Enhancing Interplanar Spacing in V2O3/V3O7 Heterostructures to Optimize Cathode Efficiency for Zn-Ion Batteries.

The improvement of sophisticated cathode materials plays a major role in boosting the efficiency of Zn-ion batteries. These batteries have garnered considerable interest as a result of their excellent energy density and the promise of cost-effective solutions for energy storage. In this work, we present a novel approach to progress the electrochemical investigation of Zn-ion batteries by expanding the interplanar distance of layered hydrated V2O3/V3O7 heterostructure nanosheets. Electrochemical investigations were conducted to assess the effectiveness of the stacked hydrated V2O3/V3O7 heterostructure as a cathode component for Zn-ion batteries. The expanded interplanar space as a result of the introduction of water molecules facilitates the insertion/extraction of Zn ions, leading to significantly enhanced electrochemical characteristics. The layered hydrated V2O3/V3O7 heterostructure exhibited an impressive specific capacity of 330 mAh g-1 at a current density of 0.1 A g-1, maintaining a capacity retention of approximately 92.3% and a coulombic efficiency of 95.8% even after 2000 cycles.

Rapidly derived equimolar Ca: P phasic bioactive glass infused flexible gelatin multi-functional scaffolds - A promising tissue engineering.

The study aims to design and fabricate an ultra-easier multi-functional biomedical polymeric scaffold loaded with unique equimolar Ca:P phasic bioactive glass material (BG). Gelatin (G) - 45S5 bioactive glass (BG) scaffolds were synthesized via a simple laboratory refrigerator with higher biocompatibility and cytocompatibility. The results proved that BG has enhanced bio-mineralization of the scaffolds and results support that the G: BG (1:2) ratio is the more appropriate composition. Brunauer-Emmett-Teller (BET) study confirms the higher surface area for pure Gelatin and G: BG (1:2). Scanning Electron Microscopic images display the precipitation of hydroxycarbonate apatite layer over the scaffolds on immersing it in simulated body fluid. Alkaline phosphate activity proved that G: BG (1:2) scaffold could induce mitogenesis in MG-63 osteoblast cells, thus helping in hard tissue regeneration. Sirius red collagen deposition showed that higher content bioactive glass incorporated Gelatin polymeric scaffold G: BG (1:2) could induce rapid collagen secretion of NIH 3T3 fibroblast cell line that could help in soft tissue regeneration and earlier wound healing. The scaffolds were also tested for cell viability using NIH 3T3 fibroblast cell lines and MG 63 osteoblastic cell lines through methyl thiazolyl tetrazolium (MTT) assay. Thus, the study shows a scaffold of appropriate composition G: BG (1:2) can be a multifunctional material to regenerate hard and soft tissues.

A Review of Electroactive Nanomaterials in the Detection of Nitrogen-Containing Organic Compounds and Future Applications.

Electrochemical and impedimetric detection of nitrogen-containing organic compounds (NOCs) in blood, urine, sweat, and saliva is widely used in clinical diagnosis. NOC detection is used to identify illnesses such as chronic kidney disease (CKD), end-stage renal disease (ESRD), cardiovascular complications, diabetes, cancer, and others. In recent years, nanomaterials have shown significant potential in the detection of NOCs using electrochemical and impedimetric sensors. This potential is due to the higher surface area, porous nature, and functional groups of nanomaterials, which can aid in improving the sensing performance with inexpensive, direct, and quick-time processing methods. In this review, we discuss nanomaterials, such as metal oxides, graphene nanostructures, and their nanocomposites, for the detection of NOCs. Notably, researchers have considered nanocomposite-based devices, such as a field effect transistor (FET) and printed electrodes, for the detection of NOCs. In this review, we emphasize the significant importance of electrochemical and impedimetric methods in the detection of NOCs, which typically show higher sensitivity and selectivity. So, these methods will open a new way to make embeddable electrodes for point-of-detection (POD) devices. These devices could be used in the next generation of non-invasive analysis for biomedical and clinical applications. This review also summarizes recent state-of-the-art technology for the development of sensors for on-site monitoring and disease diagnosis at an earlier stage.

Layered Structures of Enriched V5+ States of Vanadium Oxide as a Hybrid Cathode Material for Long-Cyclable Aqueous Zinc-Ion Batteries.

