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This work was aimed at characterizing the effects of foliarly applied rutile (TiO2) nanoparticles (NPs) on Ti translocation as well as biomass production and antioxidant system in tomato (Solanum lycopersicum L.). The seeds were germinated and grown on a substrate in individual pots in a growth chamber. The TiO2 NPs were characterized using transmission electron microscopy (TEM), Raman spectroscopy, dynamic light scattering (DLS), and laser doppler velocimetry (LDV). Titanium dioxide NPs had a rod-shaped form and were moderately prone to agglomeration. The TiO2 NPs treatments were applied at 0, 5, 10, 20, 40, 80, and 160 mg L−1 by foliar spraying on 20-day-old S. lycopersicum plants. After 7 days of treatment exposure, tissue Ti concentration was determined by inductively coupled plasma-mass spectrometry (ICP-MS). Nanoparticle treatments increased tissue Ti concentration; Ti was translocated from leaves to stem, triggering a significant decrease in biomass production. With respect to the control, an increase in total reducing capacity (1.7-fold), antioxidant activity (1.5-fold), and superoxide dismutase activity (2-fold) were observed in the treatments with intermediate to high doses. The TiO2 NPs triggered an increase in tissue Ti concentration, increasing the antioxidant system activity and lipid peroxidation at low to intermediate doses, and decreasing biomass production at intermediate to high doses.

In the present work, silver nanoparticles (AgNPs) synthetized with Cryptocarya alba (Peumo) leaf extract were studied. The fabrication method was fast, low cost, and eco-friendly, and the final properties of AgNPs were determined by experimental parameters, such as AgNO3 and Peumo extract concentrations used. Setting suitable experimental conditions, crystalline AgNPs with apparent spherical forms and average diameter around 3.5 nm were obtained. In addition, the capability of synthesized Peumo-AgNPs to remove methylene blue dye (MB) in aqueous solution as well as their catalytic effectiveness was also investigated. The results showed that green synthesized AgNPs can remove fast and effectively the MB dye from aqueous medium by itself, but better results were found acting like catalyst by using sodium borohydride (NaBH4) in the reaction. In addition, this green nanomaterial can be recycling several times maintaining initial properties for removal of MB. Thus, AgNPs synthetized with Peumo leaf extracts could be an excellent catalyst candidate for degradation of blue methylene dye in chemical industries.

“This is the Accepted Manuscript version of an article accepted for publication in Nanotechnology. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.1088/1361-6528/ab96e5”, Composites of nanostructured porous silicon and silver (nPSi-Ag) have attracted great attention due to the wide spectrum of applications in fields such as microelectronics, photonics, photocatalysis and bioengineering, Among the different methods for the fabrication of nanostructured composite materials, dip and spin-coating are simple, versatile, and cost-effective bottom-up technologies to provide functional coatings. In that sense, we aimed at fabricating nPSi-Ag composite layers. Using nPSi layers with pore diameter of 30 nm, two types of thin-film techniques were systematically compared: cyclic dip-coating (CDC) and cyclic spin-coating (CSC). CDC technique formed a mix of granular and flake-like structures of metallic Ag, and CSC method favored the synthesis of flake-like structures with Ag and Ag2O phases. Flakes obtained by CDC and CSC presented a width of 110 nm and 70 nm, respectively. Particles also showed a nanostructure surface with features around 25 nm. According to the results of EDX and RBS, integration of Ag into nPSi was better achieved using the CDC technique. SERS peaks related to chitosan adsorbed on Ag nanostructures were enhanced, especially in the nPSi-Ag composite layers fabricated by CSC compared to CDC, which was confirmed by FTDT simulations. These results show that CDC and CSC produce different nPSi-Ag composite layers for potential applications in bioengineering and photonics, This work was financially supported by Fondo Nacional de Desarrollo Científico y Tecnológico FONDECYT–Chile (grant number 11180395), FONDEQUIP–Chile (project 160152)

In the present work, the fabrication of hybrid porous silicon/green synthetized Ag microparticles was shown and the potential use as carriers for Ag nanoparticles and drug delivery was explored. Hybrid microparticles were fabricated by incorporating green synthetized Ag nanoparticles into porous silicon matrix. The main physicochemical characteristics of the hybrid systems were studied by several techniques including UV-vis spectroscopy, TEM, SEM, XRD and XPS. The toxicology of these hybrid systems was investigated by cell viability, MTT, and comet assays. In addition, the possibility to aggregate different drug to use as drug delivery system was demonstrated by using florfenicol as drug model, due to its importance in salmon industry. The experimental results showed the potential to use these hybrid systems as carries for drug delivery in salmon industry.

