Insights into the binding interaction between copper ferrite nanoparticles and bovine serum albumin: An effect on protein conformation and activity.

The binding affinity between bovine serum albumin (BSA) and copper ferrite (CuFe2 O4 ) nanoparticles in terms of conformation, stability and activity of protein was studied using various spectroscopic methods. The quenching involved in BSA-CuFe2 O4 NP interaction was static quenching as analysed by different techniques (steady-state and time-resolved fluorescence along with temperature-dependent fluorescence measurements). Among all types of possible interactions, it was revealed that the major binding forces were van der Waals interaction and hydrogen bonding, which were explored from negative values of enthalpy change (∆H = -193.85 kJ mol-1 ) and entropy change (∆S = -588.88 J mol-1  K-1 ). Additionally, synchronous, circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy measurements confirmed the conformational changes in BSA upon the addition of CuFe2 O4 NP. Furthermore, thermal denaturation observations were consistent with the circular dichroism results. The interaction of CuFe2 O4 NP with BSA decreased the esterase activity in the BSA assay, revealing the affinity of copper ferrite towards the active site of BSA.

Greener Route for Synthesis of aryl and alkyl-14H-dibenzo [a.j] xanthenes using Graphene Oxide-Copper Ferrite Nanocomposite as a Recyclable Heterogeneous Catalyst.

A facile, efficient and environmentally-friendly protocol for the synthesis of xanthenes by graphene oxide based nanocomposite (GO-CuFe2O4) has been developed by one-pot condensation route. The nanocomposite was designed by decorating copper ferrite nanoparticles on graphene oxide (GO) surface via a solution combustion route without the use of template. The as-synthesized GO-CuFe2O4 composite was comprehensively characterized by XRD, FTIR, Raman, SEM, EDX, HRTEM with EDS mapping, XPS, N2 adsorption-desorption and ICP-OES techniques. This nanocomposite was then used in an operationally simple, cost effective, efficient and environmentally benign synthesis of 14H-dibenzo xanthene under solvent free condition. The present approach offers several advantages such as short reaction times, high yields, easy purification, a cleaner reaction, ease of recovery and reusability of the catalyst by a magnetic field. Based upon various controlled reaction results, a possible mechanism for xanthene synthesis over GO-CuFe2O4 catalyst was proposed. The superior catalytic activity of the GO-CuFe2O4 nanocomposite can be attributed to the synergistic interaction between GO and CuFe2O4 nanoparticles, high surface area and presence of small sized CuFe2O4 NPs. This versatile GO-CuFe2O4 nanocomposite synthesized via combustion method holds great promise for applications in wide range of industrially important catalytic reactions.

Investigation of titania nanoparticles on behaviour and mechanosensory organ of Drosophila melanogaster.

Titania nanoparticles are used in food, cosmetic, medicine, paint and many more domestic items. Its extensive use has raised the threat to the physiological system and thus the functioning of the body. In the current study, the toxicity of TiO2 is checked by adding it in food and using Drosophila melanogaster as a model organism. Various concentrations of TiO2 (50, 100, 200, 250mg·L-1) toxicity was assessed via oral route exposure. Survivability, life-cycle, mechanosensory behaviour and structure of various mechanosensory organs were monitored as a read out of nanoparticle toxicity. TiO2 NPs generate reactive oxygen species which can modify multiple signalling pathways and thus can alter the development and behavioural pattern of the fly.

1-Methylimidazole stabilization of gold nanoparticles in imidazolium ionic liquids.

Low levels of 1-methylimidazole additives have been found to have dramatic effects on the resulting stability of gold and bimetallic nanoparticles in ionic liquids (ILs).