Kuvempu University

About: Kuvempu University is a education organization based out in Shimoga, India. It is known for research contribution in the topics: Cyclic voltammetry & Carbon paste electrode. The organization has 1575 authors who have published 2210 publications receiving 39755 citations. The organization is also known as: KU.

Highly porous, honeycomb like Ag–ZnO nanomaterials for enhanced photocatalytic and photoluminescence studies: green synthesis using Azadirachta indica gum

Abstract: The preparation of zinc oxide and silver doped zinc oxide nanoparticles using zinc nitrates and silver nitrates as oxidizers and Azadirachta indica gum as a fuel via solution combustion method at 500 °C. The synthesized nanoparticles were characterized by XRD, FTIR, UV-DRS, SEM and TEM studies; these materials were tested for photoluminescence and photocatalytic activity studies. The PXRD data indicated that the synthesized nanoparticles confirmed as hexagonal phase with average crystallite size of 13.33 and 13.34 nm for ZnO and Ag–ZnO respectively. The SEM data revealed that, the material obtained is highly porous and honeycomb like structure. In the photocatalytic degradation of methylene blue, Ag–ZnO nanoparticles have shown the good photocatalytic activity than undoped ZnO nanoparticles. This is due to the presence of Ag on the surface of ZnO catalyst makes the catalyst more sensitive to light and reduce the electron hole recombination. Furthermore, we have also examined the photoluminescence studies for the synthesized materials and it has given the green emission by excitation at 380 nm. In this study, the green synthesis method will produces large quantity of nanomaterials with less time and low cost.

Carmine and fast green as corrosion inhibitors for mild steel in hydrochloric acid solution

Abstract: The inhibition action of carmine and fast green dyes on corrosion of mild steel in 0.5 M HCl was investigated using mass loss, polarization and electrochemical impedance (EIS) methods at 300 K. The inhibition efficiency was found to increase with increasing concentration of the inhibitors. The inhibition efficiency of fast green (%η - 98) is higher than that of carmine (%η - 92) and found to be maximum in 1 × 10-3 M solution. The inhibitors act as mixed type with predominant cathodic effect. The inhibitors were adsorbed on the mild steel surface according to the Temkin adsorption isotherm. The surface morphology of the mild steel specimens was evaluated using SEM images.

Hypocholesterolemic and hepatoprotective effects of flaxseed chutney: Evidence from animal studies.

Abstract: Rats fed with hypercholesterolemic diet showed a significant increase in serum total—cholesterol, liver homogenate total-cholesterol, HDL-cholesterol and changed LDL-cholesterol, and HDL/LDL ratio in comparison to control. Flaxseedchutney (FC) supplemented diet (15%, w/w) was found to be more effective in restoring lipid profile changes in rats fed with cholesterol, (1.0%). The activities of serum marker enzymes glutamate oxaloacetate transminase (GOT), glutamate pyruvate transaminase (GPT) and alkaline phosphatase (ALP) were elevated significantly in carbon tetrachloride induced rats. Administration of flaxseedchutney (15%, w/w) resulted in depletion of serum marker enzymes and exhibited recoupment thus showing significant hepatoprotective effect. It was observed that flaxseedchutney supplemented diet could lower the serum cholesterol and as a potential source of antioxidants it could exert protection against hepatotoxic damage induced by carbon tetrachloride (CCl4) in rats.

Development of a simple bioelectrode for the electrochemical detection of hydrogen peroxide using Pichia pastoris catalase immobilized on gold nanoparticle nanotubes and polythiophene hybrid

Abstract: In this paper, a simple and innovative electrochemical hydrogen peroxide biosensor has been proposed using catalase (CATpp) derived from Pichia pastoris as bioelectrocatalyst. The model biocomponent was immobilized on gold nanoparticle nanotubes (AuNPNTs) and polythiophene composite using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide and N-hydroxysuccinimide (EDC–NHS) coupling reagent. In this present work, we have successfully synthesized gold nanoparticles (AuNPs) by ultrasonic irradiation. The tubular gold nanostructures containing coalesced AuNPs were obtained by sacrificial template synthesis. The assembly of AuNPNTs onto the graphite (Gr) electrode was achieved via S–Au chemisorption. The latter was pre-coated with electropolymerized thiophene (PTh) to enable S groups to bind AuNPNTs. The combination of AuNPNTs–PTh, i.e., an inorganic–organic hybrid, provides a stable enzyme immobilization platform. The physical morphology of the fabricated biosensor Gr/PTh/AuNPNTs/EDC–NHS/CATpp was investigated using scanning electron microscopy and energy-dispersive microscopy. The analytical performance of the bioelectrode was examined using cyclic voltammetry, differential pulse voltammetry and chronoamperometry. Operational parameters such as working potential, pH, and thermal stability of the modified electrode were examined. The beneficial analytical characteristics of the proposed electrode were demonstrated. Our results indicate that the Gr/PTh/AuNPNTs/EDC–NHS/CATpp bioelectrode exhibits a wide linear range from 0.05 mM to 18.5 mM of H2O2, fast response time of 7 s, excellent sensitivity of 26.2 mA mM−1 cm−2, good detection limit of 0.12 μM and good Michaelis–Menten constant of 1.4 mM. In addition, the bioelectrode displayed good repeatability, high stability and acceptable reproducibility, which can be attributed to the AuNPNTs–PTh composite that provides a biocompatible micro-environment.