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La nanotecnología y la nanociencia constituyen áreas científicas interrelacionadas, en constante expansión y de gran relevancia en la investigación contemporánea, que se centran en el estudio, manipulación y comprensión de la materia a escala nanométrica. La nanociencia tiene como objetivo fundamental proporcionar un conocimiento profundo sobre las propiedades inherentes a escala nanométrica, mientras que la nanotecnología capitaliza dicho conocimiento para desarrollar aplicaciones y tecnologías de vanguardia. En conjunto, la nanociencia y la nanotecnología han captado la atención de la comunidad científica, ofreciendo un futuro prometedor y un potencial impacto en múltiples áreas con relevancia socioeconómica en la actualidad como la energía o la sostenibilidad. Tal y como se detalla en el Capítulo 1, su continuo avance ha permitido el desarrollo de nuevos tipos de nanopartículas metálicas (NPs), constituidas por uno o más metales, con morfologías y tamaños bien definidos, las cuales han despertado un gran interés debido a sus propiedades ópticas únicas que les confieren un gran potencial en diversas aplicaciones tecnológicas como sensores, catálisis, biomedicina, liberación de fármacos y optoelectrónica. Estas estructuras metálicas exhiben propiedades plasmónicas diferenciadoras como consecuencia de su interacción con la luz, que dependen fundamentalmente de su composición, tamaño y forma..., Nanotechnology and nanoscience are interconnected scientific fields that are constantly expanding and of great relevance in contemporary research. They focus on the study, manipulation, and understanding of matter at the nanoscale. Nanoscience essentially aims to provide in-depth knowledge of properties inherent at the nanoscale, while nanotechnology capitalizes on this knowledge to develop cutting-edge applications and technologies. Together, nanoscience and nanotechnology have captured the attention of the scientific community, offering a promising future and a potential impact in multiple areas of current socio-economic relevance, such as energy or sustainability. As detailed in Chapter 1, their continuous advance has led to the development of new types of metal nanoparticles (NPs), consisting of one or more metals, with well-defined morphologies and sizes, which have attracted great interest due to their unique optical properties that give them great potential in various technological applications such as sensors, catalysis, biomedicine, drug delivery and optoelectronics. These metallic structures exhibit distinct plasmonic properties because of their interaction with light, which depend primarily on their composition, size, and shape...

Gold nanorods are the most commonly used nanoparticles in photothermal therapy for cancer treatment due to their high efficiency in converting light into heat. This study aimed to investigate the efficacy of gold nanorods of different sizes (large and small) in eliminating two types of cancer cell: melanoma and glioblastoma cells. After establishing the optimal concentration of nanoparticles and determining the appropriate time and power of laser irradiation, photothermal therapy was applied to melanoma and glioblastoma cells, resulting in the highly efficient elimination of both cell types. The efficiency of the PTT was evaluated using several methods, including biochemical analysis, fluorescence microscopy, and flow cytometry. The dehydrogenase activity, as well as calcein-propidium iodide and Annexin V staining, were employed to determine the cell viability and the type of cell death triggered by the PTT. The melanoma cells exhibited greater resistance to photothermal therapy, but this resistance was overcome by irradiating cells at physiological temperatures. Our findings revealed that the predominant cell-death pathway activated by the photothermal therapy mediated by gold nanorods was apoptosis. This is advantageous as the presence of apoptotic cells can stimulate antitumoral immunity in vivo. Considering the high efficacy of these gold nanorods in photothermal therapy, large nanoparticles could be useful for biofunctionalization purposes. Large nanorods offer a greater surface area for attaching biomolecules, thereby promoting high sensitivity and specificity in recognizing target cancer cells. Additionally, large nanoparticles could also be beneficial for theranostic applications, involving both therapy and diagnosis, due to their superior detection sensitivity., Ministerio de Ciencia, Innovación y Universidades (España), Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub, Descuento UCM

