Partículas codificadas

La presente invención se refiere a una partícula codificada. Específicamente, la partícula codificada según la presente invención, comprende: a) al menos un núcleo metálico; b) un agente de marcaje unido a la superficie de dicho núcleo metálico, proporcionando un núcleo metálico marcado; c) una capa externa de un material inerte que encapsula a dicho núcleo metálico marcado; y d) al menos una biomolécula directamente o indirectamente unida a dicha capa externa. Además, la presente invención se refiere a un método para la preparación de una partícula codificada. Además, la presente invención se refiere a un método para la preparación de una microesfera y a la microesfera obtenida por el método. Además, la presente invención se refiere a un método para detectar materiales biológicos. Adicionalmente, la presente invención se refiere al uso de una partícula codificadaPeer reviewedUniversidad de VigoB1 Patente sin examen previ

Partículas codificadas

La presente invención se refiere a una partícula codificada. Específicamente, la partícula codificada según la presente invención, comprende: a) al menos un núcleo metálico; b) un agente de marcaje unido a la superficie de dicho núcleo metálico, proporcionando un núcleo metálico marcado; c) una capa externa de un material inerte que encapsula a dicho núcleo metálico marcado; y d) al menos una biomolécula directamente o indirectamente unida a dicha capa externa. Además, la presente invención se refiere a un método para la preparación de una partícula codificada. Además, la presente invención se refiere a un método para la preparación de una microesfera y a la microesfera obtenida por el método. Además, la presente invención se refiere a un método para detectar materiales biológicos. Adicionalmente, la presente invención se refiere al uso de una partícula codificadaPeer reviewedUniversidad de VigoB1 Patente sin examen previ

Manipulating chemistry through nanoparticle morphology

We demonstrate that the protonation chemistry of molecules adsorbed at nanometer distances from the surface of anisotropic gold nanoparticles can be manipulated through the effect of surface morphology on the local proton density of an organic coating. Direct evidence of this remarkable effect was obtained by monitoring surface-enhanced Raman scattering (SERS) from mercaptobenzoic acid and 4-aminobenzenethiol molecules adsorbed on gold nanostars. By smoothing the initially sharp nanostar tips through a mild thermal treatment, changes were induced on protonation of the molecules, which can be observed through changes in the measured SERS spectra. These results shed light on the local chemical environment near anisotropic colloidal nanoparticles and open an alternative avenue to actively control chemistry through surface morphology.LL and LML-M acknowledge funding from European Commission Grant (EUSMI 731019). Funding is also acknowledged from the Spanish MINECO (MAT2017-86659-R and MDM-2017-0720 to LML-M; MAT2017-88492-R and SEV2015-0522 to JGA) and the European Research Council (Advanced Grant 787510 4DBIOSERS to LML-M; Advanced Grant 789104-eNANO to JGA)

Plasmonic supercrystals

For decades, plasmonic nanoparticles have been extensively studied due to their extraordinary properties, related to localized surface plasmon resonances. A milestone in the field has been the development of the so-called seed-mediated growth method, a synthetic route that provided access to an extraordinary diversity of metal nanoparticles with tailored size, geometry and composition. Such a morphological control came along with an exquisite definition of the optical response of plasmonic nanoparticles, thereby increasing their prospects for implementation in various fields. The susceptibility of surface plasmons to respond to small changes in the surrounding medium or to perturb (enhance/quench) optical processes in nearby molecules, has been exploited for a wide range of applications, from biomedicine to energy harvesting. However, the possibilities offered by plasmonic nanoparticles can be expanded even further by their careful assembly into either disordered or ordered structures, in 2D and 3D. The assembly of plasmonic nanoparticles gives rise to coupling/hybridization effects, which are strongly dependent on interparticle spacing and orientation, generating extremely high electric fields (hot spots), confined at interparticle gaps. Thus, the use of plasmonic nanoparticle assemblies as optical sensors have led to improving the limits of detection for a wide variety of (bio)molecules and ions. Importantly, in the case of highly ordered plasmonic arrays, other novel and unique optical effects can be generated. Indeed, new functional materials have been developed via the assembly of nanoparticles into highly ordered architectures, ranging from thin films (2D) to colloidal crystals or supercrystals (3D). The progress in the design and fabrication of 3D supercrystals could pave the way toward next generation plasmonic sensors, photocatalysts, optomagnetic components, metamaterials, etc. In this Account, we summarize selected recent advancements in the field of highly ordered 3D plasmonic superlattices. We first analyze their fascinating optical properties for various systems with increasing degrees of complexity, from an individual metal nanoparticle through particle clusters with low coordination numbers to disordered self-assembled structures and finally to supercrystals. We then describe recent progress in the fabrication of 3D plasmonic supercrystals, focusing on specific strategies but without delving into the forces governing the self-assembly process. In the last section, we provide an overview of the potential applications of plasmonic supercrystals, with a particular emphasis on those related to surface-enhanced Raman scattering (SERS) sensing, followed by a brief highlight of the main conclusions and remaining challenges.Agencia Estatal de Investigación | Ref. MAT2017-86659-RMinisterio de Economía, Industria y Competitividad | Ref. MAT2016-77809-

