations of drug release systems based on the combination of liposomes and degradable polymeric materials, which in many cases lead to insufficient release at therapy onset or to overdose during high degradation period.
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http://dx.doi.org/10.1016/j.actbio.2017.08.010DOI Listing
October 2017