In Vitro Evaluation of Biological Activities of Silver Nanoparticles Synthesized Using Dalbergia rostrata Stem Bark

Silver nanoparticles (AgNPs) synthesized are utilized in drugs because of their pharmacological and biomedical applications and also due to their ecofriendly properties. In the present study, stable AgNPs have been synthesized from the aqueous extract of Dalbergia rostrata stem bark (DRSB), which is used both as a reducing and as a stabilizing agent. The AgNPs synthesized by ultrasonication at 25°C for 10 min were found to be stable in aqueous solution at room temperature over a period of 3 months. The quantitatively stable AgNPs formed by treating the aqueous solution of AgNO3 with the aqueous extract of the plant by reduction of Ag+ ions when monitored by UV–visible spectroscopic study revealed the surface plasmon resonance (SPR) at 425 nm. According to transmission electron micrography, the NPs were spherical and in the size range of 14 ± 4 nm. When evaluated for their anti-inflammatory and antioxidant activity by in vitro methods, AgNPs showed considerably enhanced activity compared to DRSB aqueous extract.

Ball Mill–assisted Preparation of Nano-CaCO3 as a Novel and Green Catalyst–based Eggshell Waste

Ball mill–assisted preparation of nano-bio Calcite (CaCO3) based on avian shell and its application as a novel, biodegradable, and heterogeneous catalyst with high catalytic activity and reusability in the green and high efficient synthesis of pyrano[4,3- b]pyrans via a condensation reaction of different aromatic aldehydes, malononitrile, and 4-hydroxy-6-methyl-2 H-pyran-2-one at 120°C under solvent-free conditions is reported. The reaction proceeds to completion within 5–30 min in 90–98% yield. The nanocatalyst was characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscope (SEM), elemental analysis, and laser particle sizer.

A Green Approach

We have attempted a green alternative to reuse the spent fluid catalytic cracking (FCC) catalyst that is used in petroleum refining industry for the upgradation and purification of various petroleum streams and residues. The spent FCC zeolite–based catalyst modified by enhancing the acidic properties by incorporating Zn and In metals in the matrix. The various prepared catalysts were systematically characterized by X-ray powder diffraction and Brunauer–Emmett–Teller (BET; adsorption isotherm) surface area. The acidity of the materials was studied by temperature-programmed desorption of ammonia (NH3-TPD). The well-characterized catalysts were applied for liquid phase benzylation of o-xylene using benzyl chloride.

Crystal Structure of Pyridoxal Amino Methyl Phosphonic Acid (PYRAMPA) and Its Stability Constants with Al3+

The crystal structure of the newly synthesized ligand pyridoxal amino methyl phosphonic acid (PYRAMPA) from green materials in deionized water and methanol is presented. It took only two steps to prepare this new ligand. The ligands’ stability constants with Al3+ are also reported in aqueous solutions at 25 °C ± 0.1 °C. The ligand was introduced as part of our concerted efforts to identify and synthesize an orally effective aluminum sequestering agent due to the known toxic effect of aluminum in living organisms particularly humans. PYRAMPA is a multidentate ligand suitable to sequester aluminum with very high stability.

One-pot Three-component Synthesis of β-amino Carbonyl Compounds Using Nanocrystalline Solid Acid Catalyst

This study presents a simple highly versatile and efficient synthesis of various β-amino carbonyl compounds in the Mannich reaction of acetophenone with aromatic aldehydes and aromatic amines in the presence of nanosulfated zirconia, nanostructured ZnO, nano-γ-alumina, and nano-ZSM-5 zeolites as the catalyst in ethanol at moderate temperature. The optical properties of the nanostructured organic molecules were studied. The advantages of methods are short reaction times, milder conditions, easy workup, and purification of products by nonchromatographic methods. The catalysts can be recovered for the subsequent reactions and reused without any appreciable loss of efficiency.

