Search

Little is known about the production of ruby red copper stained glasses from the Medieval and Renaissance periods apart from the fact that the colour is due to the presence of small metallic copper nanoparticles and that tin, the most common reducing agent used in copper red glass production since the 19th century, is not present. In fact, very few workshops in Europe were able to make red glass in historical times, and they kept it secret, so very little is known about how it was obtained. These workshops exported the red glass throughout Europe. Recently, the presence of copper sulphide particles and the data obtained in the replication red glass following historical recipes suggested that sulphur might be the key ingredient in this process. Here, a collection of historical red glasses from these periods has been analysed using a combination of microanalytical techniques; Electron Microprobe (EM) and Field Emission and Scanning Electron Microscopy (FESEM) to verify the chemical composition and nanostructure of the glasses, Synchrotron radiation micro-X-Ray Diffraction (micro-XRD) to establish the nature of the nanocrystalline precipitates, and S, Cu and Fe K-edge micro-X-Ray Absorption Spectroscopy (micro-XAS) to determine the speciation. The data obtained show that the oxidation of S2- into S6+ in the glass is responsible for the precipitation of copper nanoparticles. The development of a sulphide-silicate partition and the presence of Fe3+ in the melt give rise to the precipitation of the high-pressure tetragonal polymorph of chalcocite (Cu2S). Differences between the Medieval and Renaissance red glass are determined.

Cellulose-based composites have aroused increasing interest as potential replacements for fossil fuel-based plastics. In this work, transparent cellulose-grafted-PLA nanocomposite films were prepared by grafting polylactide (PLA) onto cellulose. PLA was synthesized by in situ ring opening polymerization from a regenerated cellulose matrix, using zinc oxide nanoparticles (ZnONPs) in 1-ethyl-3-methylimidazolium acetate (EmimAc) as solvent. A facile route was devised to modify the starting material (cellulose paper) by partial dissolution and regeneration that used an ionic liquid (IL) as a smart nanowelding agent to assemble nanometric cellulose structures. The influence of the proportion of ZnONPs (1–5 wt%) and $$\textit{L}$$ L -lactide (LA) monomers (10–70 wt%) used on the properties of the resulting nanocomposite films was examined by comparison with an all-cellulose composite (ACC) and pure cellulose paper. Incorporating ZnONPs and PLA was found to enhance the mechanical, barrier and optical properties of the films. The maximum tensile strength and best barrier properties were those of a film obtained from 5%ZnONPs and 70%LA. FTIR spectra confirmed a new form of interaction between PLA and the regenerated cellulose matrix. Also, XRD spectra revealed a transition from cellulose I to II and an increase in the proportion of noncrystalline cellulose through partial dissolution and regeneration. Although the surface morphology of the nanocomposite films was influenced by the presence of ZnONPs and PLA chains, their color and chemical structure were not. The transparent cellulose-grafted-PLA nanocomposite films obtained are highly promising as packaging materials.

Drought stress can be described as multidimensional stress factors affecting plants’ growth, development, and productivity. In order to reduce the adverse impact of drought stress, a plethora of attempts have been employed. Among those attempts, nano-engineered particles have gained a remarkable attention. Of the relevant particles, calcium oxide (CaO) and graphene oxide (GO) have been well-documented to positively regulate and mediate the plant growth system through shifting physiological biochemical and molecular aspects of the plant. The solo impacts of the nanoparticles are well-known but their interactions were not assayed for Medicago sativa L. cultivars. For that reason, the present study investigates the impact of CaO NPs and GO on the response and regulation of the defensive mechanism in alfalfa (Medicago sativa L.) callus in drought stress-suffered cultivars. The activation of CaO-GO can be induced with mannitol in the callus of alfalfa cultivars. Dry and fresh weight values were determined in callus samples. There were significant differences between cultivars and concentration. In terms of MDA, H2O2, proline content, it was observed that the Ca2+ NPs application was important, and it showed a strong link with the resistance degree of cultivars. Erzurum cultivar was observed for better proline content with 1.5 ppm GO. MDA activities demonstrated an increasing trend concerning concentrations of mannitol and nanoparticles. The MDA highest activity was observed with 1/2 ppm CaO+0.5/1.5 ppm GO (0.1849 mg/g FW) in the Erzurum. However, the Erzurum cultivar responded with better H2O2 content with 100 mM mannitol +0.5 ppm (0.1017 mg/g FW). This result has presented, under in vitro conditions, that the supplementation of CaO and GO can importantly reduce the negative impacts of drought stress on alfalfa callus; additionally, it has been seen that the dosages of nanoparticle and mannitol are also important.

Antibody-functionalized nanoparticles (NPs) have shown numerous benefits in drug delivery and biosensing, improving the specificity of cell targeting and analyte detection, respectively. However, one of the main challenges is the lack of control over antibody orientation on the NP surface. Popular and easy conjugation strategies, such as carbodiimide-based conjugations, lead to a random orientation of antibodies on the NPs, compromising ligand functionality and contributing to undesired biological effects and reduced target recognition. While new methods for more controlled NP functionalization have been proposed, there is a lack of techniques that can elucidate the orientation of the antibodies at the single-particle level to determine the conjugation outcome and, therefore, the NPs' potential in selective targeting. Here, spectrally-resolved direct stochastic optical reconstruction microscopy (SR-dSTORM), an optical super-resolution technique, is introduced to quantify the relationship between total and functional NP conjugated cetuximab antibodies at the single-particle level. An evident single-particle heterogeneity in total and functional cetuximab is observed, leading to particles with different functional : total ratios. Additionally, the results indicate that the functional : total ratio of cetuximab highly depends on the conjugated cetuximab concentration. Overall, SR-dSTORM represents a direct approach for the NP structure-functionality relationship quantification, providing a platform to improve antibody-conjugated NPs characterization and facilitating their rational design.

In viscous fluids, motile microentities such as bacteria or artificial swimmers often display different transport modes than macroscopic ones. A current challenge in the field aims at using friction asymmetry to steer the motion of microscopic particles. Here we show that lithographically shaped magnetic microtriangles undergo a series of complex transport modes when driven by a precessing magnetic field, including a surfing-like drift close to the bottom plane. In this regime, we exploit the triangle asymmetric shape to obtain a transversal drift which is later used to transport the microtriangle in any direction along the plane. We explain this friction-induced anisotropic sliding with a minimal numerical model capable to reproduce the experimental results. Due to the flexibility offered by soft-lithographic sculpturing, our method to guide anisotropic-shaped magnetic microcomposites can be potentially extended to many other field responsive structures operating in fluid media.