The applications of nanoparticles continue to expand into areas as diverse as medicine, bioremediation, cosmetics, pharmacology and various industries, including agri-food production. The widespread use of nanoparticles has generated concerns given the impact these nanoparticles – mostly metal-based such as CuO, Ag, Au, CeO2, TiO2, ZnO, Co, and Pt - could be having on plants. Some of the most studied variables are plant growth, development, production of biomass, and ultimately oxidative stress and photosynthesis. A systematic appraisal of information about the impact of nanoparticles on these processes is needed to enhance our understanding of the effects of metallic nanoparticles and oxides on the structure and function on the plant photosynthetic apparatus. Most nanoparticles studied, especially CuO and Ag, had a detrimental impact on the structure and function of the photosynthetic apparatus. Nanoparticles led to a decrease in concentration of photosynthetic pigments, especially chlorophyll, and disruption of grana and other malformations in chloroplasts. Regarding the functions of the photosynthetic apparatus, nanoparticles were associated with a decrease in the photosynthetic efficiency of photosystem II and decreased net photosynthesis. However, CeO2 and TiO2 nanoparticles may have a positive effect on photosynthetic efficiency, mainly due to an increase in electron flow between the photosystems II and I in the Hill reaction, as well as an increase in Rubisco activity in the Calvin and Benson cycle. Nevertheless, the underlying mechanisms are poorly understood. The future mechanistic work needs to be aimed at characterizing the enhancing effect of nanoparticles on the active generation of ATP and NADPH, carbon fixation and its incorporation into primary molecules such as photo-assimilates.

Over the last few years, the green synthesis of nanoparticles (NPs) using plant extracts has emerged as a promising methodology for the fabrication of metallic NPs (especially silver, copper, and gold NPs), as it involves an easy, fast, low-cost, and environmentally friendly bioprocess. However, many factors affect the sizes and morphologies of NPs biosynthesized by this method, including the nature of the plant extract, among others. Therefore, the green synthesis of metal NPs with defined stability, size, and morphology distribution remains under evaluation. In the present study, we propose aqueous extracts from the endemic-medicinal plant Budleja globosa (“Matico”) as an efficient bioproduct for the green synthesis of silver NPs (AgNPs). Experimental results indicate that room temperature, low concentrations of leaf extracts of B. globosa, and silver nitrate salt were sufficient to biosynthesize AgNPs with uniform size (16 nm) and shape distribution (spherical).

Green synthesis of nanoparticles (NPs) from plant extracts have emerged as a promising methodology for the fabrication of metallic NPs, as it involves an easy, fast, low-cost, and environmentally friendly bioprocess. In the present study, we propose aqueous extracts from the endemic-medicinal plant Peumus boldus (“Boldo”) as an easy, fast, low-cost, and efficient bioproduct for the green synthesis of silver NPs (AgNPs). Our results indicate that room temperature conditions, short reaction time (only 3 h), low concentrations (1%) of leaf extracts of P. boldus, and silver nitrate salts (2 mM) were sufficient to biosynthesize AgNPs in a uniform size (18 nm) and shape distribution (spherical). In addition, stable and pure AgNPs were obtained in this process at the same time.

Oxidized hyaluronic acid cross-linked with adipic acid dihydrazide (oxi-HA/ADH) forms an injectable and biocompatible hydrogel suitable for treatment of musculoskeletal diseases and for drug delivery applications. In that sense, nanoporous silicon (nPSi) can be combined with biopolymers, such as oxi-HA/ADH hydrogel, to display new characteristics, which are not exhibited by the individual constituents alone. Under this context, in this work nPSi microparticles at concentrations from 0.1% to 1% m/v were embedded into oxi-HA/ADH hydrogel to improve its mechanical stability and enhance its control over drug release kinetics using Rose Bengal (RB) as a model drug because its cytotoxic effect in different cancer cell lines and tumors has been previously reported. Our results showed, for both compressive force and stress strength tests, that oxi-HA/ADH hydrogel with 1% nPSi microparticles doubled the values of control samples. Moreover, samples of oxi-HA/ADH with nPSi microparticles improved RB release kinetics control over pure oxi-HA/ADH hydrogel. Finally, the cell viability of nPSi microparticles embedded into oxi-HA/ADH hydrogel was confirmed using fibroblasts, This work was financially supported by FONDECYT–Chile (grant number 11180395), CONICYT PFCHA/DOCTORADO/2017-21172001 (Nelson Naveas) and CNPq 140924/2017-5 (Carla França). We thank Fig. 8. A) Cytotoxicity of nPSi microparticles. B) Cell viability of hydrogels. C.G. Franca ̧ et al. Microporous and Mesoporous Materials 310 (2021) 110634 11 Dr. Héctor Pesenti for providing the DRX facility (FONDEQUIP–Chile, project 160152), and Dr. Luis Sanhueza for optical measurements of UVVis spectroscopy

