Composition-Dependent Cytotoxic and Antibacterial Activity of Biopolymer-Capped Ag/Au Bimetallic Nanoparticles against Melanoma and Multidrug-Resistant Pathogens

Nanostructured silver (Ag) and gold (Au) are widely known to be potent biocidal and cytotoxic agents as well as biocompatible nanomaterials. It has been recently reported that combining both metals in a specific chemical composition causes a significant enhancement in their antibacterial activity against antibiotic-resistant bacterial strains, as well as in their anticancer effects, while preserving cytocompatibility properties. In this work, Ag/Au bimetallic nanoparticles over a complete atomic chemical composition range were prepared at 10 at% through a green, highly reproducible, and simple approach using starch as a unique reducing and capping agent. The noble metal nanosystems were thoroughly characterized by different analytical techniques, including UV-visible and FT-IR spectroscopies, XRD, TEM/EDS, XPS and ICP-MS. Moreover, absorption spectra simulations for representative colloidal Ag/Au-NP samples were conducted using FDTD modelling. The antibacterial properties of the bimetallic nanoparticles were determined against multidrug-resistant Escherichia coli and methicillin-resistant Staphylococcus aureus, showing a clear dose-dependent inhibition even at the lowest concentration tested (5 µg/mL). Cytocompatibility assays showed a medium range of toxicity at low and intermediate concentrations (5 and 10 µg/mL), while triggering an anticancer behavior, even at the lowest concentration tested, in a process involving reactive oxygen species production per the nanoparticle Au:Ag ratio. In this manner, this study provides promising evidence that the presently fabricated Ag/Au-NPs should be further studied for a wide range of antibacterial and anticancer applications.The groups at CSIC and Tecnologico de Monterrey acknowledge the i-Link+2019 program (ref. LINKB20024 “NANOBIO-ROJA”) for financial support. AM acknowledges the Spanish Ministry of Science (RYC2018-024561-I), the regional government of Aragon (E13_20R), the European Union’s Horizon 2020 research and innovation programme (823717– ESTEEM3) and the National Natural Science Foundation of China (NSFC- 21835002).Peer reviewe

Superswelling microneedle arrays for dermal interstitial fluid (prote) omics

The noninvasive sampling of dermal interstitial fluid (ISF) for the monitoring of clinical biomarkers is a greatly appealing area of research. The identification of molecular biomarkers in biological fluids has been accelerated with -omics analyses but remains limited in ISF because of its time-consuming and complex extraction process. Here, the generation of microneedle (MN) patches made of superabsorbent acrylate-based hydrogels for the rapid sampling of dermal ISF is described to explore its proteome. In depth, iterative optimization allows the identification of novel acrylate-based compositions with the required chemical, mechanical, and biocompatibility properties allowing proteomic analysis of the extracted ISF for the first time after sampling with swelling MNs. The generated MN arrays show no cytotoxic effect, successfully cross the stratum corneum, and can collect up to 6 µL of dermal ISF in 10 min in vivo. Proteomics lead to the detection of 176 clinically relevant biomarkers in the collected samples validating the use of ISF as a relevant bodily fluid for disease monitoring and diagnostic. Importantly, it is discovered that extraction fingerprint is strongly dependent on the MNs chemistry, and thus specific biomarkers could be selectively extracted by tuning the composition of the patch, making the system versatile and specific

Starch-mediated synthesis of mono- and bimetallic silver/gold nanoparticles as antimicrobial and anticancer agents

