Nanostructured transition metal oxides (TMO) are extensively explored materials for non-enzymatic glucose sensors. TMOs such as Iron oxides( α-Fe2O3, γ-Fe2O3, Fe3O4, etc.), NiO, CuO, Cr2O3, etc. have been utilized as electrocatalysts for glucose determination. Tremendous efforts have been put into identifying the impact of different morphologies of these materials on the glucose-sensing performance. The larger surface area of the flower and wire-shaped catalysts make them better performing amongst other morphologies. Interestingly, it is important to note that most of such studies are on standard Glassy Carbon electrodes. Further to enhance the Electrochemically active surface area (ECSA) of the electrode, Carbon nanomaterials such as reduced Graphene Oxide (r-GO) and Carbon Nanotubes (CNTs) are used as additives. Exfoliated Graphite paper electrodes offer better electrochemical characteristics than GCE electrodes due to their much larger ECSA. This study presents the non-enzymatic glucose sensing properties of NiO nanoflower-decorated Exfoliated Graphite electrodes. The amperometric detection of glucose shows a linear increase in current over a physiologically relevant wide range
Microplastics (MPs) are ubiquitous in all ecosystems, affecting wildlife and, ultimately, human health. The complexity of natural samples plus the unspecificity of their treatments to isolate polymers renders the characterization of thousands of particles impractical for environmental monitoring using conventional spectroscopic techniques. Two primary solutions are to analyze a small fraction of the sample or to measure only a subset of particles present over a holder, known as subsampling. A strategy to subsample reflective Kevley slides and gold-coated filters using quantum-cascade laser-based infrared imaging is proposed here, as this technology is a promising tool for MPs monitoring. In contrast to most previous approaches that struggle to propose general subsampling schemes, we introduce the concept of sample-based subsampling. This can be applied ex-ante always and it highlights the best subsampling areas for a sample after a preliminary assay to count the total number of particles on a holder. The error at this stage acts as a proxy to minimize errors when evaluating the number of particles and MPs, significantly enhancing the feasibility of large-scale MPs monitoring. The p
In this work we present and evaluate a radiochemical procedure optimised for the analysis of $^{236}$U and $^{239,240}$Pu in seawater samples by Accelerator Mass Spectrometry (AMS). The method is based on Fe(OH)$_3$ co-precipitation of actinides and uses TEVA and UTEVA extraction chromatography resins in a simplified way for the final U and Pu purification. In order to improve the performance of the method, the radiochemical yields are analysed in 1 to 10 L seawater volumes using alpha spectrometry (AS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Robust 80% plutonium recoveries are obtained; however, it is found that Fe(III) concentration in the precipitation solution and sample volume are the two critical and correlated parameters influencing the initial uranium extraction through Fe(OH)$_3$ co-precipitation. Therefore, we propose an expression that optimises the sample volume and Fe(III) amounts according to both the $^{236}$U and $^{239,240}$Pu concentrations in the samples and the performance parameters of the AMS facility. The method is validated for the current setup of the 1 MV AMS system (CNA, Sevilla, Spain), where He gas is used as a stripper, by analysing
A simple and fast radiochemical procedure for the sequential extraction of U, Np and Pu from small-volume seawater samples ($<10$ L) is presented. The method has been developed and optimized for the final determination of $^{236}$U, $^{237}$Np, $^{239}$Pu and $^{240}$Pu by Accelerator Mass Spectrometry (AMS). It is based on the use of $^{242}$Pu as tracer for both Np and Pu isotopes. Samples are pre-concentrated by Fe(OH)$_2$ co-precipitation. TEVA and UTEVA resins are used in a very simplified way for the final purification of the Pu+Np and U fractions, respectively. The radiochemical yields of the three elements have been investigated in detail by alpha spectrometry (AS) and gamma spectrometry (GS). The obtained results indicate high and robust chemical yields for the three elements and similar ones for Pu and Np. Furthermore, the use of $^{242}$Pu as tracer for $^{237}$Np is validated by analyzing a reference seawater sample (IAEA-443) by radiometric techniques. We demonstrated that, if chemicals are properly chosen, processed blank levels can be kept at the same level of the extremely low detection limits that can be achieved by AMS ($10^5 - 10^6$ atoms/sample). The procedur
Magnetic resonance microimaging (MR mu I) is an outstanding technique for studying water transfers in millimetric bio-based materials in a non-destructive and non-invasive manner. However, depending on the composition of the material, monitoring and quantification of these transfers can be very complex, and hence reliable image processing and analysis tools are necessary. In this study, a combination of MR mu I and multivariate curve resolution-alternating least squares (MCR-ALS) is proposed to monitor the water ingress into a potato starch extruded blend containing 20% glycerol that was shown to have interesting properties for biomedical, textile, and food applications. In this work, the main purpose of MCR is to provide spectral signatures and distribution maps of the components involved in the water uptake process that occurs over time with various kinetics. This approach allowed the description of the system evolution at a global (image) and a local (pixel) level, hence, permitted the resolution of two waterfronts, at two different times into the blend that could not be resolved by any other mathematical processing method usually used in magnetic resonance imaging (MRI). The re
