Parthenium hysterophorus derived nanostructures as an efficient carbocatalyst for the electrochemical sensing of mercury(II) ions.

The sustainable utilization of resources motivate us to create eco-friendly processes for synthesizing novel carbon nanomaterials from waste biomass by minimizing chemical usage and reducing energy demands. By keeping sustainability as a prime focus in the present work, we have made the effective management of Parthenium weeds by converting them into carbon-based nanomaterial through hydrothermal treatment followed by heating in a tube furnace under the nitrogen atmosphere. The XPS studies confirm the natural presence of nitrogen and oxygen-containing functional groups in the biomass-derived carbon. The nanostructure has adopted a layered two-dimensional structure, clearly indicated through HRTEM images. Further, the nanomaterials are analyzed for their ability towards the electrochemical detection of mercury, with a detection limit of 6.17 µM, while the limit of quantification and sensitivity was found to be 18.7 µM and 0.4723 µM µA-1 cm-2, respectively. The obtained two-dimensional architecture has increased the surface area, while the nitrogen and oxygen functional groups act as an active site for sensing the mercury ions. This study will open a new door for developing metal-free catalysts through a green and sustainable approach by recycling and utilization of waste biomass.

Comparative Drug Release Investigations for Diclofenac Sodium Drug (DS) by Chitosan-Based Grafted and Crosslinked Copolymers.

The hydrogels responding to pH synthesized by graft copolymerization only and then concurrent grafting and crosslinking of monomer N-isopropyl acrylamide (NIPAAM) and binary comonomers acrylamide, acrylic acid and acrylonitrile (AAm, AA and AN) onto chitosan support were explored for the percent upload and release study for anti-inflammatory diclofenac sodium drug (DS), w.r.t. time and pH. Diclofenac sodium DS was seized in polymeric matrices by the equilibration process. The crosslinked-graft copolymers showed the highest percent uptake than graft copolymers (without crosslinker) and chitosan itself. The sustainable release of the loaded drug was studied with respect to time at pH 2.2, 7.0, 7.4 and 9.4. Among graft copolymers (without crosslinking), Chit-g-polymer (NIPAAM-co-AA) and Chit-g-polymer (NIPAAM-co-AN) exhibited worthy results for sustainable drug deliverance, whereas Crosslink-Chit-g-polymer (NIPAAM-co-AA) and Crosslink-Chit-g-polymer (NIPAAM-co-AAm) presented the best results for controlled/sustained release of diclofenac sodium DS with 93.86 % and 96.30 % percent release, respectively, in 6 h contact time. Therefore, the grafted and the crosslinked graft copolymers of the chitosan showed excellent delivery devices for the DS with sustainable/prolonged release in response to pH. Drug release kinetics was studied using Fick's law. The kinetic study revealed that polymeric matrices showed the value of n as n > 1.0, hence drug release took place by non-Fickian diffusion. Hence, the present novel findings showed the multidirectional drug release rate. The morphological changes due to interwoven network structure of the crosslinked are evident by the Scanning electron microscopy (SEM) analysis.

Preparation and characterization of pH-responsive guar gum microspheres.

Guar gum, being the natural polymer is renewable, nontoxic, biocompatible and biodegradable. Therefore, it is the perfect material to formulate particulates or microspheres for potential applications in pharmaceutical. The formulation of material in nano/microsphere scale offers new rich in application potential. In view of that, novel biodegradable and pH-sensitive hydrogels composed of pH-sensitive methacrylic acid (MAc) and a biodegradable guar gum were synthesized by grafting reactions. Water-in-oil (w/o) emulsion method was used to direct the pH-sensitive material in microspheres shape using bi-functional glutaraldehyde (GA) as crosslinker. The synthesized microspheres were characterized by FTIR and SEM (different magnification). The swelling ratios of hydrogels in buffer solutions showed a pH-dependent profile at physiological pH. In vitro release data was analyzed using Fick's law, which indicated swelling controlled super case II transport of BSA through the synthesized microspheres. Therefore, in conclusion, as ascertained from the results the introduction of -COOH moieties along the guar gum chain drastically increases the end-use performance due to pH-sensitivity.

Uneven spread of cis- and trans-editing aminoacyl-tRNA synthetase domains within translational compartments of P. falciparum.

Accuracy of aminoacylation is dependent on maintaining fidelity during attachment of amino acids to cognate tRNAs. Cis- and trans-editing protein factors impose quality control during protein translation, and 8 of 36 Plasmodium falciparum aminoacyl-tRNA synthetase (aaRS) assemblies contain canonical putative editing modules. Based on expression and localization profiles of these 8 aaRSs, we propose an asymmetric distribution between the parasite cytoplasm and its apicoplast of putative editing-domain containing aaRSs. We also show that the single copy alanyl- and threonyl-tRNA synthetases are dually targeted to parasite cytoplasm and apicoplast. This bipolar presence of two unique synthetases presents opportunity for inhibitor targeting their aminoacylation and editing activities in twin parasite compartments. We used this approach to identify specific inhibitors against the alanyl- and threonyl-tRNA synthetases. Further development of such inhibitors may lead to anti-parasitics which simultaneously block protein translation in two key parasite organelles, a strategy of wider applicability for pathogen control.