Background and aim: Bimetallic silver/gold nanosystems are expected to significantly improve therapeutic efficacy compared to their monometallic counterparts by maintaining the general biocompatibility of gold nanoparticles (AuNPs) while, at the same time, decreasing the relatively high toxicity of silver nanoparticles (AgNPs) toward healthy human cells. Thus, the aim of this research was to establish a highly reproducible one-pot green synthesis of colloidal AuNPs and bimetallic Ag/Au alloy nanoparticles (NPs; Ag/AuNPs) using starch as reducing and capping agent. Methods: The optical properties, high reproducibility, stability and particle size distribution of the colloidal NPs were analyzed by ultraviolet (UV)–visible spectroscopy, dynamic light scattering (DLS) and ζ-potential. The presence of starch as capping agent was determined by Fourier transform infrared (FT-IR) spectroscopy. The structural properties were studied by X-ray diffraction (XRD). Transmission electron microscopy (TEM) imaging was done to determine the morphology and size of the nanostructures. The chemical composition of the nanomaterials was determined by energy-dispersive X-ray spectroscopy (EDS) and inductively coupled plasma mass spectrometry (ICP-MS) analysis. To further study the biomedical applications of the synthesized nanostructures, antibacterial studies against multidrug-resistant (MDR) Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) were conducted. In addition, the NPs were added to the growth media of human dermal fibroblast (HDF) and human melanoma cells to show their cytocompatibility and cytotoxicity, respectively, over a 3-day experiment. Results: UV–visible spectroscopy confirmed the highly reproducible green synthesis of colloidal AuNPs and Ag/AuNPs. The NPs showed a face-centered cubic crystal structure and an icosahedral shape with mean particle sizes of 28.5 and 9.7 nm for AuNPs and Ag/AuNPs, respectively. The antibacterial studies of the NPs against antibiotic-resistant bacterial strains presented a dose-dependent antimicrobial behavior. Furthermore, the NPs showed cytocompatibility towards HDF, but a dose-dependent anticancer effect was found when human melanoma cells were grown in presence of different NP concentrations for 72 hours. Conclusion: In this study, mono- and bimetallic NPs were synthesized for the first time using a highly reproducible, environmentally friendly, cost-effective and quick method and were successfully characterized and tested for several anti-infection and anticancer biomedical applications

Green synthesis and characterization of gold-based anisotropic nanostructures using bimetallic nanoparticles as seeds

Nanostructured noble metals are of great interest because of their tunable optical and electronic properties. However, the green synthesis of anisotropic nanostructures with a defined geometry by the systematic nanoassembly of particles into specific shape, size, and crystallographic facets still faces major challenges. The present work aimed to establish an environmentally friendly methodology for synthesizing gold-based anisotropic nanostructures using starch-capped bimetallic silver/gold nanoparticles as seeds and hydrogen peroxide as a reducing agent.The authors thank the i-Link+2019 program between CSIC and Tecnologico de Monterrey (ref. LINKB20024 “NANOBIO-ROJA”) for financial support. We thank Marcelo Videa for proofreading the article.Peer reviewe

Eco-friendly synthesis of Te nanostructures with antibacterial and anticancer properties

Trabajo presentado en el 2nd Spanish Conference on Biomedical Applications of Nanomaterials (SBAN), celebrado en Madrid (España) los días 6 y 7 de junio de 2019Bacterial infections and cancer are two of the most significant issues that the current healthcare system should tackle nowadays. Traditional routes for the synthesis of the different compounds, drugs and nanostructures that are developed as potential solutions for those problems usually have several limitations, such as the use of harsh chemicals and production of toxic by-products with limited biocompatibility. In that sense, green chemistry offers a suitable approach, with safe and environmentally friendly manufacturing and minimal use of toxic chemicals. In this work, effective green routes for the synthesis of Te nanostructures are presented, based on hydrothermal or microwave-assisted reactions employing either starch [1], either citric juice (from orange, lemon or lime) [2] as unique reducing and stabilizing agents. The nanostructures were extensively characterized in terms of morphology, surface chemistry and composition, by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Depending on the fabrication parameters, long nanowires, nanorods or cubic shaped nanoparticles were obtained. These Te nanostructures showed antibacterial activity against both Gram-negative and -positive bacteria in a range of concentrations from 5 to 50 μg mL−1. Cytotoxicity studies were accomplished, showing a dose-dependent anticancer effect towards human melanoma cells for concentrations up to 100 μg mL−1, remaining cytocompatible towards human healthy fibroblast cells at concentrations below 50 μg mL−1 for the majority of Te morphologies. These antibacterial and anticancer properties were correlated with the production of reactive oxygen species (ROS). This study suggests that green chemistry approaches for producing Te nanostructures may not only reduce adverse environmental effects resulting from traditional synthetic chemistry methods, but can be effective in interesting health care applications