Simple and low-cost biosensing solutions are suitable for point-of-care applications aiming to overcome the gap between scientific concepts and technological production. To compete with sensitivity and selectivity of golden standards, such as liquid chromatography, the functionalization of biosensors is continuously optimized to enhance the signal and improve their performance, often leading to complex chemical assay development. In this research, the efforts are made on optimizing the methodology for electrochemical reduction of graphene oxide to produce thin film-modified gold electrodes. Under the employed specific conditions, 20 cycles of cyclic voltammetry (CV) are shown to be optimal for superior electrical activation of graphene oxide into electrochemically reduced graphene oxide (ERGO). This platform is further used to develop a matrix metalloproteinase 2 (MMP-2) biosensor, where specific anti-MMP2 aptamers are utilized as a biorecognition element. MMP-2 is a protein which is typically overexpressed in tumor tissues, with important roles in tumor invasion, metastasis as well as in tumor angiogenesis. Based on impedimetric measurements, we were able to detect as low as 3.32
The tetanus neurotoxin (TeNT) is one of the most toxic proteins known to man, which prior to the use of the vaccine against the TeNT producing bacteria Clostridium tetani, resulted in a 20 % mortality rate upon infection. The clinical detrimental effects of tetanus have decreased immensely since the introduction of global vaccination programs, which depend on sustainable vaccine production. One of the major critical points in the manufacturing of these vaccines is the stable and reproducible production of high levels of toxin by the bacterial seed strains. In order to minimize time loss, the amount of TeNT is often monitored during and at the end of the bacterial culturing. The different methods that are currently available to assess the amount of TeNT in the bacterial medium suffer from variability, lack of sensitivity, and/or require specific antibodies. In accordance with the consistency approach and the three Rs (3Rs), both aiming to reduce the use of animals for testing, in-process monitoring of TeNT production could benefit from animal and antibody-free analytical tools. In this paper, we describe the development and validation of a new and reliable antibody free targeted LC-
A mysterious cosmic explosion has astronomers buzzing, as a strange event may hint at an entirely new kind of stellar cataclysm。 After detecting ripples in space-time, scientists spotted a fast-fading red glow that initially looked like a rare kilonova—the kind of collision that forges gold and uranium。 But just days later, the signal shifted, beha
As the Moon swallowed the Sun during the April 8, 2024, total solar eclipse, something remarkable happened on the ground—cities went eerily quiet。 Scientists analyzing seismic data found that human-generated vibrations, usually caused by traffic, construction, and daily activity, dropped sharply during totality。 The effect was so pronounced that it
A group of undergraduate students pulled off something remarkable: they built their own dark matter detector and used it to probe one of physics’ biggest mysteries。 Working with limited resources but plenty of creativity, they designed a stripped-down experiment to hunt for axions — hypothetical particles that could make up dark matter
A major discovery is reshaping how scientists think about catalysts。 Researchers have, for the first time, captured oxygen atoms moving through the interior of a catalyst—not just along its surface。 This reveals that the bulk material can actively participate in reactions, opening a new frontier in catalyst design
Scientists have uncovered the true boundary of the Milky Way’s star-forming region using stellar “age mapping。” They found a telltale U-shaped pattern showing that star formation drops sharply around 35,000–40,000 light-years from the center。 Beyond that, stars are mostly migrants, slowly drifting outward rather than forming in place
Researchers have, for the first time, directly visualized how electronic patterns known as charge density waves evolve across a phase transition。 Using cutting-edge microscopy, they found these patterns form unevenly, breaking into patches influenced by tiny structural distortions。 Unexpectedly, small pockets of order persist even above the transit
A massive cosmic milestone has just been reached: scientists have completed the largest high-resolution 3D map of the universe ever created。 Built using data from over 47 million galaxies and quasars, this map could unlock new clues about dark energy—the mysterious force driving the universe’s expansion。 Despite setbacks like wildfire disruptions,
A breakthrough in brain-inspired computing could make today’s energy-hungry AI systems far more efficient。 Researchers have engineered a new nanoelectronic device using a modified form of hafnium oxide that mimics how neurons process and store information at the same time。 Unlike conventional chips that waste energy moving data back and forth, this
Scientists have created tiny “optical tornadoes” — swirling beams of light that twist like miniature whirlwinds — using a surprisingly simple setup based on liquid crystals。 Instead of relying on complex nanotechnology, the team used self-organizing structures called torons to trap and manipulate light, causing it to spiral and rotate in intricate
Scientists have unveiled a breakthrough imaging method that can capture the hidden details of events unfolding in trillionths of a second。 This new technique doesn’t just track how bright something is—it also reveals subtle structural changes that were previously invisible, all in a single shot。 By effectively turning ultrafast phenomena into detai
A major physics experiment has uncovered evidence for a strange new form of matter, where a fleeting particle gets trapped inside a nucleus。 This exotic state may reveal how mass is generated, suggesting that particles can weigh less when surrounded by dense nuclear matter。 The findings support long-standing theories about how the vacuum of space i