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Chemo-photothermal therapy has attracted extensive research attention because of its synergistic effect in destroying cancer cells, which makes it one of the most effective treatments. Gold nanorods conjugated with thiolated beta-cyclodextrin loaded with doxorubicin (DOX), AuNRs@S-β-CD-DOX nanocomposite, for intracellular delivery were designed to enhance therapeutic efficacy and improve toxicity of gold nanorods. The UV–vis absorption spectra of the AuNRs@S-β-CD nanocomposite showed strong absorption in the NIR region (biological window), making it a promising candidate for both photothermal therapy and chemotherapy. With such a combined chemo-photothermal effect, the viability of A549 lung cancer cells in vitro is anticipated to be significantly reduced making it a promising biomedical material for cancer treatment. The results show good photothermal efficiency of gold nanorods, high loading capacity for DOX, and biocompatibility of the AuNRs@S-β-CD-DOX nanocomposite.

Essential oils (EOs) have drawn growing attention due to an increased risk of chemical contamination upon the application of synthetic fungicides to post-harvest fruits. This experiment investigated the antifungal activity of seven EOs at different concentrations of 0.5, 1, 2, 4, 6, 8, and 10 μL mL−1against the fungus Botrytis cinereain two methods of liquid and vapor phase. Besides the chemical analysis of the EOs by GC–MS, minimum fungicidal concentration, minimum inhibitory concentration, and the release of cellular material were investigated. The dominant compound in rosemary EO is camphene (33.8%), whereas 1–8 cineole (67.61%) was found to be most abundant in Eucalyptus. Cumin contained cumin aldehyde (27.14%), peppermint EO contained menthol (28.27%), and the most common compound in tarragon EO was methyl chavicol (78.74%). Limonene (63.27%) was the predominant compound in lemon EO. The highest percentage of compounds in savory EO was carvacrol (50.33). The results showed that the vapor phase was consistently more effective in fungal growth than the liquid phase effect. Savory and peppermint EOs were very influential on the growth of B. cinereaat relatively low concentrations due to the presence of dominant compounds such as menthol (28.27%) and carvacrol (50.34%). According to the comparison of the data on inhibition percentage with the control group, there was a significant enhancement in the entire liquid and vapor phases by increasing EO concentration. Generally, factors such as plant species, application method, and concentration affect EOs antifungal activity. It is concluded that the EO mechanism against B. cinereamight be due to its effect on cell membrane permeability according to the electrolytes’ leakage. Therefore, these EOs as natural antimicrobial compounds seem to be effective in preventing gray mold contamination instead of synthetic preservatives, which have several established adverse effects.

We designed a new unique amphoteric monodisperse colloid with a large complex internal structure, in which silica surfaces are bridged with an organic cross-linker. The rationale was that such colloids would be excellent adsorbents for cationic and anionic dyes and, when doped with noble metal nanoparticles, would be an excellent catalyst for the reduction of a variety of organic compounds. In the first step, the organo-silica bridging agent (bivalent organic cross-linkers) DABCO-S (silanated DABCO) was prepared through a simple nucleophilic substitution reaction between (3-chloropropyl)triethoxysilane and bivalent 1,4-diazabicyclo[2.2.2]octane (DABCO) (a strong base). In the second step, a DABCO-S bridge was introduced into dendritic fibrous nanostructured colloidal silica (DFNS) under open-vessel reflux conditions. We refer to the product obtained by incorporating DABCO-S in DFNS as DDS. The unique characteristics of DFNS are completely preserved in this new type of periodic mesoporous organo-silica–DFNS. The produced nanocomposite has a high surface area of about 807 m2g–1, a large pore volume of 1.9 cm3g–1, and a bimodal pore size distribution, with small 2.5 nm pores and large 30 nm pores. As such, DDS is an efficient adsorbent for dye removal from wastewater. The results show that DDS can adsorb positive and negative dyes such as methylene blue, orange II sodium salt (OR), and procion red mx-58 (PR) with a capacity of 678, 3192, and 3190 mg dye/g adsorbent. Introducing silver nanoparticles in situinto DDS leads to a composite with excellent accessibility of reactants to the Ag surface, resulting in an efficient catalytic reduction of nitro aromatic compounds (NACs) in aqueous media.