Citric juice-mediated synthesis of tellurium nanoparticles with antimicrobial and anticancer properties

Bacterial infections and cancer are two of the most significant concerns that the current healthcare system should tackle nowadays. Green nanotechnology is presented as a feasible solution that is able to produce materials with significant anticancer and antibacterial activity, while overcoming the main limitations of traditional synthesis. In the present work, orange, lemon and lime extracts were used as both reducing and capping agents for the green synthesis of tellurium nanoparticles (TeNPs) using a microwave-assisted reaction. TeNPs showed a uniform size distribution, and rod- and cubic-shapes, and were extensively characterized in terms of morphology, structure and composition using TEM, SEM, XPS, XRD, FTIR and EDX analysis. TeNPs showed an important antibacterial activity against both Gram-negative and -positive bacteria in a range concentrations from 5 to 50 μg mL−1 over a 24-hour time period. Besides, nanoparticles showed an anticancer effect towards human melanoma cells over 48 hours at concentrations up to 50 μg mL−1. Moreover, the Te nanostructures showed no significant cytotoxic effect towards human dermal fibroblast at concentrations up to 50 μg mL−1. Therefore, we present an environmentally-friendly and cost-effective synthesis of TeNPs using only fruit juices and showing enhanced and desirable biomedical properties towards both infectious diseases and cancer.This work was supported by the Chemical Engineering Department at Northeastern University. Funding from MINECO (MAT2014-59772-C2-1-P and MAT2014-59772-C2-2-P) and the European Union [grant number ERC-2013-SyG 610256 NANOCOSMOS] is acknowledged. We also acknowledge the service from the MiNa Laboratory at IMN funded by CM (S2013/ICE2822), MINECO (CSIC13-4E-1794) and the EU (FEDER, FSE).Peer reviewe

Eco-friendly synthesis of Tellurium nanoparticles and synergic antibacterial coatings in combination with titanium nanocolumns

Trabajo presentado al European Congress and Exhibition on Advanced Materials and Processes (EUROMAT), celebrado en Estocolmo (Suecia) del 1 al 5 de septiembre de 2019.Introduction/Purpose: Antimicrobial resistance to antibiotics is one of the main concerns that the healthcare system should face nowadays. Current antibiotic treatments are becoming ineffective or have plenty of drawbacks. Therefore, new alternatives are needed. Traditional synthesis of nanomaterials is subjected to several disadvantages, such as the production of toxic-by-products and harsh conditions. Ecofriendly methods in nanotechnology can be a suitable answer, allowing for the generation of nanostructures in a cost-effective and environmentally-friendly approach. Methods: Tellurium, a rare metalloid with the largely unknown biological role, is presented as a suitable antibacterial agent in its nanoscale form. Tellurium nanostructures of different morphologies were prepared using two different approaches: an environmentally-friendly hydrothermal and microwave-assisted methods using polyvinylpyrrolidone (PVP) and citric extracts as unique reducing and capping agents, respectively. The nanostructures were extensively characterized in terms of morphology, surface chemistry, and composition, as well as tested in antimicrobial assays towards antibiotic-resistant phenotypes as efficient biomedical agents. Results: The different Te nanostructures showed a dose-dependent antimicrobial activity, with low cytotoxicity towards human cells. Then, the nanoparticles were used as a coating in the surface of nanocolumnar titanium materials for implantation. The synergetic structures were tested for their antimicrobial activity towards bacteria, showing an enhancement of the bactericidal effect compared to the plain titanium surfaces, with low cytotoxicity toward human osteoblasts cells. Conclusions: Therefore, a sustainable method vas employed for generation of Te nanostructures that are suitable as antibacterial agents and additives for the successful enhancement of antibacterial coatings for implantation devices. The synthesis was able to overcome the main limitations of traditional chemistry and showed efficient for generation of biomedical agents

