Complete Dehydrogenation of Hydrazine Borane on Manganese Oxide Nanorod-Supported Ni@Ir Core-Shell Nanoparticles.

Hydrazine borane (HB; N2H4BH3) has been considered to be one of the most promising solid chemical hydrogen storage materials owing to its high hydrogen capacity and stability under ambient conditions. Despite that, the high purity of hydrogen production from the complete dehydrogenation of HB stands as a major problem that needs to be solved for the convenient use of HB in on-demand hydrogen production systems. In this study, we describe the development of a new catalytic material comprised of bimetallic Ni@Ir core-shell nanoparticles (NPs) supported on OMS-2-type manganese oxide octahedral molecular sieve nanorods (Ni@Ir/OMS-2), which can reproducibly be prepared by following a synthesis protocol including (i) the oleylamine-mediated preparation of colloidal Ni@Ir NPs and (ii) wet impregnation of these ex situ synthesized Ni@Ir NPs onto the OMS-2 surface. The characterization of Ni@Ir/OMS-2 has been done by using various spectroscopic and visualization techniques, and their results have revealed the formation of well-dispersed Ni@Ir core-shell NPs on the surface of OMS-2. The catalytic employment of Ni@Ir/OMS-2 in the dehydrogenation of HB showed that Ni0.22@Ir0.78/OMS-2 exhibited high dehydrogenation selectivity (>99%) at complete conversion with a turnover frequency (TOF) value of 2590 h-1 at 323 K, which is the highest activity value among all reported catalysts for the complete dehydrogenation of HB. Furthermore, the Ni0.22@Ir0.78/OMS-2 catalyst enables facile recovery and high stability against agglomeration and leaching, which make it a reusable catalyst in the complete dehydrogenation of HB. The studies reported herein also include the collection of wealthy kinetic data to determine the activation parameters for Ni0.22@Ir0.78/OMS-2-catalyzed dehydrogenation of HB.

Advances in nanomaterial based optical biosensing and bioimaging of apoptosis via caspase-3 activity: a review.

Caspase-3 plays a vital role in intrinsic and extrinsic pathways of programed cell death and in cell proliferation. Its detection is an important tool for early detection of some cancers and apoptosis-related diseases, and for monitoring the efficacy of pharmaceuticals and of chemo- and radiotherapy of cancers. This review (with 72 references) summarizes nanomaterial based methods for signal amplification in optical methods for the determination of caspase-3 activity. Following an introduction into the field, a first large section covers optical assays, with subsections on luminescent and chemiluminescence, fluorometric (including FRET based), and colorimetric assays. Further section summarize methods for bioimaging of caspase-3. A concluding section covers current challenges and future perspectives. Graphical Abstract ᅟ.

Inhibition effects of isoproterenol, chlorpromazine, carbamazepine, tamoxifen drugs on glutathione S-transferase, cholinesterases enzymes and molecular docking studies.

Nowadays, inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and glutathione S-transferases (GSTs) have been a very crucial issue for pharmacological treatments of several disasters. Herein, we investigated inhibition effects of Tamoxifen (TAM), Isoprenaline (ISO), Chlorpromazines (CPZ) and Carbamazepine (CBZ) on GST, AChE, BChE and then molecular structures and active sides of the tested drugs by molecular docking process. The enzyme activity results showed that nearly the whole tested drugs inhibited GST, BChE, AChE efficiently. Chlorpromazine was found to be the best inhibitor for the GST enzyme and the Ki value of this drug was found to be 42.83 ± 8.52 nM. Besides, Isoproterenol drug with the Ki value of 51.80 ± 9.44 nM was found to be the most effective inhibitor on the AChE enzyme. Molecular docking studies showed that the receptor-binding sites of GST, AChE, and BChE were found to 1.069, 1.090, and 1.15 of Sitecore and 0.992, 1.113, and 1.217 of Dscore, respectively. The method was validated by doing validation studies and these validations revealed that re-docked ligands located a very closed position with co-crystallized ligand into the active site for all receptors. Calculation studies for determining the possible enzyme inhibition mechanism with the used drugs revealed that amino and aromatic ring in the structure of the drugs used are effective in inhibition reactions.Communicated by Ramaswamy H. Sarma.

Development of a reliable microRNA based electrochemical genosensor for monitoring of miR-146a, as key regulatory agent of neurodegenerative disease.

A MicroRNA (miR) based electrochemical method for quantification of miR-146a, a known biomarker for neurodegenerative disease, was developed. In this bioassay, the capture microRNA (C-miR) was self-assembled on the gold surface and used for quantification of target microRNA (T-miR) of miR-146a. For this purpose, an optimized concentration of C-miR was immobilized on the surface of gold electrode and used for capture of target analyte (T-miR). All of preparation steps were characterized by electrochemical techniques (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)) and atomic force microscopy (AFM). At the optimized conditions, the linear dynamic range, limit of quantification and relative standard deviation of the proposed bioassay were obtained as 10 pM to 1 µM, 10 pM and 1.59%, respectively. The unprocessed human serum sample was used as a real sample and the results fully confirm that the designed microRNA based biosensor is capable for detection of miR-146a as neurodegenerative disease biomarker. The developed method offers a more precise and high sensitive tool to be used in clinical applications for early detection of neurodegenerative disease like Alzheimer's and Parkinson.