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• A novel hybrid nanostructure (Ag-Cu2O@TNTs) highly sensitive cholesterol biosensor was fabricated. • The biosensor showed great sensitivity, good stability, and selectivity along with a low detection limit. • The optimization of process parameters, including pH, and temperature was successfully conducted during the electrochemical sensing procedures. • The developed electrode accurately detected cholesterol in human blood serum. We developed a highly sensitive non-enzymatic biosensor based on hybrid Ag-Cu 2 O@TNTs nanostructure aggregate for the detection of cholesterol. A facile anodization process on a thin titanium alloy (Ti6Al4V) plate was achieved to deposit TiO 2 nanotubes (TNTs). Subsequently, TNTs was decorated with Cu 2 O nanomaterials (NM) using wet chemical bath deposition (CBD) technique. The electro-deposition of silver (Ag) nanoparticles on Cu 2 O@TNTs hybrid aggregate produced high electroactive surface area which enhanced the electron transfer rate. The structure of Ag-Cu 2 O@TNTs was examined using X-ray diffraction (XRD), transmission emission microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). Cyclic voltammetry (CV) and amperometry techniques were utilized to study the electrochemical behaviour of nanostructures. The hybrid nanostructure demonstrated great sensitivity (12140.06 μAmM−1cm−2) compared to pure TNTs and Cu 2 O@TNTs with low detection limit (0.057 mM) and fast response. This study highlights exciting potential of nanocomposites in advancement of reproducible and selective biosensor applications. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) are strongly linked with oxidative stress (OS) generated during the process of sperm cryopreservation. Indeed, cellular damage from ROS has been implicated during sperm cryopreservation which causes deterioration in sperm quality and antioxidant nanoparticles (NPs) have been successful in preventing such damage. The interaction of NPs with sperm cells has been less frequently explored in farm animals. The present study explored the effect of NP supplementation on sperm ultrastructure, potential interaction with sperm membrane (plasma and acrosome membrane), heat shock protein (HSP) gene expression levels and sperm quality in cryopreserved buck semen. Thirty-two (32) ejaculates were collected from four (4) adult male bucks and then diluted in Tris- citric acid- fructose- egg yolk (TCFY) extender containing the Zinc-oxide (ZnO) and Selenium (Se) NP treatments (T0: Control; TZn: 0.1 mg/mL ZnO NPs and TSe: 1 µg/mL Se NPs) after initial evaluation. Diluted semen was packed in 0.25 mL French mini straws and then stored in liquid nitrogen (LN 2). Sperm parameters, lipid peroxidation (LPO) profile, sperm head morphology ultrastructural classification under transmission electron microscope (TEM), potential interaction of NPs with sperm membrane and expression of HSP genes were evaluated in the different treatment groups. We found a significant (p < 0.05) increase in the percentage of spermatozoa with intact plasma membrane, and intact acrosome in the ZnO (0.1 mg/mL) and Se (1 µg/mL) NP supplemented groups in comparison to the frozen control group. TEM assessment revealed no internalization of both ZnO and Se NPs into the sperm structure. Few occasional contacts of ZnO NPs with the sperm membrane and a few agglomerates of Se NPs around the area of damaged membranes were visualized. HSP70 and HSP90 mRNA levels were significantly (p < 0.001) higher in the NP supplemented groups in comparison to the control. HSP70 and HSP90 mRNA levels had a strong positive association with sperm motility and a weak to moderate association with other sperm parameters. Current findings indicated that ZnO NPs are more potent than Se NPs in ameliorating peroxidative damages during sperm cryopreservation, increases semen quality parameters possibly by increasing the expression levels of HSP genes in buck semen. Furthermore, NP supplementation may have a potential role in preserving sperm head ultrastructure by acting as an antioxidant and reducing OS during various degrees of cellular insults, which needs to be further explored. [ABSTRACT FROM AUTHOR]

Ti and their alloys are commonly used metallic implants due to their good bio-activity. Post-surgery reflects inferior osseointegration that makes the material unhealthy in the long run after surgery. In this regard, surface characteristic remains one of the most trivial and incurable problems for hard tissue application. In the present study, Nano-Dicalcium Phosphate Dihydrate (DCPD) Coatings were deposited over anodized TiO 2 Nanotubes and its structural, surface and in-vitro study has been done. Surface transitions from the contact angle analyser reveal hydrophilic to super-hydrophilic surfaces have been achieved over Ti6Al4V alloy. The highest absorbance value has been observed on TTOAD compared to TD in both 24 h and 48 h. FESEM Mapping and EDS unveil that the distribution of elements is not homogenous entirely. However, the AFM result reveals that the distribution of an ex-situ deposited layer is enriched in Calcium-Phosphorus elements and has distinct irregular topography. Besides more surface roughness value has been revealed in TTOAD surface. Optical density (O.D.) value at 570 nm with ∼ 1.09 O.D. at 24 h and ∼1.3 O.D. at 48 h was obtained on the TTOAD specimen reflecting the best cell proliferation of MG-63 compared to TD. In addition, superhydrophilicity with ∼8.5° contact angle was gained at TTOAD compared to TD and TTOCD specimens. [ABSTRACT FROM AUTHOR]