Titanium dioxide nanoparticles (TiO2NPs) generally have positive effects on growth and physiological parameters in plants, but their impacts on photosynthesis and antioxidant system are poorly understood. This work aimed to assess the effects of TiO2 NPs on photosynthetic performance and antioxidant system in Raphanus sativus L. plants. Treatments consisted of TiO2 NPs and microparticles (μPs) applied foliarly by increasing doses from 10 to 1500 mg L−1, using deionized water as a control. As expected, Ti concentration in leaf tissue increased concomitant with the applied dose, being higher in μPs than NPs. A transient increase in net photosynthetic rate (by about 50 %) and stomatal conductance were observed from 12 to 60 h after the beginning of NPs and μPs treatments compared to the control. These increments were independent of doses and particles size. The photochemical parameters were more influenced by the time than the doses, being electron transport rate (ETR) increased, and non photochemical quenching (NPQ) decreased. The instantaneous water use efficiency (WUEins) was 2-fold higher, and intrinsic water use efficiency (WUEint) was 70 % lower in the treated plants respect to the control. Total phenols concentration increased with increasing doses of NPs and μPs. It is suggested that TiO2 NPs and μPs had a transient positive impact on photosynthesis likely by diffusive effects, increasing the WUEins, and a slight activation of secondary metabolism.

Ordered mesoporous silicas were synthesized via cooperative self-assembly by using rice husk ash as silica source and P123 as main pore structure-directing agent. The incorporation of CTAB and BRIJ C10 as co-surfactant templates by different methods was investigated. Silicas with different pore size and mono-, bi- and trimodal porosity were obtained as a function of the co-surfactant used and the hydrolysis step performed. Low-angle XRD and TEM results confirmed the well-ordered pore structure of the synthesized silicas.

The relative easiness of fabrication of porous silicon, along with the possibility of precisely controlling its many unique properties, has made it a promising material for different applications in a wide variety of fields. In particular, this material is being actively studied for biological and medical applications. Within this context, in this chapter we review the key properties of porous silicon and the most significant applications of porous silicon in the fields of biosensing, bioimaging, drug delivery, and tissue engineering. The different processes commonly used to tailor the behavior of porous silicon for specific applications are also described in detail.

ZnO is probably one of the most studied oxides since ZnO nanostructures are a very rich family of nanomaterials with a broad variety of technological applications. Although several chemical techniques offer the possibility to obtain such ZnO nanostructures, here we show that the controlled modification of the zinc surface by low-energy O bombardment leads to the formation of core-shell Zn/ZnO nano-pyramidal arrays that suppress the reflection of light decreasing the reflectivity below 6% in the wavelength range of 300-900 nm. This controlled and scalable protocol opens the door to a broad range of possibilities for the use of ion bombardment to produce surface modifications for technological applications in the field of photoelectric devices and solar cells., The financial support by the Ministerio de Economía y Competitividad (MINECO) of Spain through the CONSOLIDER-Ingenio 2010 (CSD2008-00023) and MAT2015-69035-REDC programs is gratefully acknowledged.

8 págs.; 8 figs., The fabrication of selectively functionalized micropatterns based on nanostructured porous silicon (nanoPS) by phase mask ultraviolet laser interference is presented here. This single-step process constitutes a flexible method for the fabrication of surface patterns with tailored properties. These surface patterns consist of alternate regions of almost untransformed nanoPS and areas where nanoPS is transformed into Si nanoparticles (Si NPs) as a result of the laser irradiation process. The size of the transformed areas as well as the diameter of the Si NPs can be straightforwardly tailored by controlling the main fabrications parameters including the porosity of the nanoPS layers, the laser interference period areas, and laser fluence. The surface patterns have been found to be appropriate candidates for the development of selectively-functionalized surfaces for biological applications mainly due to the biocompatibility of the untransformed nanoPS regions. © 2016 IOP Publishing Ltd, The authors gratefully acknowledge funding from Ministerio de Economía y Competitividad (Spain) under research projects MAT2013-46572-C2-1-R and MAT2014-54826-C2-1-R. R P acknowledges the grant JCI-2012_13034 from the Juan de la Cierva program.

Probe-based technologies are proliferating as a means of inferring traffic states. Technological companies are interested in traffic data for computing the best routes in a traffic-aware manner and they also provide real-time traffic information with certain temporal accuracy. This paper analyses and evaluates how data provided by a fleet of probe cars can be used to develop a navigation service and how the penetration rate of this service affects a set of city-scale KPIs (Key Performance Indicators) and driver KPIs. The case study adopts a model-driven approach in which microscopic simulation emulates real-size fleets of probe vehicles that provide positions and speed data. What is noteworthy about the modelling behaviour is that drivers are segmented according to their knowledge of network conditions for selected trips: experts, regular drivers, and tourists. The paper presents and discusses the modelling approach and the results obtained from an experimental Barcelona CBD model designed to evaluate the penetration rates of probe vehicles and route guidance. An analysis of the simulation experiments reveals remarkable links among city-scale KPIs, which—from a multivariate point of view—is a novelty. A simulation-based framework for results analysis and visualization is also introduced in order to simplify the simulation results analysis and easily visualize OD paths for driver segments. Throughout this work, the authors have benefited from the support of inLab FIB team at UPC and the suggestions of Jaume Barceló (Emeritus Professor at UPC). This research was funded by Spanish R+D Programs, TRA2016-76914-C3-1-P, and by Secretaria d’Universitats-i-Recerca-Generalitat de Catalunya, 2017-SGR-1749.