This research explores the impact of Cu composition, heating temperature, and milling time on the production of copper-tin alloy nanoparticles. By employing design of experiments techniques, the study systematically evaluates these input variables and their effects on particle size, optical density, and number of colonies. The identification of new Cu3Sn phases in the nanoparticle structure contributes to the novelty of this research. The findings highlight the potential for optimizing copper-tin alloy nanoparticle synthesis and enhancing their antibacterial properties. Mechanical alloying is found to produce nanoparticles up to 15 nm in size. Increasing the percentage of copper leads to improved antibacterial properties. This work provides insights into the synthesis process of copper-tin mechanical alloying and their potential for antibacterial applications.

8 pags., 5 figs., 1 tab. -- This article is part of the themed collection: Festschrift Wolfgang E. Ernst: Electronic & Nuclear Dynamics in Molecules, Clusters, and on Surfaces .-- Supplementary movie: https://www.rsc.org/suppdata/d3/cp/d3cp01303k/d3cp01303k1.mp4, Experimental and theoretical work has delivered evidence of the helium nanodroplet-mediated synthesis and soft-landing of metal nanoparticles, nanowires, clusters, and single atoms on solid supports. Recent experimental advances have allowed the formation of charged metal clusters into multiply charged helium nanodroplets. The impact of the charge of immersed metal species in helium nanodroplet-mediated surface deposition is proved by considering silver atoms and cations at zero-temperature graphene as the support. By combining high-level ab initio intermolecular interaction theory with a full quantum description of the superfluid helium nanodroplet motion, evidence is presented that the fundamental mechanism of soft-deposition is preserved in spite of the much stronger interaction of charged species with surfaces, with high-density fluctuations in the helium droplet playing an essential role in braking them. Corroboration is also presented that the soft-landing becomes favored as the helium nanodroplet size increases., This work has been partly supported by the Spanish Agencia Estatal de Investigación (AEI) under grant no. PID2020-117605GB-I00/AEI/10.13039/501100011033. This publication is also based upon work of COST Action CA21101 “Confined molecular systems: from a new generation of materials to the stars” (COSY) supported by COST (European Cooperation in Science and Technology). We are also greatly thankful for the support of the EU Doctoral Network PHYMOL 101073474 (project call reference HORIZON-MSCA-2021-DN-01). B. F. acknowledges Xunta de Galicia (grant number ED431C 2021/40) for further financial support. M. Pi acknowledges the Ministerio de Ciencia e Innovación Grant No. PID2020-114626GB-I00 from the MICIN/AEI/10.13039/501100011033. The CESGA supercomputer center (Spain) is acknowledged for having provided the computational resources. We also acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

Antibacterial activity; Biofilms; Silver nanoparticles Actividad antibacteriana; Biopelículas; Nanopartículas de plata Activitat antibacteriana; Biopel·lícules; Nanopartícules de plata In view of the current increase and spread of antimicrobial resistance (AMR), there is an urgent need to find new strategies to combat it. This study had two aims. First, we synthesized highly monodispersed silver nanoparticles (AgNPs) of approximately 17 nm, and we functionalized them with mercaptopoly(ethylene glycol) carboxylic acid (mPEG-COOH) and amikacin (AK). Second, we evaluated the antibacterial activity of this treatment (AgNPs_mPEG_AK) alone and in combination with hyperthermia against planktonic and biofilm-growing strains. AgNPs, AgNPs_mPEG, and AgNPs_mPEG_AK were characterized using a suite of spectroscopy and microscopy methods. Susceptibility to these treatments and AK was determined after 24 h and over time against 12 clinical multidrug-resistant (MDR)/extensively drug-resistant (XDR) isolates of Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The efficacy of the treatments alone and in combination with hyperthermia (1, 2, and 3 pulses at 41°C to 42°C for 15 min) was tested against the same planktonic strains using quantitative culture and against one P. aeruginosa strain growing on silicone disks using confocal laser scanning microscopy. The susceptibility studies showed that AgNPs_mPEG_AK was 10-fold more effective than AK alone, and bactericidal efficacy after 4, 8, 24, or 48 h was observed against 100% of the tested strains. The combination of AgNPs_mPEG_AK and hyperthermia eradicated 75% of the planktonic strains and exhibited significant reductions in biofilm formation by P. aeruginosa in comparison with the other treatments tested, except for AgNPs_mPEG_AK without hyperthermia. In conclusion, the combination of AgNPs_mPEG_AK and hyperthermia may be a promising therapy against MDR/XDR and biofilm-producing strains. IMPORTANCE Antimicrobial resistance (AMR) is one of the greatest public health challenges, accounting for 1.27 million deaths worldwide in 2019. Biofilms, a complex microbial community, directly contribute to increased AMR. Therefore, new strategies are urgently required to combat infections caused by AMR and biofilm-producing strains. Silver nanoparticles (AgNPs) exhibit antimicrobial activity and can be functionalized with antibiotics. Although AgNPs are very promising, their effectiveness in complex biological environments still falls below the concentrations at which AgNPs are stable in terms of aggregation. Thus, improving the antibacterial effectiveness of AgNPs by functionalizing them with antibiotics may be a significant change to consolidate AgNPs as an alternative to antibiotics. It has been reported that hyperthermia has a large effect on the growth of planktonic and biofilm-producing strains. Therefore, we propose a new strategy based on AgNPs functionalized with amikacin and combined with hyperthermia (41°C to 42°C) to treat AMR and biofilm-related infections. This study was supported by research grants from the Ministerio de Sanidad y Consumo, Instituto de Salud Carlos III (FIS 01162); la Marató TV3 (472/U/2018); the CaixaImpulse Program (Fundació LaCaixa); and the Spanish Network for Research in Infectious Diseases (REIPI RD19/0016).

Gene therapeutics; Gold nanoparticles; Safety Terapia génica; Nanopartículas de oro; Seguridad Teràpia gènica; Nanopartícules d'or; Seguretat Introduction: Gene therapy holds promise to cure various diseases at the fundamental level. For that, efficient carriers are needed for successful gene delivery. Synthetic ‘non-viral’ vectors, as cationic polymers, are quickly gaining popularity as efficient vectors for transmitting genes. However, they suffer from high toxicity associated with the permeation and poration of the cell membrane. This toxic aspect can be eliminated by nanoconjugation. Still, results suggest that optimising the oligonucleotide complexation, ultimately determined by the size and charge of the nanovector, is not the only barrier to efficient gene delivery. Methods: We herein develop a comprehensive nanovector catalogue comprising different sizes of Au NPs functionalized with two different cationic molecules and further loaded with mRNA for its delivery inside the cell. Results and Discussion: Tested nanovectors showed safe and sustained transfection efficiencies over 7 days, where 50 nm Au NPs displayed the highest transfection rates. Remarkably, protein expression was increased when nanovector transfection was performed combined with chloroquine. Cytotoxicity and risk assessment demonstrated that nanovectors are safe, ascribed to lesser cellular damage due to their internalization and delivery via endocytosis. Obtained results may pave the way to design advanced and efficient gene therapies for safely transferring oligonucleotides. We acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU) (RTI2018-099965-B-I00, AEI/FEDER,UE) proyectos de I+D+i de programación conjunta internacional MCIN/AEI (CONCORD, PCI2019-103436) cofunded by the European Union and Generalitat de Catalunya (2017-SGR-1431). ICN2 is supported by the Severo Ochoa program from Spanish MINECO (SEV-2017-0706) and is funded by the CERCA Programme/Generalitat de Catalunya.