Pure and Sn-doped hierarchical ZnO based 1D single-crystalline nanorods were produced by chemical vapour transport and condensation process in Ar/O 2 atmosphere. Conventional analytical techniques, such as field emission scanning electron microscopy (FESEM), X-ray diffraction, transmission electron microscopy, photoluminescence spectra and high angle annular dark field image (HAADF) of the as-grown nanostructures confirm tin doping in ZnO single crystals. A possible formation mechanism of the nanostructures was proposed. It was established that the incorporation of Sn in the ZnO branched nanorods significantly improves their sensitivity towards acetone and ethanol vapours. The response and recovery times were measured to be ~7 s and ~38 s when exposed to 50 ppm acetone at the test temperature of 400 °C. The acetone and ethanol sensing performance of the doped ZnO nanorod sensors were better than that undoped ZnO nanostructured sensors under comparable operating conditions. The sensitivity/response of acetone and ethanol vapours for Sn-doped hierarchical ZnO nanorod was ascribed to the single-crystalline morphology, increased O-vacancy and other defect density and higher surface areas, which in turn accelerates a fast and effective diffusion process for acetone or ethanol vapours as compared to undoped ZnO nanostructures. [ABSTRACT FROM AUTHOR]

In an equiatomic CrCuFeNiZn multicomponent alloy, fine powders of nanocrystalline Y 2 O 3 (1 wt %) is dispersed and mechanically alloyed (MA) by high energy ball milling technique. The phase analysis by X-ray Diffraction (XRD) reveals that milling for about 30 h leads to the formation of 'FCC' and 'BCC' as stable phases in addition to minor amount of YZn 5 intermetallic phase with hexagonal crystal structure in the aggregate. The crystallite size as measured from the XRD analysis for the 30 h milled powder was found to be 17.2 nm and it well agrees with that observed in Transmission electron microscope (TEM) analysis. SEM-EDS analysis further confirms the homogeneous distribution of the constituting elements in the as-fabricated alloy aggregate. The present investigation offers a roadmap for using yttria doped CrCuFeNiZn multicomponent alloy as a potential candidate material used as core components in nuclear reactors. • Synthesized the novel Y 2 O 3 dispersed CrCuFeNiZn nanocrystalline multicomponent alloy through mechanical alloying process. • Phase evolution and effect of Y 2 O 3 addition has been studied during mechanical alloying process. • There was no significance effect of Y 2 O 3 on the CrCuFeNiZn nanocrystalline multicomponent phase evolution. [ABSTRACT FROM AUTHOR]

Today's environment is polluted by heavy metal ions and toxic substances. The lead (Pb2+) is one of them which affect the environment by both natural and anthropogenic ways. Protection of the environment needs proper determination and quantification of these metal ions. Thus developing proper sensor with less cost is the focus of present research. Electrochemical sensor has attracted a great attention to determine these hazardous elements. In the present work sensor modified by blast furnace slag (BFS), provides a new opportunity for enhancing the electrocatalytic performance of fabricated sensor. The BFS was characterized by SEM, XRD, BET and particle size analyzer. Moreover different compositions of BFS were use to optimize the slag ratio. Furthermore the sensor modified material characterized by CV, Chronocoulometry, EIS and DPV. The electrochemical response towards Pb2+ on BFS modified sensor was explored by CV, EIS and DPV. Transfer coefficient (α) was calculated as 0.664 and rate constant (K s) 1.08 s−1. The electrode was linear in the concentration range of 1–5 μM (R 2 = 0.99). Experimental parameter like pulse height, step height, pH were also optimized. Detection and quantification limits were calculated as 0.015 μM and 0.053 μM respectively. This detection limit for Pb2+ is lower than the permissible limit provided by W.H.O. for drinking water. The electrode shows high sensitivity of 1068 μA/μM−1 cm-2 for Pb2+ ions with superior reproducibility and repeatability. The results suggested that blast furnace slag was a better material for heavy metal ion in aqueous solutions. [ABSTRACT FROM AUTHOR]

In this work, the effect of Mo addition on phase evolution and mechanical properties of as-cast FeCoNiCuMo x (molar ratio X = 0.2, 0.4, 0.6, 0.8, 1) high entropy alloy systems (HEAs) have been investigated. It has been found that with increasing Mo concentration, atomic size difference (δ), geometrical parameter (∧) and enthalpy of mixing (ΔH mix) of this multi-component alloy systems decrease. However, the mixing entropy (ΔS mix), electronegativity difference (ΔX), d-orbital energy level parameter ( M d ‾), root mean square residual strain (RMS) and critical parameter (Ω) increases which clearly indicates the formation of the solid solution with no intermetallic compounds. X-ray diffraction and scanning electron microscope analysis also confirm that FCC solid solution phases are formed at X = 0.2 to 0.6. Further, on increasing the Mo concentration beyond 13 at % (X > 0.6), FCC1 and FCC2 phase were detected due to large positive enthalpy of mixing between Cu and others (Fe, Co, Ni, and Mo) elements. Moreover, the segregation of Cu in the FeCoNiCuMo x (X = 0.8 and 1) alloy can be well predicted via φ and λ parameters. The Compressive strength and hardness were found to increase with Mo concentration in FeCoNiCuMo x HEAs due to solid solution strengthening. • Synthesized the novel FeCoNiCuMo x HEAs via Vacuum arc melting and suction casting. • Phase evolution has been studied and correlate with thermodynamic criterion with segregation parameter. • A novel Mo based high entropy alloy exhibit good compressive strength and ductility. [ABSTRACT FROM AUTHOR]