Search

In this work we present the development of an electrochemiluminescence aptasensor based on electrografting molybdenum disulphide nanosheets functionalized with diazonium salt (MoS2-N2+) upon screen-printed electrodes of graphene (SPEs GPH) for viral proteins detection. In brief, this aptasensor consists of SPEs GPH electrografted with MoS2-N2+ and modified with a thiolated aptamer, which can specifically recognize the target protein analyte. In this case, we have used SARS-CoV-2 spike protein as model protein. Electrochemiluminescence detection was performed by using the [Ru(bpy)3]2+/TPRA (tripropylamine) system, which allows the specific detection of the SARS-CoV-2 spike protein easily and rapidly with a detection limit of 9.74 fg/mL and a linear range from 32.5 fg/mL to 50.0 pg/mL. Moreover, the applicability of the aptasensor has been confirmed by the detection of the protein directly in human saliva samples. Comparing our device with a traditional saliva antigen test, our aptasensor can detect the spike protein even when the saliva antigen test gives a negative result.

This work focuses on the development of an electrochemiluminescent nanostructured DNA biosensor for SARS-CoV-2 detection. Gold nanomaterials (AuNMs), specifically, a mixture of gold nanotriangles (AuNTs) and gold nanoparticles (AuNPs), are used to modified disposable electrodes that serve as an improved nanostructured electrochemiluminescent platform for DNA detection. Carbon nanodots (CDs), prepared by green chemistry, are used as coreactants agents in the [Ru(bpy)3]2+ anodic electrochemiluminescence (ECL) and the hybridization is detected by changes in the ECL signal of [Ru(bpy)3]2+/CDs in combination with AuNMs nanostructures. The biosensor is shown to detect a DNA sequence corresponding to SARS-CoV-2 with a detection limit of 514 aM.

In the current socio-sanitary scenario that we are facing as a result of the SARS-CoV-2 Pandemic, there have been many activities that have been reduced and even suspended due to long periods of social isolation and care measures to avoid contagion. In this sense, many people have stopped receiving their treatments with the same regularity or under the same circumstances, including children with Neurodevelopmental Disorders. This is how parental interventions correspond to programs where parents or primary caregivers are trained to carry out therapeutic actions with the child and whose objective may be aimed at promoting multiple skills. The objective of this systematic review was to determine the effect of these interventions to promote language and communication in children diagnosed with Neurodevelopmental Disorders between 2 and 5 years of age. A systematic search was carried out in the ERIC, MEDLINE and PubMed databases including publications between January 2010 and March 2022. Of the 9885 initial references, and after the screening and eligibility stages, 5 primary sources met the selection criteria. The results indicate that parental interventions for communication skills would be effective, and the effects would even be maintained in follow-up measures. Regarding language skills, the results across studies are contradictory. On the other hand, none of the studies reported adverse effects for children. Regarding beneficial or adverse effects for parents or primary caregivers, none of the included studies reported associated measures., En el actual escenario sociosanitario enfrentado a raíz de la pandemia por SARS-CoV-2, múltiples actividades se han visto mermadas, e incluso, suspendidas por los largos periodos de aislamiento social y las medidas de cuidado para evitar contagios. En este sentido, muchas personas han dejado de recibir con la misma regularidad, o bajo las mismas circunstancias, sus tratamientos, incluyendo a niños con Trastornos del Neurodesarrollo (TND). Es así como surgen las intervenciones Parentales. Estas son programas donde los padres o cuidadores primarios son entrenados para llevar a cabo acciones terapéuticas con el niño y cuyo objetivo puede estar orientado a promover múltiples habilidades. El objetivo de la presente revisión sistemática fue determinar el efecto de estas intervenciones para promover el lenguaje y la comunicación en niños con diagnóstico de TND de entre 2 y 5 años. Se realizó una búsqueda sistemática en las bases de datos ERIC, MEDLINE y PubMed, considerando publicaciones de entre enero del 2010 y marzo de 2022. De las 9885 referencias iniciales, y posterior a las etapas de tamizaje y elegibilidad, 5 fuentes primarias cumplieron con los criterios de selección. Los resultados indican que las intervenciones parentales para habilidades de comunicación serían efectivas e incluso se mantendrían los efectos en medidas de seguimiento. En cuanto a las habilidades de lenguaje, los resultados a través de los estudios son contradictorios. Por otra parte, ninguno de los estudios reporta efectos adversos para los niños. En cuanto a efectos beneficios o adversos para padres o cuidadores primarios, ninguno de los estudios incluidos reporta medidas asociadas.