Nanocarriers, and especially nanostructured lipid carriers (NLC), represent one of the most effective systems for topical drug administration. NLCs are biodegradable, biocompatible and provide a prolonged drug release. The glutamate release inhibitor Riluzole (RLZ) is a drug currently used for amyotrophic lateral sclerosis (ALS), with anti-proliferative effects potentially beneficial for diseases with excessive cell turnover. However, RLZ possesses low water solubility and high light-sensibility. We present here optimized NLCs loaded with RLZ (RLZ-NLCs) as a potential topical treatment. RLZ-NLCs were prepared by the hot-pressure homogenization method using active essential oils as liquid lipids, and optimized using the design of experiments approach. RLZ-NLCs were developed obtaining optimal properties for dermal application (mean size below 200 nm, negative surface charge and high RLZ entrapment efficacy). In vitro release study demonstrates that RLZ-NLCs allow the successful delivery of RLZ in a sustained manner. Moreover, RLZ-NLCs are not angiogenic and are able to inhibit keratinocyte cell proliferation. Hence, a NLCs delivery system loading RLZ in combination with natural essential oils constitutes a promising strategy against keratinocyte hyperproliferative conditions., This research was funded by the Spanish Ministry of Science and Innovation (PID2021-122187NB-C32 to M.G., PID2020-114477RB-I00 to C.S. and PID2021-126249OA-I00 to J.M. from the MCIN/ AEI /10.13039/501100011033).

[cat] La leucèmia mieloide aguda (LMA) és un grup heterogeni de malalties hematològiques que s'originen a partir de la proliferació clonal excessiva de cèl·lules precursores mieloides. Actualment, malgrat que la majoria de pacients inicialment responen al tractament, aproximadament dos terços pateixen recaigudes. En els últims anys, les cèl·lules mare leucèmiques (LSC) han tingut un especial interès a causa de les evidències que indiquen que són les principals responsables de la quimioresistència i les recaigudes. Per aquesta raó, és necessari erradicar selectivament les LSC amb noves estratègies terapèutiques dirigides que permetin superar la resistència a fàrmacs i millorar l’eficàcia del tractament reduint-ne els efectes secundaris. El present estudi es basa en l’ús de nanopartícules dirigides específicament al receptor de superfície CXCR4, el qual es troba sobreexpressat en aproximadament la meitat dels pacients amb LMA (CXCR4+), fet que s’ha relacionat amb mal pronòstic i un major risc de recidiva. En concret, en aquesta tesi s’estudien les nanotoxines polipeptídiques T22-DITOX-H6 i T22-PE24-H6, que contenen el domini de translocació i catalític de l’exotoxina diftèrica de Corynebacterium diphtheriae i el domini catalític desimmunitzat de l’exotoxina A provinent de Pseudomonas aeruginosa, respectivament. Ambdues toxines tenen la capacitat d’inactivar el factor d’elongació-2 eucariòtic, produint la inhibició de la síntesi proteica que, conseqüentment, provoca la mort cel·lular. L’objectiu principal d’aquesta tesi doctoral és avaluar la capacitat de les nanotoxines polipeptídiques T22-DITOX-H6 i T22-PE24-H6 d’eliminar selectivament les LSC CXCR4+ i de produir efecte antineoplàstic mitjançant la seva internalització a través del receptor CXCR4. Primerament, determinant l’efecte antineoplàstic de les nanotoxines polipeptídiques T22-DITOX-H6 i T22-PE24-H6 en línies cel·lulars de LMA, en models murins disseminats i en mostres de medul·la òssia (MO) de pacients amb LMA. Finalment, avaluant la relació entre l’expressió de CXCR4 i el fenotip LSC en les mostres de pacients de LMA. Els resultats obtinguts demostren que les nanotoxines avaluades exerceixen un potent efecte citotòxic in vitro en línies cel·lulars de LMA i que aquest és dependent de CXCR4 i està mediat per la inducció d'apoptosi. A més, l'administració intravenosa de dosis repetides, tant de T22-DITOX-H6 com de T22-PE24-H6 en models murins disseminats de LMA, indueix un potent efecte antineoplàstic in vivo, que redueix significativament la disseminació de la LMA, disminuint la càrrega leucèmica de les cèl·lules CXCR4+ sense toxicitat sistèmica associada. Altrament, en aquesta tesi doctoral s’ha comprovat que l’especificitat citotòxica de la nanotoxina T22-PE24-H6 sobre les cèl·lules de la LMA CXCR4+, provoca una reducció significativa de la viabilitat cel·lular en les mostres de pacients de LMA amb una alta expressió de CXCR4, però no té cap efecte en aquelles mostres amb baixa expressió de CXCR4 ni en una mostra de MO de donant sa. Convé destacar que els resultats obtinguts han evidenciat que el receptor CXCR4 es troba sobreexpressat en aquelles cèl·lules amb fenotip LSC, CD34+CD38-CD123+, i que la seva expressió correlaciona amb la de CD123, un marcador característic de LSC. Finalment, s’ha generat i validat un model PDX (Patient Derived Xenograft) derivat d’una mostra de MO CXCR4+ d’un pacient amb LMA, on poder avaluar posteriorment l’efecte de les nanotoxines dirigides a CXCR4. En resum, en aquesta tesi es proposa una nova teràpia basada en nanotoxines pel lliurament selectiu d’exotoxines bacterianes citotòxiques a les cèl·lules de LMA que sobreexpressen el receptor de superfície CXCR4, obrint una oportunitat terapèutica capaç d’eliminar selectivament les LSC, un subcompartiment cel·lular clau en la progressió de la LMA. Per això, aquesta teràpia selectiva milloraria el tractament actual dels pacients que pateixen LMA i que presenten sobreexpressió del receptor CXCR4, un subgrup de pacients amb major risc de presentar recaigudes i resistència a la quimioteràpia