Structural and magnetic studies in ferrihydrite nanoparticles formed within organic-inorganic hybrid matrices

6 pages, 6 figures, 1 table.We report detailed transmission electron microscopy, high resolution transmission electron microscopy (HRTEM), and scanning transmission electron microscopy/energy dispersive x-ray spectroscopy (STEM/EDS) studies on ferrihydrite nanoparticles in an organic-inorganic matrix. The Fourier transform of HRTEM images indicates the existence of six-line ferrihydrite. Combined STEM and EDS studies give further confirmation of the presence of iron in the observed particles and its absence in the matrix. The derived mean particle size and size distribution is 4.7±0.2 nm with a lognormal deviation of s=0.4±0.1. These values were used for analysis of magnetic measurements, yielding the determination of the anisotropy constant Keff=4×105 erg/cm3 and the power relation between the number of iron ions per particle and the number of uncompensated ones p≈1/3. This value indicates that the uncompensated spins are mainly randomly distributed at the surface. According to this model, a shell thickness of about one ferrihydrite unit cell is estimated.The financial support from FCT, POCTI/ CTM/46780/02, research grant MAT2004-03395-C02-01 from the Spanish CICYT, and Acción Integrada Luso- Española E-105/04 is gratefully recognized. One of the authors (N.J.O.S.) acknowledges a grant from FCT (Grant No. SFRH/BD/10383/2002). Another author (L.M.L.-M.) acknowledges support from Xunta de Galicia (Grant No. PGIDIT03TMT30101PR).Peer reviewe

Machine learning‐assisted high‐throughput SERS classification of cell secretomes

During the response to different stress conditions, damaged cells react in multiple ways, including the release of a diverse cocktail of metabolites. Moreover, secretomes from dying cells can contribute to the effectiveness of anticancer therapies and can be exploited as predictive biomarkers. The nature of the stress and the resulting intracellular responses are key determinants of the secretome composition, but monitoring such processes remains technically arduous. Hence, there is growing interest in developing tools for noninvasive secretome screening. In this regard, it has been previously shown that the relative concentrations of relevant metabolites can be traced by surface-enhanced Raman scattering (SERS), thereby allowing label-free biofluid interrogation. However, conventional SERS approaches are insufficient to tackle the requirements imposed by high-throughput modalities, namely fast data acquisition and automatized analysis. Therefore, machine learning methods were implemented to identify cell secretome variations while extracting standard features for cell death classification. To this end, ad hoc microfluidic chips were devised, to readily conduct SERS measurements through a prototype relying on capillary pumps made of filter paper, which eventually would function as the SERS substrates. The developed strategy may pave the way toward a faster implementation of SERS into cell secretome classification, which can be extended even to laboratories lacking highly specialized facilities.Universidade de Vigo/CISUGAgencia Estatal de Investigación | Ref. PID2019-108787RB-I0

Nanocomposite Scaffolds for Monitoring of Drug Diffusion in Three-Dimensional Cell Environments by Surface-Enhanced Raman Spectroscopy

[EN]Monitoring dynamic processes in complex cellular environments requires the integration of uniformly distributed detectors within such three-dimensional (3D) networks, to an extent that the sensor could provide real-time information on nearby perturbations in a non-invasive manner. In this context, the development of 3D-printed structures that can function as both sensors and cell culture platforms emerges as a promising strategy, not only for mimicking a specific cell niche but also toward identifying its characteristic physicochemical conditions, such as concentration gradients. We present herein a 3D cancer model that incorporates a hydrogel-based scaffold containing gold nanorods. In addition to sustaining cell growth, the printed nanocomposite inks display the ability to uncover drug diffusion profiles by surface-enhanced Raman scattering, with high spatiotemporal resolution. We additionally demonstrate that the acquired information could pave the way to designing novel strategies for drug discovery in cancer therapy, through correlation of drug diffusion with cell death.J.P. acknowledges an FPU fellowship from the Spanish Ministry of Science, Innovation and Universities. L.M.L.-M. acknowledges funding from the European Research Council (Grants ERC AdG 787510, 4DbioSERS) and the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant MDM-2017-0720). A.C. was funded by MICINN (Grant PID2019-108787RB-I00 (FEDER/EU)) and the European Research Council (ERC Consolidator Grant 819242)