Metal nanocrystals (NCs) display unique physicochemical features that are highly dependent on the nanoparticle dimensions, anisotropy, structure, and composition. The development of synthesis methodologies that allow us to tune such parameters finely emerges crucial for the application of metal NCs in catalysis, optical materials, or biomedicine. Here, we describe a synthetic methodology to fabricate hollow multimetallic heterostructures using a combination of seed-mediated growth routes and femtosecond pulsed laser irradiation. The envisaged methodology relies on the co-reduction of Ag and Pd ions on gold nanorods (Au NRs) to form Au@PdAg core–shell nanostructures containing small cavities at the Au-PdAg interface. The excitation of Au@PdAg NRs with low fluence femtosecond pulses was employed to induce the coalescence and growth of large cavities, forming multihollow anisotropic Au@PdAg nanostructures. Moreover, single-hollow alloy AuPdAg could be achieved in high yield by increasing the irradiation energy. Advanced electron microscopy techniques, energy-dispersive X-ray spectroscopy (EDX) tomography, X-ray absorption near edge structure (XANES) and FDTD (finite differences in the time domain) simulationsallowed us to characterize the morphology, structure, and elemental distribution of the irradiated NCs in detail. The ability of the reported synthesis route to fabricate multimetallic NCs with unprecedented hollow nanostructures brings attractive prospects for the fabrication of tailored high-entropy alloy nanoparticles., Ministerio de Ciencia e Innovación (España), Comunidad de Madrid, European Commission, Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, inpress

The search for efficient plasmonic photothermal therapies using nonharmful pulse laser irradiation at the near-infrared (NIR) is fundamental for biomedical cancer research. Therefore, the development of novel assembled plasmonic gold nanostructures with the aim of reducing the applied laser power density to a minimum through hot-spot-mediated cell photothermolysis is an ongoing challenge. We demonstrate that gold nanorods (Au NRs) functionalized at their tips with a pH-sensitive ligand assemble into oligomers within cell lysosomes through hydrogen-bonding attractive interactions. The unique intracellular features of the plasmonic oligomers allow us to significantly reduce the femtosecond laser power density and Au NR dose while still achieving excellent cell killing rates. The formation of gold tip-to-tip oligomers with longitudinal localized surface plasmon resonance bands at the NIR, obtained from low-aspect-ratio Au NRs close in resonance with 800 nm Ti:sapphire 90 fs laser pulses, was found to be the key parameter for realizing the enhanced plasmonic photothermal therapy., MAT2014-59678-R, CTQ2012-37404-C02-01, S2013/MIT-2807, ERC-StG-2011- 278860, ERC-StG-2013-338133, Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub

Este proyecto plantea la herramienta EChemTest como mecanismo de evaluación de la Calidad de un Grado relacionado con la Química. También presenta la oportunidad de evaluar cómo ha influido la docencia online en la adquisición de conocimientos, comparando con cursos anteriores.

Gene therapy is a very promising branch of biomedicine that aims to treat inherited or acquired diseases (such as cancer, cardiovascular, neurological and inflammatory diseases) at molecular level. The purpose is to restore correct cell function using nucleic acids (NAs) as therapeutic agents. Depending on the NAs inserted, there are different mechanisms of action. For instance, plasmids DNA (pDNAs) use the patient's biological machinery to replace the defective gene and express the healthy exogenous gene of interest. Other NAs, such as small interfering RNAs (siRNAs), prevent the synthesis of the pathogenic protein by knockdown the corresponding genes. In most cases, NAs require a carrier agent, known as vector, for their internalization into the target cells. Viruses were the source of inspiration during the early stages of gene therapy for the insertion of NAs into cells. Nowadays, viral vectors are still in use due to their high efficiency; however, the undesirable adverse effects associated with their use are forcing the search for alternatives. Among the different synthetic options for non-viral vectors, polymeric and colloidal systems stand out. Within colloidal systems, cationic lipids (CLs) are perhaps the most studied group due to their ability to interact electrostatically with anionic NAs, and spontaneously self-organize in aqueous solution forming structures similar to that of the cell membrane. The resulting complex between the CLs and NAs, well-known as lipoplex, must transport the NAs into cells and release them into the cytoplam without causing damage. The efficiency of this process will depend on the vector’s capacity to overcome the known biological barriers during its physiological journey..., La terapia génica es una rama muy prometedora de la biomedicina que tiene como objetivo tratar enfermedades heredadas o adquiridas (como el cáncer o las enfermedades cardiovasculares, neurológicas e inflamatorias) a nivel molecular. En ella se utilizan ácidos nucleicos (NAs) como agentes terapéuticos para tratar de restablecer el correcto funcionamiento celular. Según los NAs insertados, existen distintos mecanismos de acción. Por ejemplo, los plásmidos de DNA (pDNAs) utilizan la maquinaria biológica del paciente para reemplazar el gen defectuoso y expresar el gen exógeno sano de interés. Otros NAs, como los pequeños RNAs de interferencia (siRNAs), bloquean la síntesis de la proteína defectuosa silenciando los genes específicos correspondientes. En la mayoría de los casos, los NAs necesitan un agente transportador, conocido como vector, para su internalización en las células. Los virus fueron la fuente de inspiración para insertar los NAs en las células durante las primeras etapas de la terapia génica. Aunque actualmente aún son utilizados como vectores dada su alta eficacia, los indeseados efectos adversos que provocan obligan a buscar otras alternativas. Entre las distintas opciones sintéticas de vectores no virales destacan los sistemas poliméricos y los coloidales. Dentro de este último grupo, los lípidos catiónicos (CLs) son quizás los más estudiados por su capacidad para interaccionar electrostáticamente con los NAs aniónicos y auto-organizarse espontáneamente en medio acuoso formando estructuras similares a las de la membrana celular. El complejo resultante, conocido como lipoplejo, debe transportar el material genético hasta el interior celular y liberarlo en el citoplasma sin causar daños. La eficacia de este proceso dependerá de la capacidad que muestre el vector durante su recorrido fisiológico para superar ciertas barreras biológicas...