A hydroxycinnamic acid derivative, namely ferulic acid (FA) has been successfully encapsulated in polymeric nanoparticles (NPs) based on poly(lactic-co-glycolic acid) (PLGA). FA-loaded polymeric NPs were prepared from O/W nano-emulsion templates using the phase inversion composition (PIC) low-energy emulsification method. The obtained PLGA NPs exhibited high colloidal stability, good drug-loading capacity, and particle hydrodynamic diameters in the range of 74 to 117 nm, depending on the FA concentration used. In vitro drug release studies confirmed a diffusion-controlled mechanism through which the amount of released FA reached a plateau at 60% after 6 hours-incubation. Five kinetic models were used to fit the FA release data as a function of time. The Weibull distribution and Korsmeyer-Peppas equation models provided the best fit to our experimental data and suggested quasi-Fickian diffusion behaviour. Moderate dose-response antioxidant and radical scavenging activities of FA-loaded PLGA NPs were demonstrated using the DPPH˙ assay achieving inhibition activities close to 60 and 40%, respectively. Cell culture studies confirmed that FA-loaded NPs were not toxic according to the MTT colorimetric assay, were able to internalise efficiently SH-SY5Y neuronal cells and supressed the intracellular ROS-level induced by H2O2 leading to 52% and 24.7% of cellular viability at 0.082 and 0.041 mg mL-1, respectively. The permeability of the NPs through the blood brain barrier was tested with an in vitro organ-on-a-chip model to evaluate the ability of the FA-loaded PLGA and non-loaded PLGA NPs to penetrate to the brain. NPs were able to penetrate the barrier, but permeability decreased when FA was loaded. These results are promising for the use of loaded PLGA NPs for the management of neurological diseases., The authors acknowledge the Agencia Estatal de Investigación for funding (Projects CTQ2017-84998-P and PID2021122187NB-C31) and the Instituto de Salud Carlos III (ISCIII) (CB06/01/1058 and CB06/01/0055). CIBER BBN is an initiative funded by the VI National R + D + I Plan 2008–2011, Iniciativa Ingenio 2010, Consolider Program, CIBER actions and financed by ISCIII with assistance from the European Regional Development Fund. The authors would like to thank Gemma Fabriàs’ research group for assistance and access to the cytometer instrument. The authors want to thank NANBIOSIS ICTS and the Nanostructured Liquid Characterization Unit (U12) for DLS and ζ-potential measurements, hyperspectral microscopy and dark-field imaging. The authors thank the Electron Microscopy Service from the National Centre of Biotechnology (CNB-CSIC), especially Beatriz Martín for sample preparation and TEM observations. The authors also acknowledge the “Grupo de Nanotecnología Farmacéutica” from the University of Barcelona in the Faculty of Pharmacy and Food Sciences which forms a R&D Associate Unit to CSIC.

Citation suggérée : Anses. (2022). Définition des nanomatériaux : enjeux, analyse et controverses (Saisine n° 2018-SA-0168). Maisons-Alfort : Anses, 128 p.; L’utilisation croissante des substances à l’état nanoparticulaire dans des secteurs d’activité trèsvariés a conduit les pouvoirs publics à faire évoluer la réglementation nationale et européenne pour prendre en compte leurs spécificités.La caractéristique dimensionnelle de ces substances, susceptible de conférer aux matériaux despropriétés ou comportements particuliers, laisse également entrevoir de probables différences en matière d’évaluation du risque (toxicité – écotoxicité et devenir dans l’environnement). Alors que ces substances sont souvent développées pour leurs propriétés spécifiques et considérées comme des vecteurs d’innovation, l’état des connaissances concernant les effets potentiels de ces substances sur l’environnement et la santé demeure généralement insuffisant pour en évaluer les risques (Anses 2014).En l’absence d’une définition pleinement partagée permettant de définir le périmètre des objetsconcernés, une première étape vers une meilleure connaissance a consisté à harmoniser levocabulaire employé (nano-objets, agrégats, agglomérats, nanomatériaux manufacturés, etc.) via la normalisation dans un premier temps, puis à établir une définition et des critères permettant de caractériser ces substances tels que leur taille, leur distribution, leur surface spécifique, etc.Au niveau européen, la recommandation du 18 octobre 2011 de la Commission européenne (CE)relative à la définition des nanomatériaux (2011/696/UE) a servi de référence à plusieurs reprisesdans les différents textes législatifs. Celle-ci s’est appuyée sur les travaux du Scenihr (ScientificCommittee on Emerging and Newly Identified Health Risks) portés sur ce sujet et publiés en 2010(Scenihr 2010).La Commission européenne avait proposé de s’appuyer sur cette définition pour adapter cellefigurant dans le Règlement n°1169/2011 relatif à l’information du consommateur sur les denréesalimentaires, notamment en y introduisant le seuil de 50 % de particules en nombre. Cetteproposition a été rejetée par le Parlement européen au motif que rien ne justifiait l’introduction d’un tel seuil, inadapté en l’occurrence pour répondre à la demande d’information du consommateur. En conséquence, seule la définition figurant dans le règlement relatif aux nouveaux aliments, à laquelle renvoie le Règlement n°1169/2011, s’applique dans le cadre des contrôles opérés par la Direction générale de la consommation, de la concurrence et de la répression des fraudes (DGCCRF) pour s’assurer de la bonne information du consommateur sur le caractère nanométrique des ingrédients mis en œuvre. Cette définition ne comporte pas de seuil, de sorte qu’un ingrédient est déclaré « nano » dès lors que la présence de nanoparticules est avérée. Dans la pratique, selon la méthodologie de contrôle développée par le Service commun des laboratoires, un ingrédient est considéré correspondre à un nanomatériau lorsque 10 % au moins des particules en présence sont de taille nanométrique.Actuellement, la définition de « nanomatériau » peut différer d’un règlement européen à l’autre(règlements sur les produits biocides, sur les produits cosmétiques, sur les nouveaux aliments, sur l’information des consommateurs sur les denrées alimentaires, sur les dispositifs médicaux). Les travaux portant sur la révision des annexes du Règlement 1907/2006 « REACH » pour l’adapter aux substances sous forme nanoparticulaire ont été publiés en 2018 (Règlement UE 2018/1881). Le projet de texte de ces annexes a été voté par la Commission en comité le 26 avril 2018 et est entré en application le 1 er janvier 2020. Le texte se réfère à la recommandation de définition européenne.Les définitions actuelles proposées dans la recommandation de la Commission de 2011 et dans les différents règlements comportent des différences et des imprécisions (seuil de 50 % en nombre, taille, notions d’insolubilité ou de bio-persistance dans le règlement cosmétique, etc.), régulièrement mises en avant par les parties prenantes. Celles-ci souhaitent l’établissement d’une définition plus claire et harmonisée. La Commission européenne avait annoncé dans plusieurs communications relatives à cette recommandation son intention de la réviser avant décembre 2014 pour mieux prendre en compte les spécificités de ces substances, l’avancée des connaissances et préciser certains points de la définition.Le Joint Research Center (JRC), service de recherche de la Commission européenne, a publié en2014 un premier rapport comportant des propositions relatives aux critères pouvant être pris enconsidération pour définir les nanomatériaux (Rauscher et al. 2015). Plus récemment, en préparation de la proposition de définition par la Commission européenne, le JRC a publié début 2019 un document support définissant les termes et concepts utiles liés à la définition (Rauscher, Roebben, et al. 2019) puis un autre rapport relatif cette fois-ci aux techniques analytiques d’identification des nanomatériaux (Rauscher, Mech, et al. 2019).Après plusieurs phases de discussion engagées dès 2012, la Commission a ouvert une courtephase de consultation publique (du 06/05/2021 au 30/06/2021) afin de recueillir les avis quant aux propositions d’évolution de la définition européenne datant de 2011. Cette phase de consultation s’est achevée par la publication d’une nouvelle Recommandation de définition le 10 juin 2022.