XIII Jornada de Investigación 2022

Los desafíos en las dinámicas económicas, sociales, políticas y psicológicas han puesto de relieve la importancia de involucrar en la enseñanza universitaria actividades que conecten a los estudiantes con las realidades del contexto en el que se desarrollan; simultáneamente, hoy más que nunca se hace evidente que la ciencia, la tecnología y la innovación (CTI) son cruciales para atender los retos sociales, ambientales y económicos de las sociedades actuales. En este contexto, la Jornada de Investigación de la Universidad Católica de Colombia es quizás uno de los espacios institucionales más emblemáticos en el que se visibilizan las actividades en CTI de estudiantes, jóvenes investigadores y profesores, que buscan contribuir a la solución de problemáticas relevantes del entorno. En esta oportunidad, aproximadamente 177 autores y más de 250 espectadores se dieron cita en un escenario virtual que permitió el intercambio de saberes y conocimientos en torno a muchos temas con un lenguaje común: el bienestar de la humanidad y la respuesta efectiva a los retos que tenemos como comunidad. Esta cuarta versión de las Memorias compila las ponencias presentadas en la XIII Jornada de Investigación de 2022, enmarcadas en los tres ejes temáticos de investigación que tiene la Universidad Católica de Colombia: i) Derecho, Cultura y Sociedad, ii) Desarrollo Humano y Sostenible, y iii) Gestión de la Tecnología al Servicio de la Sociedad. Desde la Dirección Central de Investigaciones nos encontramos profundamente agradecidos con todos y cada uno de los participantes, y nos sentimos aún más orgullosos por la calidad de los trabajos presentados. Sea esta la oportunidad para hacer extensiva una felicitación a los autores y a las diferentes Unidades Académicas que, con su compromiso e invaluable labor, permitieron que este evento se desarrollara con éxito.Persona, hospitalidad y construcción de comunidad desde la fraternidad. José Martí: acerca de la libertad en la condición humana. Moda, imagen y alimentación: una tríada para el bien y para el mal. Lecciones de la pandemia de covid-19: conflictos entre la protección jurídica de las patentes farmacéuticas y el interés general de la salud pública. Psicología y sexualidad: propuesta para la formación de psicólogos colombianos. Estrategias para el desarrollo de herramientas que fomentan el aprendizaje para el reconocimiento y la apropiación del patrimonio cultural. Análisis descriptivo de relatos honestos y deshonestos por medio del sistema de evaluación global. El uso de la herramienta LIWC para el estudio de relatos altruistas y prosociales. ¿De qué manera influyen las redes sociales como medio de información en campañas políticas?. Sistema de Seguridad Social en Colombia: una crisis deficitaria que se refuerza con el tiempo. Turismo sexual en menores de edad: problemática endémica en el territorio colombiano. Transgresión de los derechos humanos en relación con los asesinatos de líderes sociales en el Estado colombiano. El nuevo escenario para la procedencia de la eutanasia en Colombia: una mirada desde los derechos humanos. Protección de los derechos de la infancia frente a los grupos al margen de la ley. El derecho a un nivel de vida adecuado: un enfoque hacia el desplazamiento forzado de los pueblos indígenas. Tráfico de órganos humanos: delito transnacional que vulnera los derechos humanos y su regulación en el marco jurídico colombiano. Transgresión de los derechos a la vida y la libertad en el sistema penitenciario como consecuencia de la violencia social. Acceso a la justicia colombiana en tiempos de SARS-CoV-2. Prioridades para la administración de justicia penal en Colombia: ¿balanceando espectáculo e indicadores de eficacia? Desarrollo de competencias para la investigación en neuropsicología: experiencia del semillero experimental. La dificultad al ingreso de los centros geriátricos. Principio de realidad sobre la formalidad constitucional en contrato verbal laboral en un satélite del Consultorio Jurídico de la Universidad Católica de Colombia. La pena de muerte en colisión con los derechos fundamentales. Maternidad subrogada: