Front Cover: Metal Nano Networks by Potential‐Controlled In Situ Assembling of Gold/Silver Nanoparticles (ChemistryOpen 12/2019)

There is a serious need to develop and test new biodegradable packaging which could at least partially replace petroleum-based materials. Therefore, the objective of this work was to examine the influence of the recently developed furcellaran nanocomposite film with silver nanoparticles (obtained by an in situ method) on the quality properties of two cheese varieties: a rennet-curd (gouda) and an acid-curd (quark) cheese. The water content, physicochemical properties, microbiological and organoleptic quality of cheese, and migration of silver nanoparticles were examined. Both the number of Lactococcus and total bacteria count did not differ during storage of gouda regardless of the packaging applied. The number of Lactococcus decreased in analogous quark samples. The use of the film slowed down and inhibited the growth of yeast in gouda and quark, respectively. An inhibitory effect of this film on mold count was also observed; however, only regarding gouda. The level of silver migration was found to be lower in quark than in gouda. The film improved the microbiological quality of cheeses during storage. Consequently, it is worth continuing research for the improvement of this film in order to enable its use in everyday life.

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In-situ cellulose-framework templates mediated monodispersed silver nanoparticles via facile UV-light photocatalytic activity for anti-microbial functionalization

Carbohydrate Polymers ◽

10.1016/j.carbpol.2021.118255 ◽

2021 ◽

pp. 118255

Author(s):

Sung Won Ko ◽

Ji Yeon Lee ◽

Abdelrahman I. Rezk ◽

Chan Hee Park ◽

Cheol Sang Kim

Keyword(s):

Silver Nanoparticles ◽

Photocatalytic Activity ◽

Uv Light

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Apoferritin Amyloid-Fibril Directed the In Situ Assembly and/or Synthesis of Optical and Magnetic Nanoparticles

Nanomaterials ◽

10.3390/nano11010146 ◽

2021 ◽

Vol 11 (1) ◽

pp. 146

Author(s):

Rocío Jurado ◽

Natividad Gálvez

Keyword(s):

Metal Binding ◽

Amyloid Fibrils ◽

Magnetic Iron Oxide Nanoparticles ◽

Synthetic Strategy ◽

In Vivo Detection ◽

Inorganic Species ◽

Gold Silver ◽

Β Lactoglobulin

The coupling of proteins that can assemble, recognise or mineralise specific inorganic species is a promising strategy for the synthesis of nanoscale materials with a controllable morphology and functionality. Herein, we report that apoferritin protein amyloid fibrils (APO) have the ability to assemble and/or synthesise various metal and metal compound nanoparticles (NPs). As such, we prepared metal NP–protein hybrid bioconjugates with improved optical and magnetic properties by coupling diverse gold (AuNPs) and magnetic iron oxide nanoparticles (MNPs) to apoferritin amyloid fibrils and compared them to the well-known β-lactoglobulin (BLG) protein. In a second approach, we used of solvent-exposed metal-binding residues in APO amyloid fibrils as nanoreactors for the in situ synthesis of gold, silver (AgNPs) and palladium nanoparticles (PdNPs). Our results demonstrate, the versatile nature of the APO biotemplate and its high potential for preparing functional hybrid bionanomaterials. Specifically, the use of apoferritin fibrils as vectors to integrate magnetic MNPs or AuNPs is a promising synthetic strategy for the preparation of specific contrast agents for early in vivo detection using various bioimaging techniques.

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Facile Preparation of Mesoporous MCM-48 Containing Silver Nanoparticles with Fly Ash as Raw Materials for CO Catalytic Oxidation

Micromachines ◽

10.3390/mi12070841 ◽

2021 ◽

Vol 12 (7) ◽

pp. 841

Author(s):

Dong Tian ◽

Yonghong Chen ◽

Xiaoyong Lu ◽

Yihan Ling ◽

Bin Lin

Keyword(s):

Silver Nanoparticles ◽

Fly Ash ◽

Co Oxidation ◽

Surface Composition ◽

Raw Materials ◽

Silica Source ◽

Co Conversion ◽

Co Catalytic Oxidation ◽

Adsorption Desorption

An environmentally friendly method was proposed to prepare mesoporous Mobil Composition of Matter No.48 (MCM-48) using fly ash as the silica source. Silver nanoparticles were infiltrated on MCM-48 facilely by an in situ post-reduction method and evaluated as an effective catalyst for CO oxidation. The as-prepared MCM-48 and Ag/MCM-48 nanoparticles were characterized by XRD, N2 adsorption/desorption, and TEM. Investigations by means of XPS for Ag/MCM-48 were performed in order to illuminate the surface composition of the samples. Studies revealed the strong influence of the loading of Ag nanoparticles on catalysts in the oxidation of CO. CO conversion values for Ag/MCM-48 of 10% and 100% were achieved at temperatures of 220 °C and 270 °C, respectively, indicating that the Ag-decorated MCM-48 catalyst is extremely active for CO oxidation.

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