The interaction of amorphous silica nanoparticles with phospholipid monolayers and bilayers has received a great deal of interest in recent years and is of importance for assessing potential cellular toxicity of such species, whether natural or synthesized for the purpose of nanomedical drug delivery and other applications. This present communication studies the rate of silica nanoparticle adsorption on to phospholipid monolayers in order to extract a heterogeneous rate constant from the data. This rate constant relates to the initial rate of growth of an adsorbed layer of nanoparticles as SiO2 on a unit area of the monolayer surface from unit concentration in dispersion. Experiments were carried out using the system of dioleoyl phosphatidylcholine (DOPC) monolayers deposited on Pt/Hg electrodes in a flow cell. Additional studies were carried out on the interaction of soluble silica with these layers. Results show that the rate constant is effectively constant with respect to silica nanoparticle size. This is interpreted as indicating that the interaction of hydrated SiO2 molecular species with phospholipid polar groups is the molecular initiating event (MIE) defined as the initial interaction of the silica particle surface with the phospholipid layer surface promoting the adsorption of silica nanoparticles on DOPC. The conclusion is consistent with the observed significant interaction of soluble SiO2 with the DOPC layer and the established properties of the silica–water interface., We acknowledge EU for supporting ENNSATOX GA No. 229244, HISENTS GA No. 685817, and SABYDOMA GA No 862296.

Cyclometalated Ir(III) complexes hold great promise as an alternative to platinum metallodrugs for the therapy and diagnosis of cancer. However, their low aqueous solubility and poor cell membrane permeability are obstacles for in vivo applications. Here we have encapsulated for the first time, using polyurethane-polyurea hybrid nanocapsules (NCs), two phosphorescent tris-cyclometalated Ir(III) complexes incorporating deprotonated 2-arylbenzimidazole ligands, Ir1 and Ir2. Ir(III)-Loaded nanocapsules (NC-Ir1 and NC-Ir2) showed a roughly round shape and controlled particle size distribution around 18 nm. The photophysical properties of aqueous solutions of NCs were similar to those of the free complexes in CH2Cl2, which accounts for the hydrophobic and protective environment generated by the nanoparticles around the cargo. Nanoencapsulation had also a positive effect on the cellular uptake of the metallodrugs and NCs were found to be highly cytotoxic towards several cancer cell lines, whereas Ir(III) complexes alone were found to be inactive. A strong tumor growth inhibition effect was also found in 3D tumorsphere cancer models owing to the high penetration capacity of small NCs. Finally, the mode of cell death of the NCs was found to be related to oncosis, and the mitochondrial dysfunction and generation of extensive oxidative stress appeared to be also involved in the mechanism of action of these novel nanomedicines.

The SARS-CoV-2 outbreaks highlighted the need for effective, reliable, fast, easy-to-do and cheap diagnostics procedures. We pragmatically experienced that an early positive-case detection, inevitably coupled with a mass vaccination campaign, is a milestone to control the COVID-19 pandemic. Gold nanoparticles (AuNPs) can indeed play a crucial role in this context, as their physicochemical, optics and electronics properties are being extensively used in photothermal therapy (PTT), radiation therapy (RT), drug delivery and diagnostic. AuNPs can be synthesized by several approaches to obtain different sizes and shapes that can be easily functionalized with many kinds of molecules such as antibodies, proteins, probes, and lipids. In addition, AuNPs showed high biocompatibility making them useful tool in medicine field. We thus reviewed here the most relevant evidence on AuNPs as effective way to detect the presence of SARS-CoV-2 antigens. We trust future diagnostic efforts must take this 'old-fashioned' nanotechnology tool into consideration for the development and commercialization of reliable and feasible detection kits.

