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SmCo5/Co core-shell nanoparticles are studied for their ability to improve magnetic properties like coercivity and exchange-bias effects. The core-shell structure helps enhance these properties by allowing better control over the magnetic behaviour of the core, shell, and their interface. These nanoparticles can maintain strong magnetization, high coercivity, and improved energy efficiency. The structure allows for adjustable magnetic properties, giving insights into the core, shell, and their interactions effect on the overall magnetism. We use atomistic magnetic simulations with VAMPIRE software to study the magnetization reversal, coercivity, and Curie temperature in two different combination of exchange-coupled bi-magnetic hard/soft ferromagnetic core/shell nanoparticle. In the first configuration, SmCo5 is the hard magnetic core and Co is the soft magnetic shell. The core size (dc) varies from 0 to 4 nm, while the overall particle size stays around 5 nm. The results show that changing the shell thickness affects the microscopic interface pinning mechanism. Whether SmCo5 is the core with Co as the shell, or vice versa, the coercivity shows little change with variations in shell thickness, but it increases significantly compared to individual Co or SmCo5 nanoparticles. The findings confirm that the core-shell structure depends on the materials, core size, and temperature. We also investigate how the finite-size effect influences the Curie temperature of SmCo5 and Co nanoparticles using M-T graphs. The results show that the maximum energy product (BH)max strongly depends on core size. The SmCo5/Co core-shell nanoparticle combination boosts magnetic performance by utilizing SmCo5's high magnetic strength for permanent magnets and the Co shell's thermal stability for enhanced magnetization. This synergy makes them suitable for applications in permanent magnets, recording media, and biomedical uses. [ABSTRACT FROM AUTHOR]

The Coronavirus Disease 2019 (COVID-19) recently emerged as a life-threatening global pandemic that has ravaged millions of lives. The affected patients are known to frequently register numerous comorbidities induced by COVID-19 such as diabetes, asthma, cardiac arrest, hypertension, and neurodegenerative diseases, to name a few. The expensiveness and probability of false negative results of conventional screening tests often delay timely diagnosis and treatment. In such cases, the deployment of a suitable biosensing platform can readily expedite the rapid diagnosis process for enhanced patient outcomes. We report the development of an electrochemical genosensor based on DNA/OGCN (DNA/oxygenated graphitic carbon nitride) nanohybrids for the quantification of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) DNA─the key biomarker for COVID-19. This is achieved by exploiting the molecular nanowire-formation capability of the [Ru(NH 3 ) 6 ] 2+/3+ redox probe onto the DNA phosphate backbone via electrostatic interactions. The microstructural characterization of OGCN was performed using scanning electron microscopy (SEM) coupled with an energy-dispersive X-ray (EDX) module, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy. The electrochemical analyses were performed using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), while the analytical performance of the sensor was evaluated using square wave voltammetry (SWV). The developed sensor exhibited a wide linear detection range within 10 fM-10 μM, with a limit of detection (LoD) of ∼7.23 fM with a high degree of selectivity toward SARS-CoV-2 target DNA, thereby indicating its potential to be employed in a point-of-care scenario toward providing affordable healthcare to the global populace.

Polysaccharides, found universally in all living-species, exhibit diverse biochemical structures and play crucial roles in microorganisms, animals, and plants to defend against pathogens, environmental stress and climate-changing. Microbial exopolysaccharides are essential for cell adhesion and stress resilience and using them has notable advantages over synthetic polysaccharides. Exopolysaccharides have versatile structures and physicochemical properties, used in food systems, therapeutics, cosmetics, agriculture, and polymer industries. Immense economic and infrastructural constraints hinder its widespread commercial use, necessitating a deeper understanding of metabolic-pathways amidst changing environmental climate that influences the biomass composition of EPS-producing wild-microbes. Green and sustainable extraction of EPS from microbes followed by commercial product development has still not been exploited comprehensively. Yield of EPS production vary from 0.1 to 3 g/g of cell weight, influenced by fermentation conditions. Economic barriers, including substrate and processing costs, limit commercial viability. Key biosynthetic pathways involve glycosyltransferases enzymes, whose regulatory network gaps and substrate specificity remain areas for optimization. Addressing these could enhance yields and lower production costs. Review illustrates various microbial-exopolysaccharides, influencing factors of production, and offer valuable insights on the bioplastic, biofuel, agri-bioproduct, and biomedicine. But their bioprospecting potential is yet to be exhaustively explored, along with their pros and cons nor documented comprehensively in scientific literature., Competing Interests: Declaration of competing interest The authors state that they have no known personal relationships or financial interests that would have seemed to affect the work this paper reports., (Copyright © 2025. Published by Elsevier B.V.)