Ample evidence exists on the role of interleukin-12 (IL-12) in the response against many pathogens, as well as on its remarkable antitumor properties. However, the unexpected toxicity and disappointing results in some clinical trials are prompting the design of new strategies and/or vectors for IL-12 delivery. This study was conceived to further endorse the use of gemini cationic lipids (GCLs) in combination with zwitterionic helper lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphatidyl ethanol amine) as nanovectors for the insertion of plasmid DNA encoding for IL-12 (pCMV-IL12) into cells. Optimal GCL formulations previously reported by us were selected for IL-12-based biophysical experiments. In vitro studies demonstrated efficient pCMV-IL12 transfection by GCLs with comparable or superior cytokine levels than those obtained with commercial control Lipofectamine2000*. Furthermore, the nanovectors did not present significant toxicity, showing high cell viability values. The proteins adsorbed on the nanovector surface were found to be mostly lipoproteins and serum albumin, which are both beneficial to increase the blood circulation time. These outstanding results are accompanied by an initial physicochemical characterization to confirm DNA compaction and protection by the lipid mixture. Although further studies would be necessary, the present GCLs exhibit promising characteristics as candidates for pCMV-IL12 transfection in future in vivo applications., Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Insituto de Salud Carlos III (ISCIII)/FEDER, Universidad Complutense de Madrid, Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub

Gene therapy is a very promising branch of biomedicine that aims to treat inherited or acquired diseases (such as cancer, cardiovascular, neurological and inflammatory diseases) at molecular level. The purpose is to restore correct cell function using nucleic acids (NAs) as therapeutic agents. Depending on the NAs inserted, there are different mechanisms of action. For instance, plasmids DNA (pDNAs) use the patient's biological machinery to replace the defective gene and express the healthy exogenous gene of interest. Other NAs, such as small interfering RNAs (siRNAs), prevent the synthesis of the pathogenic protein by knockdown the corresponding genes. In most cases, NAs require a carrier agent, known as vector, for their internalization into the target cells. Viruses were the source of inspiration during the early stages of gene therapy for the insertion of NAs into cells. Nowadays, viral vectors are still in use due to their high efficiency; however, the undesirable adverse effects associated with their use are forcing the search for alternatives. Among the different synthetic options for non-viral vectors, polymeric and colloidal systems stand out. Within colloidal systems, cationic lipids (CLs) are perhaps the most studied group due to their ability to interact electrostatically with anionic NAs, and spontaneously self-organize in aqueous solution forming structures similar to that of the cell membrane. The resulting complex between the CLs and NAs, well-known as lipoplex, must transport the NAs into cells and release them into the cytoplam without causing damage. The efficiency of this process will depend on the vector’s capacity to overcome the known biological barriers during its physiological journey...