objetificación y vulneración de los derechos de la mujer. Una dieta inconsciente hacia el vegetarianismo. Sistema de evaluación del bienestar gerontológico para un diseño arquitectónico sostenible. Caso de estudio: hogar de paso San Francisco de Asís, Villavicencio, Meta. Revisión sistemática interacción líder-colaborador: futuras investigaciones. Análisis conceptual del talento académico desde los modelos teóricos que lo sustentan. Identificación de potenciales factores de riesgo suicida: una mirada contextual. La regulación emocional en tiempos de coronavirus. GEES: Guía de Evaluación de Edificaciones Sostenibles, vivienda de interés social, clima cálido húmedo. Estructura proyectual y sostenible para el diseño y desarrollo de un modelo de vivienda de madera en San Andrés y Providencia, Colombia. Innovación social para la gestión territorial. Construcción de material didáctico para el entrenamiento en habilidades de regulación emocional e interpersonales dirigidas a poblaciones expuestas a situaciones de violencia política. Alternativas sostenibles de modelos de desarrollo industrial. La ruralidad dentro de los procesos del desarrollo local en Usme. Se ha dejado de dibujar arquitectura con las manos. Calidad de vida, bienestar y felicidad en el trabajo: una revisión sistemática de la literatura científica, 2011-2021. Autonomía, autorregulación y educación moral: reflexiones desde la psicología del desarrollo moral. Características de los niños, niñas y adolescentes expuestos a contextos de conflicto armado en Colombia. Revisión bibliométrica de artículos sobre la crianza en niños, niñas y adolescentes colombianos. Narrativas sociales en el proceso de cualificación de lo público La habitación exterior como extensión de la vivienda. Utilización de nanopartículas magnéticas Fe3O4 y ozono para la degradación/eliminación de azul de metileno en agua residual textil. Estudio paramétrico de un modelo numérico Fem de un ensayo CBR. ¿Cómo construir identidad de manera incluyente a partir del reconocimiento de patrimonio cultural construido?. Veracidad de los resultados del ensayo de penetración dinámica de CONO(PDC). Análisis de texto a partir del procesamiento de lenguaje natural para identificar sintomatología depresiva en redes sociales. Análisis de texto para la detección de depresión en comentarios de usuarios de la red social Instagram. Diseño y desarrollo de un videojuego para evaluar la interacción de las redes atencionales en la sintomatología depresiva. Herramienta tecnológica para el apoyo en la detección de sintomatología ansiosa en jóvenes. Optimización del despliegue de aplicaciones web a partir de computación en nube sin servidor. Prototipo alfa de un videojuego serio para el apoyo en la detección de sintomatología depresiva en adultos jóvenes. La importancia de la visualización de datos en la era del Big Data y sus herramientas. Prototipo de sensor para el registro electroencefalográfico. Prototipo de un algoritmo basado en inteligencia artificial para el apoyo a especialistas en el diagnóstico del Alzheimer. Evaluación posocupacional del confort térmico en la vivienda social: análisis de una revisión sistemática prisma desde el diseño resiliente. Inteligencia artificial, problema u oportunidad para el Derecho. Impacto en el empleo en relación con las TIC y la inteligencia artificial. Neuroprivacidad. El test de asociación implícita, un paradigma que permite abordar nuestras actitudes inconscientes. ¿Cuál es el límite del uso de las tecnologías frente al derecho de información y de la libre expresión?. Tendencias de fijación de precios basados en el valor: un análisis desde la minería de datos. Recorrido virtual de la Universidad Católica de Colombia Sede Claustro para la inducción de estudiantes y docentes. Introducción a la bioarquitectura del paisaje, cartilla Paisaje, ambiente y tecnología. Descripción plan piloto (Choachí). Caracterización de las habilidades específicas para el reconocimiento del patrimonio cultural – Borde urbano sur oriental de Bogotá. Videojuego para estimular la memoria episódica en pacientes con deterioro cognitivo leve: validación de contenido. CONCLUSIONESTercera edició