Multi-targeted molecular docking,drug-likeness and ADMET studies of derivatives of few quinoline- and acridine-based FDA-approved drugs for anti-breast cancer activity

Structural Chemistry - Quinoline- and acridine-based drugs are widely used as anti-breast cancer agents. These drugs act through various mechanisms of action; for example, neratinib acts on...     

Eco-friendly synthesis of ZnO nanorods using Cycas pschannae plant extract with excellent photocatalytic,antioxidant, and anticancer nanomedicine for lung cancer treatment

The tunable ZnO nanorods (NRs) are produced due to the phytochemicals present in Cycas pschannae leaves which act as reducing and stabilizing agents. The confirmations of the ZnO NRs were validated using different characterization techniques: X-ray diffraction, Fourier transform infrared spectroscopy, Brunauer, Emmett and Teller (BET), scanning electron microscopy–Energy Dispersive X-Ray Analysis (EDX), UV–visible spectroscopy, Raman spectroscopy, and transmission electron microscopy. The ZnO NRs show unique surface area and low particle size. Photocatalytic activity was measured and found to be 50.75% at low concentrations and 78.33% at high concentrations. The antioxidant activity of the ZnO NRs also showed promising results for their use in free radical scavenging. In vitro toxicity studies using zebrafish embryos was performed to evaluate the toxic nature of it and the obtained result confirmed its non-toxic nature. In addition, ZnO anticancer potential was verified using the A549 lung cancer cell line. Cytotoxic assessments of ZnO NRs were performed via 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), and neutral red uptake assays to examine the cell death cycle on the A549 lung cancer cell. Dose-dependent apoptosis and necrosis were confirmed by Lactate dehydrogenase (LDH) assay. It was also confirmed that ZnO NRs induce Reactive oxygen species (ROS) and apoptosis inside cancer (A549) cells via different intrinsic gene expression. Thus, based on this research it is evident that an effective ecofriendly, nontoxic potential anticancer drug can be synthesized using C. pschannae leaf extract.     

Nanotechnology for Electroanalytical Biosensors of Reactive Oxygen and Nitrogen Species

Over the past several decades, nanotechnology has contributed to the progress of biomedicine, biomarker discovery, and the development of highly sensitive electroanalytical / electrochemical biosensors for in vitro and in vivo monitoring, and quantification of oxidative and nitrosative stress markers like reactive oxygen species (ROS) and reactive nitrogen species (RNS). A major source of ROS and RNS is oxidative stress in cells, which can cause many human diseases, including cancer. Therefore, the detection of local concentrations of ROS (e. g. superoxide anion radical; O₂^•−) and RNS (e. g. nitric oxide radical; NO^• and its metabolites) released from biological systems is increasingly important and needs a sophisticated detection strategy to monitor ROS and RNS in vitro and in vivo. In this review, we discuss the nanomaterials‐based ROS and RNS biosensors utilizing electrochemical techniques with emphasis on their biomedical applications.     

Exploring Network Formation of Tough and Biocompatible Thiol‐yne Based Photopolymers

This work deals with the in‐depth investigation of thiol‐yne based network formation and its effect on thermomechanical properties and impact strength. The results show that the bifunctional alkyne monomer di(but‐1‐yne‐4‐yl)carbonate ( DBC ) provides significantly lower cytotoxicity than the comparable acrylate, 1,4‐butanediol diacrylate ( BDA ). Real‐time near infrared photorheology measurements reveal that gel formation is shifted to higher conversions for DBC /thiol resins leading to lower shrinkage stress and higher overall monomer conversion than BDA . Glass transition temperature (T_g), shrinkage stress, as well as network density determined by double quantum solid state NMR, increase proportionally with the thiol functionality. Most importantly, highly cross‐linked DBC /dipentaerythritol hexa(3‐mercaptopropionate) networks (T_g ≈ 61 °C) provide a 5.3 times higher impact strength than BDA , which is explained by the unique network homogeneity of thiol‐yne photopolymers.

     

Cooperativity and cluster growth patterns in acetonitrile: A DFT study

Cooperativity in intermolecular interactions and cluster growth patterns of acetonitrile has been studied using M06L density functional theory. Cyclic, ladder‐type, stacked, cross‐stacked, and mixed patterns are studied. Total interaction energy (E_int) and interaction energy per monomer (E_m) show maximum stability and cooperativity in stacked clusters followed by cross‐stacked ones. As cluster size increased, magnitude of E_m showed significant increase. Compared to E_m of dimer (?2.97 kcal/mol), the increase is 2.6‐fold for 27mer . Higher stabilization in larger clusters is attributed to strong cooperativity in intermolecular C? H···N and dipolar interactions. Enhanced cooperativity in stacked structures is supported by atoms‐in‐molecule electron density (ρ) data. Sum of ρ at intermolecular bond critical points is the highest for stacked clusters. Further, area of negative‐valued molecular electrostatic potential is linearly related with E_int and showed the lowest value in stacked followed by cross‐stacked clusters, indicating maximum utilization of lone pair density and maximum cooperativity in such growth patterns. A red shift in the average C? N stretching frequencies with increase in the number of monomers and its direct correlation with E_int in stacked clusters also supported their stability. Further, two known crystal patterns of acetonitrile (α and β) with 16 monomers are optimized and compared with the most stable hexadecamer pattern and are found to show lower values for E_int and E_m compared to the latter. Based on this result, we predict the existence of a third crystal pattern for acetonitrile which will be more ordered and more stable than α and β forms. © 2014 Wiley Periodicals, Inc.     

Formation of Peracetic Acid upon Aging of Perborate in Acetic Acid. Kinetics of the Oxidation of S-Phenylmercaptoacetic Acids

 Upon aging, perborate in glacial acetic acid generates peracetic acid and thus oxidizes S-phenylmercaptoacetic acid rapidly. Perborate dissolved in ethylene glycol, however, does not show the aging effect, and the corresponding oxidation proceeds smoothly. The oxidation is of second order and not acid catalyzed. Boric acid and borate do not influence the oxidation. In the smooth oxidation, is the reactive species. The oxidation of some para-substituted S-phenylmercaptoacetic acids conforms to the Exner relationship, indicating operation of a common mechanism. Also, the oxidation obeys the Hammett equation with a negative reaction constant. However, the oxidation of p-nitro-S-phenylmercaptoacetic acid follows a different kinetic pathway.