Iodine Doping Studies on Nonannealed Perylene 3,4,9,10-Tetra Carboxylic Dianhydride/Cobalt Phthalocyanine Bulk Heterojunction Solar Cells

Perylene 3,4,9,10-tetra carboxylic dianhydride (PTCDA) thin films find a lot of optoelectronic applications. In this work, thin films of PTCDA were deposited using vacuum evaporation technique onto clean glass substrates and the variation in conductivity, optical bandgap and percentage transmission due to iodine doping for different time intervals are discussed. To study the doping effects on devices, organic solar cells based on cobalt phthalocyanine (CoPc)/PTCDA as active layers on indium tin oxide–coated glass substrates were fabricated and characterized to evaluate the solar cell parameters. It was found that doping with iodine considerably increases the power conversion efficiency of the solar cells.

Medical Use of Nanoparticles

Researchers today are able to encapsulate medicine in nanoparticles, the size of viruses. The nanoparticles are effective for drug delivery—the delivery of the medicine to the body—because they can very precisely find diseased cells and carry the medicine to them. This means that one can suffice with less dosage and thereby fewer side effects. In addition, nanoscience and nanotechnological methods are spurring the development of more sophisticated tools for detecting diseases, such as cancer and atherosclerosis, at early stages and performing neurosurgery. Applications of nanotechnology in disease diagnoses are developing rapidly. Their unique size-dependent properties make these materials superior and indispensable in many areas of human activity.

Green Nanotechnology from Brassicaceae

The interaction of cocktail of phytochemicals from broccoli with gold salt results in dual reduction and surface capping to produce well-defined stable and biocompatible gold nanoparticles (B-AuNPs). Broccoli phytochemicals–coated gold nanoparticles (B-AuNPs) have been fully characterized. Detailed in vitro stability in various biological fluids and affinity and selectivity for tumor cells have been investigated. The B-AuNPs showed significant in vitro cytotoxic effects against various cancer cells (MDA-MB-231, PC-3, U266, SkBr3, and T47D) as confirmed by 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) and flow cytometry apoptosis assays. Surface encapsulation of cocktail of broccoli phytochemicals on AuNPs facilitates the cellular internalization, thereby validating the in vitro therapeutic effects of these nanoparticles. Detailed analyses performed by combination of gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS) have confirmed the presence of biologically active phytochemicals including glucoraphanin, phenethyl glucosinolates, quercetin, folic acid, vitamin C, allyl isothiocyanates, 2-phenylethyl isothiocyanates, and sulforaphane. The unique synergistic cocktail effects of B-AuNPs will provide new opportunities for generating biocompatible AuNPs for molecular imaging and therapeutic applications.

Application of Nanosols in Textile Industry

Inorganic metal oxide nanoparticles are mainly synthesized by sol–gel process. The most important beneficial advantage of mentioned process is facile and the time-consuming route. The resultant meta-stable synthesized inorganic nanoparticles can easily modify different substrates and alter their performance. The presented review investigates the possible applications of nanosols (especially silica and titanium dioxide sols) in the field of textile industry, including the formation of hydrophobic, bioactive or protective metallic oxide coatings on textiles by physical or chemical modifying of nanosols.

A Simple, Rapid, and Green Synthesis of Capped Gold Nanospheres and Nanorods Using Aqueous Extract of Azolla

In the last few decades, an increasing commercial demand for metal nanoparticles is found due to their numerous applications in various fields such as electronics, catalysis in organic synthesis, material chemistry, energy, and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, wherein the chemicals used are quite harmful and flammable. Herein, we reported a cheap and environment-friendly procedure for the synthesis of capped gold nanoparticles of different shapes from aqueous solution of tetrachloroauric acid (HAuCl4) using aqueous extract of Azolla pinnata, blue-green algae used as a reducing as well as capping agent. The so-prepared gold nanoparticles were well characterized by UV-visible spectroscopy, transmission electron microscopy (TEM), and quasi-elastic light scattering (QELS) techniques. The TEM showed nearly uniform distribution of the particles in water, which is again confirmed by QELS. This is for the first time that aqueous extract of A. pinnata was used for the synthesis of gold nanoparticles.