An advanced, cost-effective, and portable DNA biosensor capable of detecting multiple bacteria simultaneously has been developed. The biosensor comprises a fast and inexpensive potentiostat that controls the applied potential to a screen-printed electrochemical array platform functionalized with MoS2 flakes and bacterial DNA probes. The current response obtained by à la carte thionine functionalized carbon nanodots (Ty-CDs) is monitored as an electrochemical indicator of the hybridization event. The design of the potentiostat prioritizes achieving an optimal signal-to-noise ratio and incorporates a user-friendly interface compatible with various devices, including computers, mobile phones, and tablets. The device is compact, lightweight, and manufactured at a low cost. The key components of the potentiostat include a data acquisition board capable of analyzing multiple samples simultaneously and a controller board. The results of this study confirm the ability of the multiplex portable biosensor to successfully detect specific bacterial DNA sequences, demonstrating its reliability and superior performance compared with a traditional, more complex, and laboratory-oriented potentiostat.

In this work, we present the combination of two different types of nanomaterials, 2D molybdenum disulfide nanosheets (MoS2-NS) and zero-dimensional carbon nanodots (CDs), for the development of a new electrochemiluminescence (ECL) platform for the early detection and quantification of the biomarker human epidermal growth factor receptor 2 (HER2), whose overexpression is associated with breast cancer. MoS2-NS are used as an immobilization platform for the thiolated aptamer, which can recognize the HER2 epitope peptide with high affinity, and CDs act as coreactants of the anodic oxidation of the luminophore [Ru(bpy)3]2+. The HER2 biomarker is detected by changes in the ECL signal of the [Ru(bpy)3]2+/CD system, with a low detection limit of 1.84 fg/mL and a wide linear range. The proposed method has been successfully applied to detect the HER2 biomarker in human serum samples.

Heterogeneous photocatalysis has garnered extensive attention because it involves the conversion of photon energy into chemical energy to address many technologies of societal importance, such as solar fuels or hydrogen production. Advances in nanotechnology have improved the ability to develop and specifically tailor the properties of photocatalytic materials. In particular, metal nanoparticles can increase the charge separation efficiency for photocatalytic reactions, thus enlarging the production. Here we present a study of single gold nanoparticles on the surface of TiO2 during illumination with light of band gap energy to study charge trapping, and transfer to the nanoparticle. We used a novel characterization technique, photoassisted Kelvin probe force microscopy (PA-KPFM), to study the process at individual Au NP level, in different environments. We found that the photoinduced electron transfer from TiO2 to the Au NP increases logarithmically with light intensity due to the combined contribution of electron¿hole pair generation in the space charge region in the TiO2¿air interface and in the metal¿semiconductor junction. Our measurements on single particles provide direct evidence for electron trapping that hinders electron¿hole recombination, a key factor in the enhancement of photo(electro)catalytic performance [1].

We studied the effect of gold nanoparticles (Au NPs) deposited on TiO2 on charge generation and trapping during illumination with photons of energy larger than the substrate band gap. We used a novel characterization technique, photoassisted Kelvin probe force microscopy (PA-KPFM), to study the process at the single Au NP level. We found that the photoinduced electron transfer from TiO2 to the Au NP increases logarithmically with light intensity due to the combined contribution of electron¿hole pair generation in the space charge region in the TiO2¿air interface and in the metal¿semiconductor junction. Our measurements on single particles provide direct evidence for electron trapping that hinders electron¿hole recombination, a key factor in the enhancement of photo(electro)catalytic performance [1].

In this work we present a powerful, affordable, and portable biosensor to develop Point of care (POC) SARS-CoV-2 virus detection. It is constructed from a fast, low cost, portable and electronically automatized potentiostat that controls the potential applied to a disposable screen-printed electrochemical platform and the current response. The potentiostat was designed to get the best signal-to-noise ratio, a very simple user interface offering the possibility to be used by any device (computer, mobile phone or tablet), to have a small and portable size, and a cheap manufacturing cost. Furthermore, the device includes as main components, a data acquisition board, a controller board and a hybridization chamber with a final size of 10 × 8 × 4 cm. The device has been tested by detecting specific SARS-CoV-2 virus sequences, reaching a detection limit of 22.1 fM. Results agree well with those obtained using a conventional potentiostat, which validate the device and pave the way to the development of POC biosensors. In this sense, the device has finally applied to directly detect the presence of the virus in nasopharyngeal samples of COVID-19 patients and results confirm its utility for the rapid detection infected samples avoiding any amplification process.

