Science Reviews - from the end of the world

Encuentro de Superficies y Materiales Nanoestructurados - NANO 2022: An open window to the last news in nanotechnology applications

Cristina Hoppe — Wed, 22 Nov 2023 00:00:00 -0800

With more than two decades of existence, the “Encuentro de Superficies y Materiales Nanoestructurados” remains a national benchmark for the scientific and technological prowess of Argentina’s “Nano” community. The event began in 2001 at the National Atomic Energy Commission in Bariloche and developed into what it is today: on the one hand, a national gathering that brings together a wide range of disciplines to discuss and disseminate the most recent findings in nanoscience and nanotechnology; on the other hand, a place where friends and colleagues can talk freely and honestly about a wide range of topics related to research, management, transfer to industry, and education in this vibrant field of science and technology. The event took place in San Carlos de Bariloche until 2010. Following then, it was held in Córdoba (2012), Mar del Plata (2013), Bariloche (2014), Rosario (2015), Buenos Aires (2016), Bariloche (2017), La Plata (2018), Buenos Aires (2019), and Mar del Plata (virtual in 2021). The National University of Río Cuarto, along with participants from the CONICET-UNRC institutes IITEMA, IDAS, and INBIAS, organized NANO 2022 during August 9–11, 2022.

Fe-based high-temperature superconductivity: Impact of atomic defects in the electronic states

Yanina Fasano — Wed, 22 Nov 2023 00:00:00 -0800

A brief review on the impact of atomic defects in the electronic properties of Fe-based super conductors is hereby presented, focusing in particular on the FeSe family of superconductors. This family of compounds captured the attention of the scientific community during the last decade since its simple crystal structure seemed to be an advantage in understanding the microscopic mechanisms mediating high-temperature superconductivity in Fe-based superconductors. Now, more than 14 years of intense research around the world have elapsed since the discovery of the so-called iron age of superconductivity, and nevertheless it is still debated which is the origin of superconductivity in these compounds. One thing stands for certain in all the enquiries: There is a subtle interplay between defects or local variations in the crystal structure and the electronic states in Fe-based superconductors. This review presents an overview on the main contributions of the community in this interplay in the particular case of the FeSe family and provides a critical discussion on some of the points that still need to be studied in order to provide a thorough quantitative understanding of this issue.

Membrane-peptide interaction: Focusing on membrane properties

Wed, 22 Nov 2023 00:00:00 -0800

Cellular membranes compartmentalize cells, comprise a permeability barrier, and are the starting place for several signaling cascades and processes in which lateral diffusion of molecules is a key factor. Although it has been shown that organisms adapt the lipid composition of their membranes in order to maintain these in a mainly fluid state, several studies point to the coexistence of regions with different compositions and mechanical properties. In this context, while proteins have been related to solid docks, sterols are accepted as liquid-ordered phase state inducers. Thus, the current model for membranes is a patchwork-like surface, with the different regions being highly variable in size and very dynamic.
Many peptides, like cationic antimicrobial peptides and cell penetrating peptides, target cell membranes. The affinity of these soluble peptides to membranes depends on membrane features such as composition, charge density, compaction, and fluidity. As a consequence of the patchwork-like character of the membrane, regions with a broad spectrum of properties are available to interact with these peptides. Therefore, it is important to know how peptide-membrane interaction depends on membrane properties, and also what happens with the membranes after the interaction.
Here, we summarize our contribution to understanding how the interaction of peptides with membranes is modulated by membrane properties. The influence of the phase state, electrostatics, and chemical composition of the membrane on peptide binding is described using biomimetic systems. The effect of peptide association on membrane properties is also revisited. Finally, possible extrapolations to cells are discussed.

Magnetic nanoparticles for purification of biomolecules: challenges and opportunities

Wed, 22 Nov 2023 00:00:00 -0800

The purification and/or concentration of biomolecules from complex mixtures constitutes one of the fundamental steps in the processes involved in biotechnology and, in particular, in the diagnostic methods of human and veterinary diseases. Most purification procedures are based on the interaction between a solid phase and the biomolecule to be purified (RNA, DNA, proteins, etc.), involving several steps with dependence on the method used. Among the different approaches, the use of functionalized magnetic nanoparticles (MNPs) has become of increasing interest due to its efficiency, practicality and the possibility of automation. In this work we present preliminary results on the use of MNPs for the purification of nucleic acids and recombinant proteins.

Nanotechnological tools for the groundwater remediation: From lab to the real environments

Verónica Lassalle — Wed, 22 Nov 2023 00:00:00 -0800

The presence of nanomaterials in our everyday life has largely grown during the last years. They have emerged as relevant tools to find solutions to old problems. Among the areas where nanotechnology and nanomaterials have shown value, environmental remediation appears as an important one. The capability to tune the nanomaterial´s properties and characteristics to confer specific properties to eliminate target pollutants, accentuates the potential of these materials. The purification of water for human consumption or industrial process is currently of priority due to the increasing demand and reduction of the available water sources. This point of view article intends to show that the assays performed in the lab are not sufficient to validate large scale processes. Removal of contaminants in real aqueous environments require that due consideration is given to the behavior of the nanomaterial in field processes, because changes in efficiency and lack os stability may result in these conditions.

Synthesis, characterization and application of a mesoporous nanomaterial integrated in a bioanalytical microsensor with electrochemical detection for the determination of mycotoxin T2 in samples of agri-food interest

Alex Simioli, Jhonny Villarroel Rocha, Martin Fernández Baldo — Wed, 22 Nov 2023 00:00:00 -0800

An ordered mesoporous material (OMM) type SBA-16 was synthesized from sol gel type reactions and the self-assembly of surfactants. Once SBA-16 was obtained, it was functionalized with APTES (3-aminopropyltriethoxysilane) on the one hand and with MEA (monoethanolamine) on the other. Subsequently, the characterization of these nanomaterials was carried out using Scanning Electron Microscopy (SEM), Energy Disperse Spectroscopy (EDS), Infrared Spectroscopy (FTIR), N2 adsorption-desorption and X-ray Diffraction (XRD). In addition, a biosensor was developed where the central channel was modified with the material obtained SBA-16 (MEA) and a commercial ELISA Kit (enzymatic immunoassay) was used for a quantitative determination of the mycotoxin T-2 and compared with the analytical results of our generated biosensor.