The global market for nanoparticles represents a production of 11 million tons per year according to the European Commission. Among different production methods, flame synthesis is considered a promising technology for producing nanoparticles with fine control over their characteristics. In this context, the goal of this thesis is to develop optical diagnostics to study the spatial evolution of characteristics of a population of TiO2 particles produced along the flame, in order to better understand their formation mechanism and create a database for the development of numerical models. First, laser-induced emission (LIE) of titanium dioxide (TiO2) nanoparticles is studied to demonstrate the feasibility of laser-induced incandescence (LII) technique on these particles. LII is a quasinon-intrusive technique that characterizes the volume fraction of particles (fv) and primary particle size. It is traditionally used for in-situ characterization of soot formation in flames, but its feasibility on TiO2 nanoparticles remains to be demonstrated. If feasible, it could provide new insights into the synthesis process of metal oxide nanoparticles in spray flames and thus allow a spatial description of the production of TiO2 nanoparticles. To verify the feasibility of the LII technique, both high-purity TiO2 nanoparticles and hydrogen flame-generated TiO2 nanoparticles are considered using two particle-generation systems: the first directly injects particles into a non-reactive environment, and the second synthesizes particles via a reactive environment. The latter applies a new version of the Yale diffusion burner that stabilizes the pre-vaporized diffusion flame of titanium isopropoxide (TTIP)/H2/Ar. In both systems, the particles are irradiated with a top-hat laser in the UV range, thus ensuring absorption and heating of the particles. A detection system equipped with a spectrometer and a photomultiplier tube (PMT) is also used to identify the spectral and temporal characteristics of the LIE of the TiO2 nanoparticles. Different laser fluences and acquisition times are considered to observe the different signal contributions from the nanoparticles. The nature of the signal is investigated by comparing it to theoretical results and reference results obtained from carbon black nanoparticles.Specially, the laser-induced emission of TiO2 nanoparticles exhibits non-LII components during the first 100 nanoseconds after the laser interaction. At low laser fluence, these features can be interpreted as laser-induced fluorescence (LIF). With high laser fluence, phase-selective laser-induced breakdown spectroscopy (PS-LIBS) can occur due to possible surface vaporization of the particles. As LIF and PS-LIBS signals are characterized by a short lifetime, delayed acquisition is considered to avoid these interferences. The LII nature of the temporally delayed emission signal is demonstrated first by confirming the spectral behavior of a black body. Secondly, the temporal evolution of the signal decay rate and the inverse temperature is analyzed and confirms as an LII-type behavior. In the considered configurations, the presence of carbon on the nanoparticles of TiO2 is unlikely. Therefore, the contribution of carbonaceous materials to the LII signal can be assumed negligible, thus demonstrating the feasibility of the LIItechnique for TiO2 nanoparticles.Next, a quantitative characterization of the production of titanium dioxide nanoparticles in flames is carried out. For this, the LII signal is converted into a volume fraction fv, which requires the knowledge of the effective temperature Teff reached by the particles during the laser irradiation and of the absorption function E(mλ). Since these two quantities are strongly related, it is necessary to have information on one in order to estimate the other. However, there is a large variability in the literature data for the absorption function E(mλ) for TiO2, whose optical properties strongly depend on particle characteristics such as geometry, crystalline structure, and state of matter. To address this issue, a new approach to estimate the spectral dependence of the absorption function is proposed from LII measurements. This method is first validated for carbon black nanoparticles, for which data are available in the literature. It is then applied to high-purity and flame-synthesized TiO2 nanoparticles. Once the information on E(mλ) is available, the effective temperature of the particles can be deduced. Finally, the spatial distribution effects of the effective temperature and the absorption function on the measurement of the volume fraction of TiO2 in our reference flame are studied. The results of the measurements are compared to those from a numerical simulation representative of state-of-the-art modeling. The comparisons of normalized fv fields provide a first indication for improving numerical models.; Le marché global des nanoparticules représente une production de 11 millions de tonnes par an d’après la Commission européenne. Parmi les différentes méthodes de production, la synthèse de celles-ci dans des flammes est considérée comme une technologie très prometteuse permettant un contrôle fin des caractéristiques des particules produites. Dans ce contexte, l’objectif de ce travail est de développer des diagnostiques d’optiques permettant l’étude de l’évolution spatiale des caractéristiques d’une population de particules de TiO2 produites le long de la flamme ; cela, afin, à la fois de mieux comprendre leur mécanisme de formation, et de créer une base de données pour le développement de modèles numériques. Tout d’abord, l’émission induite par laser (LIE) de nanoparticules de dioxyde de titane (TiO2) est étudiée pour montrer la faisabilité de la technique d’incandescence induite par laser (LII) sur celles-ci. Cette technique permet de caractériser de façon quasi-non intrusive la fraction volumique des particules fv et la taille de particules primaire. Elle est classiquement utilisée pour la caractérisation in-situ de la formation de suies dans les flammes, mais sa faisabilité sur de nanoparticules de TiO2 reste encore à démontrer. Dans le cas où elle le serait, elle pourrait fournir de nouvelles informations sur le processus de synthèse des oxydes métalliques dans les flammes spray et permettre ainsi une description spatiale de la production de nanoparticules de TiO2.Pour vérifier la faisabilité de la technique LII, on considère à la fois des nanoparticules de TiO2 de haute pureté et des nanoparticules de TiO2 générées par une flamme d’hydrogène en utilisant deux systèmes de génération de particules : l’un injecte directement des particules dans un milieu non réactif et l’autre synthétise les particules via un milieu réactif. Pour ce dernier, une version inspirée du brûleur de Yale est utilisée. Elle permet la stabilisation de flamme de diffusion pré-vaporisée d’isopropoxyde de titane (TTIP)/H2/Ar. Dans les deux systèmes, les particules sont irradiées à l’aide d’un laser de type top-hat dans la gamme UV, assurant ainsi l’absorption et le chauffage des particules. Un système de détection équipé d’un spectromètre et d’un tube photomultiplicateur (PMT) est également utilisé pour identifier les caractéristiques spectrales et temporelles de LIE des nanoparticules de TiO2. Différentes fluences du laser et durées d’acquisition sont prises en compte pour observer les différentes contributions du signal provenant des nanoparticules TiO2. La nature du signal est étudiée en la comparant aux résultats théoriques et à des résultats de référence obtenus à partir de nanoparticules de noir de carbone. Plus précisément, l’émission induite par laser des nanoparticules de TiO2 présente des composantes non-LII pendant les 100 premières nanosecondes après l’interaction avec le laser. A faible fluence laser, le signal peut être interprété comme une fluorescence induite par laser (LIF). Pour une fluence laser élevée, la spectroscopie par claquage induit par laser sélectif en phase (PS-LIBS) peut se produire en raison d’une éventuelle vaporisation de la surface des particules.Comme les signaux LIF et PS-LIBS sont caractérisés par une courte durée de vie, une acquisition retardée est envisagée pour éviter ces interférences. La nature LII du signal d’émission décalée dans le temps est démontrée premièrement, en confirment le comportement spectral d’un corps noir. Deuxièmement, l’évolution temporelle du taux de décroissance du signal et de la température inverse est analysée et confirme un comportement du type LII. Dans les configurations considérées, une présence de carbone sur les nanoparticules de TiO2 est peu probable. De ce fait, la contribution de matériaux carbonés au signal LII peut être supposée négligeable, démontrant ainsi la faisabilité de la technique LII pour des particules de TiO2.Ensuite, une caractérisation quantitative de la production de nanoparticules de TiO2 dans des flammes a été réalisée. Pour cela, le signal LII est converti en fraction de volume fv. Cela nécessite donc la connaissance de la température effective Teff atteinte par les particules pendant l’irradiation du laser et de la fonction d’absorption E(mλ). Les deux grandeurs étant fortement liées, il est nécessaire de disposer d’une information sur l’une pour estimer la deuxième. Cependant, une grande variabilité caractérise les données de la littérature pour la fonction E(mλ) pour le TiO2, dont les propriétés optiques dépendent fortement des caractéristiques des particules telles que leur géométrie, la structure cristalline et l’état de la matière. Afin de répondre à cette problématique, une nouvelle approche pour estimer la forme spectrale de la fonction d’absorption est proposée à partir des mesures LII. Cette méthode est d’abord validée pour les nanoparticules de noir de carbone pour lesquelles des données sont disponible dans la littérature. Elle est ensuite appliquée aux nanoparticules de TiO2 de haute pureté et de TiO2 synthétisées via la flamme. Une fois l’information sur E(mλ) disponible, la température effective des particules peut être déduite. Enfin, les effets de la distribution spatiale de la température effective et de la fonction d’absorption sur la mesure de la fraction volumique de TiO2 dans notre flamme de référence ont été étudiés. Les résultats issus des mesures sont comparés à ceux issus d’une simulation numérique représentative de l’état-de-l‘art sur le sujet en termes de modélisation. Les comparaisons des champs de fv normalisés fournissent une première indication pour l’amélioration des modèles numériques.