In this study, a new type of silica-cellulose hybrid aerogel was synthesized through a green and facile chemical cross-linking process. In a first step, dendritic fibrous nanostructured (colloidal) silica particles (DFNS) were prepared by a simple hydrothermal technique. Then, the surface of DFNS particles was functionalized with amine groups using 3-aminopropyltriethoxysilane to produce DFNS-NH2. In a second step, bifunctional hairy nanocellulose (BHNC) particles were functionalized with both aldehyde and carboxylic groups. The aldehyde groups of BHNC and the amine groups of DFNS-NH2chemically reacted through a Schiff base reaction to form a hybrid hydrogel nanocomposite. Therefore, no external cross-linker is required in the synthesis. This hybrid aerogel is very lightweight and highly porous with a density of 0.107 g mL–1and a porosity of 93.0 ± 0.4%. It has a large surface area of 350 m2g–1, a large pore volume of 0.23 cm3g–1, and a small pore size of 3.9 nm. The developed aerogel contains both positively and negatively charged functional groups and is a highly efficient substrate for dye adsorption from water, for both cationic and anionic organic dyes. These aerogels were found to have an outstanding adsorption capacity toward methylene blue (MB) as a cationic dye and methyl orange (MO) as an anionic dye. The results show that the aerogels can adsorb MB and MO with a capacity of 270 and 300 mg dye/g adsorbent, respectively.

Nanoparticles have properties that can be fine-tuned by their size as well as shape. Hence, there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed aggregates. This letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica gel. The combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH4efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous medium. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid groups. The silver particles immobilized on silica gel are stable in the presence of oxygen for several months.

For the first time, metal hydrogen sulfates and phosphates/silica gel have been studied as efficient and powerful solid acid catalysts in the ring opening of epoxides with thiocyanate anion. The most significant result was obtained by Al(HSO4)3/SiO2 which afforded the corresponding β-hydroxy thiocyanates under mild reaction conditions and in very short reaction times. The cheapness, availability of the catalyst, ease of procedure and work-up make this method attractive for the organic synthesis.

A highly effective and mild protocol for ring opening of epoxides with NH4SCN in the presence of catalytic amount of a multi-site phase-transfer catalyst, α,α′,α″-N-hexakis(triethylammoniummethylene chloride)-melamine, is developed. A variety of β-hydroxy thiocyanates as important intermediates in agricultural and pharmaceutical chemistry were obtained in high yields with excellent regioselectivity and in short reaction times.

A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide (TBAB) as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification.

Sodium borohydride supported on alumina reduces imines to the corresponding secondary amines in high to excellent isolated yields under solvent-free conditions. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen, nitro, and cyano groups.

In the last few decades, production of alternative fuels has been a global concern among the environmental scientists in view of scarcity of fossil fuels and increasing global warming. Biodiesels are being synthesized as green fuel by transesterification of different oils and fats over diverse synthetically developed novel heterogeneous catalysts. In this present work,a magnetically reusable hybrid nanocatalyst of basic nature has been designed for the production of biodiesels by transesterification of waste corn oil and rapeseed oil in presence of methanol. During the synthesis of catalyst, magnetic CuFe2O4nanoparticles were amalgamated with graphene oxide (GO) by using pistachio leaf extract and subsequently MgO nanoparticles were impregnated over it. The catalyst was physicochemically characterized by FT-IR, SEM, TEM, EDX, elemental mapping, XRD, VSM and TGA studies. The reaction parameters like reaction time, the methanol/oil molar ratio and the catalyst loading were optimized through Response Surface Methodology (RSM) using Box-Behnken experimental design. In addition, the catalysts was magnetically retrieved quite easily and reused five times in succession without considerable loss in its reactivity in the transesterification reaction.

7 examples

Thiocyanohydrins are efficiently and regioselectively obtained by ring opening of epoxide under solvent‐free conditions using the solid acid catalyst melamine sulfonic acid.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.