Chitosan grafted butein: A metal-free transducer for electrochemical genosensing of exosomal CD24.

Metal-free cost-efficient biocompatible molecules are beneficial for opto-electrochemical bioassays. Herein, chitosan (CS) conjugated butein is prepared via graft polymerization. Structural integrity between radical active sites of CS and its probable conjugation routes with reactive OH group of butein during grafting were comprehensively studied using optical absorbance/emission property, NMR, FT-IR and XPS analysis. Fluorescence emission of CS-conjugated butein (CSB) was studied in dried flaky state as well as in drop casted form. Cyclic voltammetric study of CSB modified glassy carbon electrode exhibits 2e-/2H+ transfer reaction in phosphate buffered saline electrolyte following a surface-confined process with a correlation coefficient of 0.99. Unlike pristine butein, CSB modified electrode display a highly reversible redox behavior under various pH ranging from 4 to 9. For the proof-of-concept CSB-modified flexible screen printed electrodes were processed for electrochemical biosensing of exosomal CD24 specific nucleic acid at an ultralow sample concentration, promising for ovarian cancer diagnosis.

In Situ Decorated Ni Metallic Layer with CoS2-Layered Thin Films via a Layer-by-Layer Strategy Using Pulsed Laser Deposition for Enhanced Electrocatalytic OER.

The catalytic activity of 3d-transition-metal-based electrocatalysts has exhibited considerable enhancements in electrocatalytic water splitting via pioneering modulations in the active sites. To overcome the energy loss because of the mechanic steps involved in a complex oxygen evolution reaction (OER), the electrode surface with only a few layers would be an advantage over multilayers for the ease of the electrolyte interaction and gas evolution. Here, for the first time, thin films of CoS2 are prepared on a carbon cloth via a pulsed laser deposition (PLD) technique via layer-by-layer deposition of Ni that tend to give Ni-CoS2 thin films. Based on varying the ablation of metallic Ni followed by CoS2 as a layer-by-layer assembly using PLD, three catalysts, namely, Ni5-CoS2, Ni10-CoS2, and Ni15-CoS2, were prepared. In OER, to achieve a benchmarking current density of 10 mA cm-2 in 1 M KOH, Ni10-CoS2 required a lesser overpotential of 304 mV, whereas others, namely, Ni5-CoS2, Ni15-CoS2, and CoS2, required overpotentials of 328, 336, and 373 mV, respectively, to attain the same current density. The charge transfer kinetics associated with all of the catalysts were analyzed, and the corresponding Tafel slope values for Ni5-CoS2 and Ni10-CoS2 were 75 and 98 mV/dec, respectively, ensuring the facile transfer of electrons at the interface. The assistance of metallic Ni sites also ensured stability for long-term applications. These findings will give a way for other earth-abundant catalysts for the increased electrocatalytic activity toward energy needs in future.

Magnetron sputtered magnesium-based thin film metallic glasses for bioimplants.

Mg-based thin film metallic glasses (TFMGs) can viably decrease stress shielding caused by mismatch of the modulus of elasticity between the implant material and human bone. Here, Mg-based TFMGs were fabricated onto implantable substrates by ion assisted pulsed DC magnetron sputtering. The microstructure assessment and the impact of the principle constituents of the coatings were determined utilizing an x-ray diffractometer, a transmission electron microscope, and x-ray photoelectron spectroscopy. The hardness of these thin films was estimated to be 5.1 GPa. In vitro degradation tests including electrochemical studies and immersion tests in simulated body fluid revealed that the presence of zinc could raise the corrosion resistance of Mg-based TFMG. Indirect in vitro cytotoxicity using L929 fibroblast cells revealed that the TFMGs did not induce any toxicity in cells. Biomineralization experiments using Saos-2 cells promoted the formation of calcium phosphate on its surface.

Fabrication of Gd2O3 Nanosheet-Modified Glassy Carbon Electrode for Nonenzymatic Highly Selective Electrochemical Detection of Vitamin B2.

A novel Gd2O3 nanosheet was synthesized by the template-free chemical coprecipitation method. Interestingly, upon calcination at 600 °C, nanoparticles were transformed into a nanosheet, as observed from field emission scanning electron microscopy (FESEM) images. An increase in the calcination temperature to 600 °C increases the particle size to 50 nm, which results in aggregation. A sheetlike Gd2O3 exhibits superparamagnetism from 300 K. The highly selective nonenzymatic sensing of riboflavin (RF) was studied using a modified glassy carbon electrode with Gd2O3 nanosheets, and its various applications were made possible by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The redox behavior of the RF was determined. The newly fabricated sensor showed high sensitivity, stability, and reproducibility and was also tested with a commercial vitamin B2 tablet and a milk powder sample.

Effect of selected dehulled legume incorporation on functional and nutritional properties of protein enriched sorghum and wheat extrudates.

The effect of legume incorporation (5%, 10% and 15%) on functional and nutritional properties of sorghum and wheat extrudates was investigated. Sorghum extrudates incorporated with legumes showed lower water absorption index water solubility index and pasting properties viz., peak viscosity, minimum viscosity, breakdown viscosity, final viscosity and total set back and similar degree of gelatinization and nutritional profile. At 15% incorporation level, water absorption index and water solubility index found to be maximum while degree of gelatinization and all the pasting properties showed lowest values for both sorghum and wheat extrudates. Similarly nutritional profile observed to be significantly higher for 15% as compared to 10% and 15% incorporation levels. Incorporation of legumes at 15% could be effective in producing high energy dense food products having better functional and nutritional properties.