Titanium dioxide (TiO2) nanoparticles are the subject of numerous studies and controversies on the risks they could generate in the environment and on human health. They are electron dense nanoparticles that have a chemical signature and are thus detectable by Transmission Electron Microscopy (TEM) and Secondary Ion Mass Spectrometry (NanoSIMS 50). Moreover, abundant in sunscreens (for anti-ultraviolet sunscreen filter properties), they constitute a good material of study for the development of the imaging by correlation TEM/NanoSIMS.As TEM uses electrons and NanoSIMS uses ions, it was necessary to define a sample preparation protocol (sunscreen applied on human skin) adapted to both instruments for the detection, characterization and localization of few nanometers nano-objects in sections of a few tens of nanometers thickness. The data obtained and processed have allowed the development of the overlay of TEM and NanoSIMS images on the one hand and to lead to a 3D reconstruction of objects smaller than the thickness of the section on the other hand. It appears that the TEM/NanoSIMS correlation completes, reinforces and brings more results than each instrument provides, and that aggregated or isolated nanoparticles are retained by the corneocytes at the skin surface.; Les nanoparticules de dioxyde de titane (TiO2) font l’objet de nombreux travaux et controverses sur les risques qu’elles pourraient engendrer dans l’environnement et sur la santé humaine. Ce sont des nanoparticules denses aux électrons qui possèdent une signature chimique et sont ainsi repérables au Microscope Electronique à Transmission (MET) et au Spectromètre de Masse d’Ions Secondaires (NanoSIMS 50). De plus, abondantes dans les crèmes solaires (pour leurs propriétés de filtre anti ultra-violets), elles constituent un bon matériel d’étude pour la mise au point de l’imagerie par corrélation MET/NanoSIMS.Comme le MET utilise des électrons et le NanoSIMS des ions, il a fallu définir un protocole de préparation d’échantillon (crème solaire appliquée sur la peau humaine) adapté aux deux instruments pour la détection, la caractérisation et la localisation de nano-objets de quelques nanomètres dans des coupes de quelques dizaines de nanomètres d’épaisseur. Les données obtenues et traitées ont permis de mettre au point la superposition des images MET et NanoSIMS d’une part et de conduire à une reconstruction 3D d’objets de taille inférieure à l’épaisseur de la coupe d’autre part. Il en ressort que la corrélation MET/NanoSIMS complète, renforce et apporte davantage de résultats que ce que fournit chaque instrument isolément. Il ressort également que les nanoparticules isolées ou agrégées sont retenues par la barrière cornéocytaire à la surface de la peau.

Recently, nanotechnology and nanoparticles (NPs) such as AgNPs and AuNPs have become important in analytical chemistry due to their great potential to improve the performance of electrochemical sensors. In this work, Ag and Au nanoparticles have been synthesized using a green route in which a grape stalk waste extract is used as a reducing agent to obtain metallic nanoparticles. These NPs were used to customize the surface of commercial screen-printed electrodes (SPCNFEs). The spin-coating method was used to modify commercial SPCNFEs under a nitrogen atmosphere. The resulting electrodes were used in a determination study of Cd(II), Pb(II), and U(VI) with differential pulse anodic stripping voltammetry (DPASV). The customized green AgNPs and AuNPs electrodes presented higher sensitivity and electroanalytical performance than the non-modified SPCNFE. The results showed that the best analytical parameters were obtained with the green, silver nanoparticle SPCNFEs, with a LOD of 0.12 μg L−1 for Pb(II), which is a lower value compared to the most restrictive regulation guidelines. Additionally, the U(VI) ion was successfully determined using the developed G-AgNPs-SPCNFE in spiked tap water, showing comparable results with the ICP-MS technique.

Los nanocompuestos porosos multifuncionales, como la celulosa bacteriana (BC), han suscitado el interés de muchos investigadores por sus posibles usos en biomedicina. Las estrategias actuales pretenden añadir funcionalidades adicionales a la BC, como características antibacterianas, antifúngicas, antioxidantes y antiinflamatorias, mediante el uso de nanopartículas (NPs) o polímeros naturales. El objetivo de esta tesis es desarrollar nuevos nanocompuestos de BC mediante la adición de NPs de ceria y de quitosano. Por un lado, las NPs de ceria muestran un uso potencial en biomedicina. Por otro lado, el quitosano es un polímero natural con una estructura similar a la celulosa, pero con atractivas propiedades antibacterianas, antifúngicas, antioxidantes y antiinflamatorias. En esta tesis, el trabajo se centró en la producción de nanocompuestos funcionales utilizando películas de BC como matriz, y de NPs de ceria y quitosano como cargas. En primer lugar, se estudiaron diferentes enfoques para la síntesis de NPs de ceria (coprecipitación y descomposición térmica). Se prestó especial atención a la morfología y la estabilidad de las NPs de ceria en presencia de distintos tensioactivos. Los mejores resultados se obtuvieron con el método de coprecipitación, que proporcionó NPs en un amplio rango de tamaños (2 a 7 nm) con alta cristalinidad. Se utilizaron diferentes moléculas con propiedades interesantes, como el ácido glutámico o el quitosano, como ligandos superficiales de las NPs añadiéndolos durante la síntesis o poco después. Estos últimos mostraron mejores resultados, aunque en ambos casos los estados de aglomeración de las NPs se vieron comprometidos. A continuación, se funcionalizaron las películas de BC añadiendo ceria y quitosano en el proceso de biosíntesis o sintetizando las NPs sobre películas previamente producidas. La carga de NPs en las películas de celulosa bacteriana se confirmó mediante ambos enfoques, pero se consiguieron mayores cargas cuando las partícula Multifunctional porous nanocomposites such as bacterial cellulose (BC) have gathered the interest of many researchers for their potential uses in wound dressing scaffolds or drug delivery. Current strategies aim to add additional functionalities to BC such as antibacterial, antifungal, antioxidant, and anti-inflammatory characteristics by using nanoparticles (NPs) or natural polymers. This thesis aims to develop novel BC nanocomposites by adding ceria NPs and chitosan polymers. On one hand, ceria NPs show potential use in biomedicine. On the other hand, chitosan is a natural polymer with a similar structure to cellulose but with appealing antibacterial, antifungal, antioxidant, and anti-inflammatory properties. In this thesis, activities focused on the production of functional nanocomposites using BC films as a matrix, and ceria NPs and chitosan as fillers. First, different approaches for the synthesis of ceria NPs were studied (coprecipitation and thermal decomposition). Particular attention was paid to the morphology and the stability of ceria NPs in the presence of different surfactants. Best results were obtained for the coprecipitation method providing NPs in a wide range of sizes (2 to 7 nm) with high crystallinity. Different molecules having interesting properties such as glutamic acid or chitosan were used as surface ligands for the NPs adding them during the synthesis or soon after. The latter showed better results although in both cases the agglomeration states of the NPs were compromised. Next, BC films were functionalized by adding ceria and chitosan into the biosynthesis process or by synthesizing the NPs on top of previously produced films. The loading of NPs into bacteria cellulose films was confirmed by both approaches but higher loadings were achieved when particles were grown directly onto produced BC films. Besides, films showed a decrease in the mechanical resistance resulting from the structural loss of cellulose.