The development of DNA-sensing platforms based on new synthetized Methylene Blue functionalized carbon nanodots combined with different shape gold nanostructures (AuNs), as a new pathway to develop a selective and sensitive methodology for SARS-CoV-2 detection is presented. A mixture of gold nanoparticles and gold nanotriangles have been synthetized to modify disposable electrodes that act as an enhanced nanostructured electrochemical surface for DNA probe immobilization. On the other hand, modified carbon nanodots prepared a la carte to contain Methylene Blue (MB-CDs) are used as electrochemical indicators of the hybridization event. These MB-CDs, due to their structure, are able to interact differently with double and single-stranded DNA molecules. Based on this strategy, target sequences of the SARS-CoV-2 virus have been detected in a straightforward way and rapidly with a detection limit of 2.00 aM. Moreover, this platform allows the detection of the SARS-CoV-2 sequence in the presence of other viruses, and also a single nucleotide polymorphism (SNPs). The developed approach has been tested directly on RNA obtained from nasopharyngeal samples from COVID-19 patients, avoiding any amplification process. The results agree well with those obtained by RT-qPCR or reverse transcription quantitative polymerase chain reaction technique.

Gold nanotriangles (AuNTs) functionalized with dithiolated oligonucleotides have been employed to develop an amplification-free electrochemical biosensor for SARS-CoV-2 in patient samples. Gold nanotriangles, prepared through a seed-mediated growth method and exhaustively characterized by different techniques, serve as an improved electrochemical platform and for DNA probe immobilization. Azure A is used as an electrochemical indicator of the hybridization event. The biosensor detects either single stranded DNA or RNA sequences of SARS-CoV-2 of different lengths, with a low detection limit of 22.2 fM. In addition, it allows to detect point mutations in SARS-CoV-2 genome with the aim to detect more infective SARS-CoV-2 variants such as Alpha, Beta, Gamma, Delta, and Omicron. Results obtained with the biosensor in nasopharyngeal swab samples from COVID-19 patients show the possibility to clearly discriminate between non-infected and infected patient samples as well as patient samples with different viral load. Furthermore, the results correlate well with those obtained by the gold standard technique RT-qPCR, with the advantage of avoiding the amplification process and the need of sophisticated equipment.

Esta investigación intenta dar a conocer los posicionamientos de las instituciones educativas frente a la inclusión escolar y cómo se la aborda desde cada una de ellas, visibilizando estrategias de acompañamiento a las trayectorias en el tránsito del nivel primario al nivel secundario. Por tal motivo, la intención del presente informe es aproximarnos a la realidad de las instituciones de nivel secundarios de la zona sur de la Ciudad de Córdoba en cuanto a la temática de la Inclusión Educativa, iniciando con la conceptualización, tipologías y dimensiones de la articulación desde el paradigma de educación inclusiva y la normativa vigente. A continuación, para el trabajo de campo se consideró oportuno identificar los conocimientos que tienen los distintos actores escolares sobre la inclusión escolar al momento de acompañar las trayectorias escolares y describir los modos de trabajo, metodologías, estrategias y acompañamiento en los procesos de inclusión durante la articulación entre el nivel primario y Ciclo Básico del secundario. Por último se comparten acciones y estrategias recabadas para su socialización. Finalmente, se arribó a la conclusión que pretende reflexionar sobre cómo suceden los procesos de inclusión en el paso entre niveles y compartir estas “buenas prácticas” resignificarlas en pos de una educación inclusiva., Fil: Luna, Mónica Sabrina. Universidad Católica de Córdoba. Facultad de Educación; Argentina., Fil: Maldonado, María Rosa. Universidad Católica de Córdoba. Facultad de Educación; Argentina.

We present a study of the effect of gold nanoparticles (Au NPs) on TiO2 on charge generation and trapping during illumination with photons of energy larger than the substrate band gap. We used a novel characterization technique, photoassisted Kelvin probe force microscopy, to study the process at the single Au NP level. We found that the photoinduced electron transfer from TiO2 to the Au NP increases logarithmically with light intensity due to the combined contribution of electron-hole pair generation in the space charge region in the TiO2-air interface and in the metal-semiconductor junction. Our measurements on single particles provide direct evidence for electron trapping that hinders electron-hole recombination, a key factor in the enhancement of photo(electro)catalytic activity.

In this work, the preparation of regular nanosized columnar structures of titanium dioxide by means of glancing angle deposition with magnetron sputtering (MS-GLAD) followed by thermal annealing is reported. MS-GLAD gives rise to metallic titanium columnar structures with regular width and length that after thermal treatment are fully oxidized to form TiO2 nanocolumns that maintain the morphological features of the original metallic ones. Further functionalization with gold by means of multiple ion cluster source results in well-dispersed Au nanoparticles across the nanocolumns’ surface with a narrow size distribution centered at ca. 8.5 nm. The obtained nanostructures show photocatalytic self-cleaning activity as shown by the elimination of an organic layer deposited on their surface and the detection of hydroxyl radicals. Photoelectrochemical measurements show a better charge separation at the Au/TiO2 interface. In addition, wettability studies show that the degree of hydrophobicity of the surface is increased by the presence of nanocolumns, both in the dark and under UV illumination. This behavior is not modified by the presence of Au nanoparticles on the surface. The obtained results open up interesting implications in the tunability of the properties of nanostructured thin films for this kind of photo-activated application.