Recently, aqueous zinc-ion batteries (AZIBs) have garnered much attraction because of their ecofriendly nature, cost effectiveness, and reliability. However, there are still many challenges in developing suitable cathode materials for practical usage in ZIBs. In this work, we have synthesized a layered V5+-rich vanadium oxide (V6O13) flaky structure that provided the electrolyte with a large active surface area. In addition to that, the mixed (V4+/V5+) valence states of V have significantly improved the ionic diffusion of Zn2+, thereby improving the V6O13 electrical conductivity. Therefore, the AZIBs based on the layered structure V6O13 cathode with 1 M ZnSO4 electrolyte exhibited a very high specific capacity of 394 mAh g-1 @ 0.1 A g-1 without the addition of any additives or electrode modification. The rate capability and cycle life are investigated at the current density of 2 A g-1, where the capacity retention was found to be around 94% along with a coulombic efficiency of 96% for over 100 cycles. Such a material with high electrochemical performance can be used for portable electronic devices and electric vehicular applications.

Influence of pH in the synthesis of calcium phosphate based nanostructures with enhanced bioactivity and pro-angiogenic properties.

In synthetic fabrication, the process parameters decide the growth nucleation, phase translation, and the evolution of morphological facets of nanostructured materials. This work demonstrates the formation of different crystallographic phases of calcium phosphate by the influence of pH from acidic to alkaline conditions and also investigated their bone regeneration, protein adsorption, and pro-angiogenic properties. Present results illustrate that the alteration of pH is the crucial factor for the synthesis of calcium phosphate (CP) phases. The structural analysis reveals the monetite (CaHPO4 ) phase with a triclinic crystal system for pH 5, dual-phase of monetite combined with hydroxyapatite at the neutral pH 7, and pure phase of hydroxyapatite (Ca10 [PO4 ]6 OH2 ) with hexagonal structure at pH 10. Microscopic analysis portrays the cubic and rod-like morphologies by changing the pH values. FTIR and RAMAN spectroscopic analyses confirm the stretching, bending, and vibrational modes of dominant phosphate groups of different CP phases. Further, the biocompatibility of the prepared CP phases was examined by hemolysis assay, which showed less than 2% of lysis and enhanced cell viability. Moreover, the bioactivity study revealed rapid mineralization and a higher protein adsorption rate for the monetite CP phase (M-CP). Subsequently, the chick embryo angiogenesis assay elucidated 33% higher neovascularization for M-CP compared with the other two CP phases. The fabricated M-CP nanostructure constitutes a promising candidate for biomedical applications.

Hybrid ZnO nanostructures modified graphite electrode as an efficient urea sensor for environmental pollution monitoring.

Herein, we propose a facile electrochemical sensing platform for urea detection using pencil graphite electrode modified nanocomposites of CuO/ZnO and Fe2O3/ZnO. The detection of urea is essential to monitor for identifying its pollution in the water, at the soil surface and in diagnosing urea cycle disorder related diseases. Therefore, an effective, accurate, cost-effective method of diagnosis is urgently needed. Nanostructured metal oxides have the potential ability to detect molecules even at trace level and to explore this, the present work is formulated with Cu and Fe based ZnO nanocomposites for enhancing the sensing performance towards electrochemical sensing of urea. The sensing responses were confirmed from the increase in oxidation current with respect to the concentration of urea. The results show that Fe2O3/ZnO coated graphite electrode has a higher response against urea compared to ZnO and CuO/ZnO. The cyclic voltammetry studies also validate urea sensing of Fe-ZnO in the linear range of 0.8 µg/mL to 4 µg/mL, with the detection limit of 2.5 µg/mL. This suggests that the cost-effective pencil graphite electrode modified Fe2O3/ZnO can be utilized as a promising analytical tool for urea sensing.

Sustainable multilayer biomass carbon and polymer hybrid column as potential antibacterial water filter.

Stipulation of fresh water for domestic use without any microbial, organic and inorganic contaminants is of high need. Sustainable, efficient, cost-effective and robust water purification technologies is of high need and it can be achieved using nanomaterials and their composite. Nanostructured graphene has unique properties like high surface to volume ratio, higher absorbability, reusability with minimal chemical alterations, and low cytotoxicity. From the validation of these properties, we have developed PLLA-Ag@graphene sandwich structures as an effective adsorbate for water purification application. As the real water bodies have lot of bacterial contaminants, the material is also designed as efficient adsorbate with antibacterial efficacy. In view of achieving these objectives, we have synthesized PLLA fibre mats by electrospinning method, followed by PLLA-Graphene and Ag decorated PLLA-graphene mats. The crystallite size for graphite and Ag@graphene was calculated as 30.82 nm and 43.79 nm, respectively. Furthermore, the UV analysis of Ag@graphene shows two peaks corresponding to graphene and Ag NP at 285 nm and 407 nm respectively. The layers were assembled in the order of polymeric fibre, as-fired biomass graphite, Ag@graphene for methodical filtration process. The filtration efficacy of the filtrate was tested using sewage water and the results shows higher contamination removal percentage of 87 % with TDS values in the drinking water standards after filtration. The antibacterial efficacy results also evidence of the potentialities of the hybrid system towards water purification application.

