Synthesis of Silver Glyconanoparticles from New Sugar-Based Amphiphiles and Their Catalytic Application

Abstract

Oligosaccharide-based amphiphiles were readily prepared by click chemistry from ω-azido-hexanoic or dodecanoic acids with propargyl-functionalized maltoheptaose or xyloglucanoligosaccharides. These amphiphilic compounds were used as capping/stabilizer agents in order to obtain highly stable catalytic silver glyconanoparticles (Ag-GNPs) through the in situ reduction of silver nitrate with NaBH4. With a view to long-term storage, the stabilization was optimized using a multivariate approach, and the nanoparticles were characterized by UV-vis, TEM, SAXS, and DLS. In order to explore the functionality of the Ag-GNPs in catalysis, a full kinetic analysis of the reduction of p-nitrophenol by NaBH4 in water and in water/ethanol mixtures was performed under semi-heterogeneous and quasi-homogeneous conditions. A pseudomonomolecular surface reaction was performed, and the kinetic data obtained were treated according to the Langmuir model. The Ag-GNPs were very active, and both substrates adsorbed onto the surface of the nanoparticles. For comparison purposes, the reaction was also performed in the presence of silver-sodium dodecanoate nanoparticles, which showed catalytic activity similar to that of the glyconanoparticles, supporting the choice of the carboxyl group as the stabilizing agent, although it provided much lower temporal stability. Finally, by combining kinetic and water/ethanol surface tension data it was possible to observe the effect of the addition of the less polar solvent (ethanol) to the reaction medium.

Facile synthesis of PtSnZn nanosheet thin film at oil–water interface by use of organometallic complexes: An efficient catalyst for methanol oxidation and p‐nitrophenol reduction reactions

“…Various heterogeneous catalysts of Pd, Pt, Ag and Au nanomaterials have been utilized for p ‐Nip reduction, but these are unselective and costly. Alloying is a strategy that has been used to develop catalysts of noble metals that are effective and less expensive.…”

Green synthesis of silver nanoparticles by Ferulago macrocarpa flowers extract and their antibacterial, antifungal and toxic effects

“…The formed NPs showed a sharp absorption peak at around 429 nm specific for SNPs. The sharp peak demonstrates spherical shape SNP synthesis [20]. The color and absorbance of the solution did not change after this time.…”

“…Thus, there is a growing interest to develop fast, economical and ecofriendly procedures to nanoparticle synthesis. In recent years, the biosynthesis of NPs using natural resources including microorganisms, plant extracts, polymers, sugars and enzymes as reductants and capping agents has been achieved (17)(18)(19)(20). Biosynthesis of NPs has many advantages over other methods.…”

A sustainable, top-down mechanosynthesis of carbohydrate-functionalized silver nanoparticles

“…A typically adopted protocol relies upon thiol-functionalized sugars, 47 but other choices are possible. Eising et al 48 used carbohydrate-based amphiphiles grafted to Ag NPs by carboxyl groups, while several different functional groups like amines and amides have been used in place of thiols. 49 A positive answer to question a) can be given taking into account that also underivatized carbohydrates, linked to Ag NPs by weaker non-covalent interactions like physisorption, 50 may successfully act as capping agents for Ag NPs.…”