Efficient plasmonic photothermal therapies (PPTTs) using non-harmful pulse laser irradiation at the near-infrared (NIR) are a highly sought goal in nanomedicine. These therapies rely on the use of plasmonic nanostructures to kill cancer cells while minimizing the applied laser power density. Cancer cells have an unsettled capacity to uptake, retain, release, and re-uptake gold nanoparticles, thus offering enormous versatility for research. In this work, we have studied such cell capabilities for nanoparticle trafficking and its impact on the effect of photothermal treatments. As our model system, we chose uveal (eye) melanoma cells, since laser-assisted eye surgery is routinely used to treat glaucoma and cataracts, or vision correction in refractive surgery. As nanostructure, we selected gold nanostars (Au NSs) due to their high photothermal efficiency at the near-infrared (NIR) region of the electromagnetic spectrum. We first investigated the photothermal effect on the basis of the dilution of Au NSs induced by cell division. Using this approach, we obtained high PPTT efficiency after several cell division cycles at an initial low Au NS concentration (pM regime). Subsequently, we evaluated the photothermal effect on account of cell division upon mixing Au NS-loaded and non-loaded cells. Upon such mixing, we observed trafficking of Au NSs between loaded and non-loaded cells, thus achieving effective PPTT after several division cycles under low irradiation conditions (below the maximum permissible exposure threshold of skin). Our study reveals the ability of uveal melanoma cells to release and re-uptake Au NSs that maintain their plasmonic photothermal properties throughout several cell division cycles and re-uptake. This approach may be readily extrapolated to real tissue and even to treat in situ the eye tumor itself. We believe that our method can potentially be used as co-therapy to disperse plasmonic gold nanostructures across affected tissues, thus increasing t, Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Depto. de Química Física, Fac. de Ciencias Químicas, TRUE, pub

I.amAble ha ofrecido a estudiantes universitarios de física, química, veterinaria, biología y educación la oportunidad de complementar su formación mediante el diseño, la realización y la evaluación de talleres científicos que faciliten la inclusión de personas con diversidad cognitiva. Los talleres han sido diseñados por el alumnado universitario de ciencias y perfilados por estudiantes de educación para ser llevados a cabo por alumnado preuniversitario en parejas, de forma que un miembro pertenezca a un centro de secundaria ordinario y el otro miembro a un centro de educación especial. Aquellos talleres que se han considerado más adecuados por su adaptabilidad se han llevado a la práctica guiados por estudiantes de ciencias y de educación. Los miembros del proyecto, que incluyen representantes de todos los estamentos universitarios, han supervisado todas las tareas descritas anteriormente. Además de los miembros de la Universidad Complutense, también figuran personas voluntarias de otras instituciones científicas y educativas. El alumnado universitario ha tenido la posibilidad, no sólo de asentar y profundizar algunos contenidos científicos o poner en práctica algunas de las enseñanzas adquiridas, sino también de desarrollar su empatía, su capacidad de comunicar e improvisar y de adaptarse a un público heterogéneo. Ello ha mejorado sus perspectivas laborales, especialmente dentro de la educación formal e informal (animación sociocultural, museos científicos...). Además, han contribuido a facilitar la inclusión educativa de las personas con diversidad funcional y a mejorar la cultura científica de la sociedad. Con este proyecto, inspirado en la metodología Aprendizaje-Servicio (ApS), se ha pretendido también mejorar la accesibilidad a las experiencias y contenidos científicos y facilitar la inclusión educativa de las personas con diversidad funcional, especialmente diversidad cognitiva o intelectual. En la primera edición de I.amAble (2016-17) se hizo hincapié en e

Colloidal anisotropic gold nanocrystals play a central role in the field of plasmonics owing to their tunable optical activity across a wide spectral range. However, achieving sufficient optical quality for practical implementation requires advanced synthetic protocols yielding gold nanocrystals with the desired morphology and plasmonic properties. This Minireview focuses on a fundamental step during the growth of anisotropic nanocrystals, namely symmetry breaking. In connection with thermodynamic and kinetic control of nanocrystal growth, we discuss the complex interplay between the role of seed morphology and that of surfactants, shape‐directing additives and reducing agents. We revisit some iconic syntheses of anisotropic gold nanoparticles, including nanorods, nanotriangles, and nanobipyramids. Finally, we analyze the use of co‐surfactants as an emerging strategy to disconnect the symmetry breaking event from the anisotropic growth process, overcoming current limitations in the synthesis of anisotropic gold nanocrystals.