Pulsed laser deposition of nanostructured bioactive glass and hydroxyapatite coatings: Microstructural and electrochemical characterization.

Bioactive coatings on metallic implants promote osseointegration between bone and implant interfaces. A suitable coating enhances the life span of the implant and reduces the requirement of revision surgery. The coating process needs to be optimized such that it does not alter the bioactivity of the material. To understand this, the biocompatibility of nanostructured bioactive glass and hydroxyapatite-coated Titanium substrate by pulsed laser deposition method is evaluated. Raman and IR spectroscopic techniques based on silica and phosphate functional groups mapping have confirmed homogeneity in coatings by pulse laser deposition method. Comparative studies on nanostructured bioactive glass and hydroxyapatite on titanium surface elaborated the significance of bioactivity, hemocompatibility, and cytocompatibility of the coated surface. Notably, both hydroxyapatite and bioactive glass show good hemocompatibility in powder form. Hemocompatibility and cytocompatibility results validate the enhanced sustenance for hydroxyapatite coating. These results signify the importance of the choice of coating methodology of bioceramics towards implant applications.

Bio-inspired multifunctional collagen/electrospun bioactive glass membranes for bone tissue engineering applications.

Treatment of bone disease and disorders is often challenging due to its complex structure. Each year millions of people needs bone substitution materials with quick recovery from diseases conditions. Synthetic bone substitutes mimicking structural, chemical and biological properties of bone matrix structure will be very obliging and of copious need. In this work, we reported on the fabrication of bioinspired, biomimetic, multifunctional bone-like three-dimensional (3D) membranes made up of inorganic bioactive glass fibers matrixed organic collagen structure. The 3D structure is arranged as a stacked-layer similar to the order of apatite and neotissue formation. Comparative studies on collagen, collagen with hollow and solid bioactive glass fibers evidenced that, collagen/hollow bioactive glass is mechanically robust, has optimal hydrophilicity, simultaneously promotes bioactivity and in situ forming drug delivery. The 3D membrane displays outstanding mechanical properties apropos to the bioactive glass fibers arrangement, with its Youngs modulus approaching the modulus of cortical bone. The in vitro cell culture studies with fibroblast cells (3T3) on the membranes display enhanced cell adhesion and proliferation with the cell alignment similar to anisotropic cell alignment found in the native bone extracellular matrix. The membranes also support 3D cell culturing and exhibits cell proliferation on the membrane surface, which extends the possibility of its bone tissue engineering application. The alkaline phosphatase assessment and alizarin red staining of osteoblast cells (MG63) depicted an enhanced osteogenic activity of the membranes. Notable Runx2, Col-Type-1 mRNA, osteocalcin, and osteonectin levels were found to be significantly increased in cells grown on the collagen/hollow bioactive glass membrane. This membrane also promotes vascularization in the chick chorioallantoic membrane model. The results altogether evidence this multifunctional 3D membrane could potentially be utilized for treatment of bone defects.

Chitosan mediated 5-Fluorouracil functionalized silica nanoparticle from rice husk for anticancer activity.

Herein, we have reported a cost-effective method of synthesizing highly efficient silica nanomaterial from rice husks for its application as a chemotherapeutic agent. Silica particle with two different sizes ~20 nm and ~40 nm were achieved from silica precursor obtained from rice husk. 5-Fluorouracil was functionalized onto the surface of silica nanoparticles by direct conjugation and chitosan mediated conjugation. Particle size analysis, zeta potential and functional analyzes were performed in systematic methodology to confirm chitosan coating and 5-Fluorouracil conjugation on silica nanoparticles. The drug loading percentage with respect to the particle size shows that ~20 nm particles have higher loading capacity. The chitosan mediated conjugation of drug shows sustained release in acidic pH and hence suitable for cancer cell-targeted delivery. The in vitro cell culture studies performed on MC3T3 fibroblast cell lines, MCF-7 and A549 cancer cell lines depicts that, compared to direct conjugation of 5-Fluorouracil, chitosan mediated drug conjugation on the surface of silica nanoparticles shows lesser toxic to fibroblast cell lines and higher toxicity towards cancer cell lines. The results of this toxicity were also confirmed from the nucleic acid spectral signature of Raman spectra treated with drug conjugated silica nanoparticles.