Fabrication of chitosan-coated mixed spinel ferrite integrated with graphene oxide (GO) for magnetic extraction of viral RNA for potential detection of SARS-CoV-2

Genetic variants of the COVID-19 causative virus have been arising and circulating globally. In many countries especially in developing ones with a huge population, vaccination has become one of the major challenges. SARS-CoV-2 variants’ fast transmission rate has upsurge the COVID cases, leading to more stress on health systems. In the current COVID-19 scenario, there is the requirement of more adequate diagnostic approaches to check the COVID-19 spread. Out of many diagnostic approaches, a magnetic nanoparticle-based reverse transcription-polymerase chain reaction could be nontrivial. The use of magnetic nanoparticles to separate nucleic acid of SARS-CoV-2 from the patient samples and applied for detection is an easy and more effective way for COVID-19 patient detection. Herein, the magnetic nanoparticles are synthesized using the sol-gel autocombustion methods and then, successfully coated with biopolymer (chitosan) using ultra-sonication. Chitosan-coated nanoparticles are successfully integrated into the graphene oxide sheets to introduce carboxyl groups. Crystallite size calculation, morphological and magnetic studies of synthesized magnetic nanoparticles, and multifunctional magnetic nanoparticles are done using XRD, SEM, TEM, and VSM respectively. Besides the potentiality of the fabricated nanocomposites in RNA extraction protocol is also discussed with schematic representation.

Raman Spectroscopic and Electrochemical Measurements of Dynamic Shocked MnFe2O4 Nano-Crystalline Materials

Divalent ferrite nano-crystalline materials subjected to shock wave recovery analysis have received non-debatable attention among the materials scientists due to their outstanding contribution that has fueled the enrichment of high-pressure ferrites science which act as the focal-point of the current research theme. On those lines, we intend to provide the Raman spectroscopic and electrochemical measurements of manganese ferrite nanoparticles (MnFe2O4 NPs) at dynamic shocked conditions. Raman spectroscopic analysis has revealed the stability of the tetrahedral (A-site) and octahedral (B-sites) sites of Mn2+ ions as well as Fe3+ ions at shocked conditions. Cyclic-voltammetry (CV-analysis) and impedance spectroscopic measurements of shocked samples have demonstrated the electro-chemical properties of MnFe2O4 NPs whose electrical conductivity is found to be reduced while increasing the number of shock pulses. The consolidated results provide the solid evidence that the test sample’s crystal structure does not undergo any crystallographic phase transitions or mixed spinel states at shocked conditions.

Microstructure and Magnetic properties of ferrite nanoparticles synthesized by Co-precipitation method

In the current research, Cu0.5Co0.3Mo0.2Fe2O4 mixed ferrite nanoparticles have been synthesized using Co-precipitation method. XRD patterns show the development of polyphasic copper, cobalt and molybdenum mixed spinel composition. The particle size of ferrite system is 16nm and they are nanoparticles. The lattice constant was determined to be 8.368 Å used for the highest peak (311). FTIR spectroscopy shows the lower octahedral and higher tetrahedral frequency alignment of ions in the spinel ferrite leading to the octahedral 550 cm− 1 and the tetrahedral 471 cm− 1 vibration modes. TEM micrographs showed spherical morphology and their particle size less than 50 nm, which correlated XRD crystallite size. VSM shows excellent ferrimagnetic properties because of higher coercivity (985.29 G). These higher coercivity materials can make cathode content for Li-ion batteries.

Chapter 5.2b Erebus Volcanic Province: petrology

Igneous rocks of the Erebus Volcanic Province have been investigated for more than a century but many aspects of petrogenesis remain problematic. Current interpretations are assessed and summarized using a comprehensive dataset of previously published and new geochemical and geochronological data. Igneous rocks, ranging in age from 25 Ma to the present day, are mainly nepheline normative. Compositional variation is largely controlled by fractionation of olivine + clinopyroxene + magnetite/ilmenite + titanite ± kaersutite ± feldspar, with relatively undifferentiated melts being generated by <10% partial melting of a mixed spinel + garnet lherzolite source. Equilibration of radiogenic Sr, Nd, Pb and Hf is consistent with a high time-integrated HIMU sensu stricto source component and this is unlikely to be related to subduction of the palaeo-Pacific Plate around 0.5 Ga. Relatively undifferentiated whole-rock chemistry can be modelled to infer complex sources comprising depleted and enriched peridotite, HIMU, eclogite-like and carbonatite-like components. Spatial (west–east) variations in Sr, Nd and Pb isotopic compositions and Ba/Rb and Nb/Ta ratios can be interpreted to indicate increasing involvement of an eclogitic crustal component eastwards. Melting in the region is related to decompression, possibly from edge-driven mantle convection or a mantle plume.