The long quest for efficient drug administration has been looking for a universal carrier that can precisely transport traditional drugs, new genomic and proteic therapeutic agents. Today, researchers have found conditions to overcome the two main drug delivery dilemmas. On the one side, the versatility of the vehicle to efficiently load, protect and transport the drug and then release it at the target place. On the other hand, the questions related to the degree of PEGylation which are needed to avoid nanoparticle (NP) aggregation and opsonization while preventing cellular uptake. The development of different kinds of lipidic drug delivery vehicles and particles has resulted in the development of ionizable lipid nanoparticles (iLNPs), which can overcome most of the typical drug delivery problems. Proof of their success is the late approval and massive administration as the prophylactic vaccine for SARS-CoV-2. These ILNPs are built by electrostatic aggregation of surfactants, the therapeutic agent, and lipids that self-segregate from an aqueous solution, forming nanoparticles stabilized with lipid polymers, such as PEG. These vehicles overcome previous limitations such as low loading and high toxicity, likely thanks to low charge at the working pH and reduced size, and their entry into the cells via endocytosis rather than membrane perforation or fusion, always associated with higher toxicity. We herein revise their primary features, synthetic methods to prepare and characterize them, pharmacokinetic (administration, distribution, metabolization and excretion) aspects, and biodistribution and fate. Owing to their advantages, iLNPs are potential drug delivery systems to improve the management of various diseases and widely available for clinical use., We acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU) (RTI2018-099965- B-I00, AEI/FEDER,UE) proyectos de I+D+i de programación conjunta internacional MCIN/AEI (CONCORD, PCI2019- 103436) cofunded by the European Union and Generalitat de Catalunya (2017-SGR-1431). ICN2 is supported by the Severo Ochoa program from Spanish MINECO (SEV-2017-0706) and is funded by the CERCA Programme/Generalitat de Catalunya.

This study consists of the fabrication of structures of 2 ?m porous silicon. These structures in post processing have the capacity to hold nanoparticles inside with the aim of producing green hydrogen by catalysis. First, a sample preparation is made based on blank silicon wafers. The purpose of this preparation is to determine the location where the pores will be created. Then an electrochemical etching process is carried out to create 250 ?m depth pores. By reducing the amount of silicon in the walls, a process is used to increase the thickness of the pores. Then, a membrane is created where the silicon is removed from the opposite side of the sample, so these pores reach the end of the sample. Once the process is complete, it is oxidised and nanoparticles can be deposited inside it. The main objective of this study is to fabricate macroporous silicon and then characterize the results in order to draw conclusions to improve the process. Este estudio consiste en la fabricación de estructuras de silicio poroso de 2 um. Estas estructuras en postproceso tienen la capacidad de albergar nanopartículas en su interior con el objetivo de producir hidrógeno verde por catálisis. En primer lugar, se realiza una preparación de la muestra a partir de obleas de silicio. El objetivo de esta preparación es determinar el lugar donde se crearán los poros. A continuación, se lleva a cabo un proceso de ataque electroquímico para crear poros de 250 um de profundidad. Después se reduce la cantidad de silicio de las paredes mediante un proceso de ensanchamiento de los poros. A continuación, se crea una membrana en la que se elimina el silicio del lado opuesto de la muestra, de modo que estos poros llegan hasta el final de la muestra. Una vez finalizado el proceso, se oxida y se pueden depositar nanopartículas en su interior. El objetivo principal de este estudio es fabricar silicio macroporoso y luego caracterizar los resultados para sacar conclusiones que permitan mejorar el proceso. Aquest estudi consisteix a fabricar estructures de silici porós de 2 um. Aquestes estructures en postprocés tenen capacitat per albergar nanopartícules al seu interior amb l'objectiu de produir hidrogen verd per catàlisi. En primer lloc, es fa una preparació de la mostra a partir d'oblees de silici. L´objectiu d´aquesta preparació és determinar el lloc on es crearan els porus. A continuació, es duu a terme un procés d'atac electroquímic per crear porus de 250 um de profunditat. Després es redueix la quantitat de silici de les parets mitjançant un procés d'eixamplament dels porus. A continuació, es crea una membrana on s'elimina el silici del costat oposat de la mostra, de manera que aquests porus arriben fins al final de la mostra. Un cop finalitzat el procés, s'oxida i es poden dipositar nanopartícules a l'interior. L'objectiu principal d'aquest estudi és fabricar silici macroporós i caracteritzar els resultats per treure conclusions que permetin millorar el procés.

Les nanopartícules de carboni fluorescents o els punts quàntics de carboni (CQD) són una nova classe de nanomaterials de carboni que han sorgit recentment i han despertat molt d'interès com a competidors potencials dels punts quàntics de semiconductors convencionals. A més de les seves propietats òptiques comparables, els CQD tenen els avantatges desitjats de baixa toxicitat, baix cost respectuós amb el medi ambient i rutes sintètiques senzilles. A més, la passivació superficial i la funcionalització dels CQD permeten el control de les seves propietats fisicoquímiques. L'objectiu d'aquest treball és la síntesi de CQD per detectar i quantificar l'elastasa en solució. Per fer-ho anclem un pèptid específic a la superfície dels CQD per reconèixer l'enzim. Las nanopartículas de carbono fluorescentes o puntos cuánticos de carbono (CQD) son una nueva clase de nanomateriales de carbono que han surgido recientemente y han ganado mucho interés como competidores potenciales de los puntos cuánticos de semiconductores convencionales. Además de sus propiedades ópticas comparables, los CQD tienen las ventajas deseadas de baja toxicidad, respeto por el medio ambiente, bajo costo y rutas sintéticas simples. Además, la pasivación superficial y la funcionalización de los CQD permiten el control de sus propiedades fisicoquímicas. El objetivo de este trabajo es la síntesis de CQDs para detectar y cuantificar elastasa en solución. Para ello, anclamos un péptido específico en la superficie de los CQD para reconocer la enzima. Fluorescent carbon nanoparticles or carbon quantum dots (CQDs) are a new class of carbon nanomaterials that have emerged recently and have garnered much interest as potential competitors to conventional semiconductor quantum dots. In addition to their comparable optical properties, CQDs have the desired advantages of low toxicity, environmental friendliness low cost, and simple synthetic routes. Moreover, surface passivation and functionalization of CQDs allow for the control of their physicochemical properties. The aim of this work is the synthesis of CQDs to detect and quantify elastase in solution. To do that we anchor a specific peptide on the surface of the CQDs to recognize the enzyme. Electrochemical tests were performed to study the electrochemical activity such as cyclovoltammetry and impedance spectroscopy. Incoming