Polyvinylpyrrolidone, PVP, stabilized Pd–M (M
=
Ag, Au, Cu, Ni and Pt) alloy colloids are successfully prepared by γ-irradiation in aqueous solution. PVP-stabilized Pd–M colloids are characterized by ...field-emission transmission electron microscopy (FE-TEM) and energy dispersive X-ray spectroscopy (EDXS). The catalytic efficiency of Pd and Pd–M alloy colloids is analyzed for the reduction of 4-nitrophenol in aqueous solution at room temperature. The catalytic efficiency of Pd–M alloy nanoparticles takes the following order: Pd
>
Pd–Cu
∼
Pd–Ni
>
Pd–Ag
∼
Pd–Au
>
Pd–Pt.
Functional and engineered colloids fabricated from edible materials have recently gained a lot of interest for futuristic applications in the field of foods for purposes ranging from microstructure ...development to delivery of health‐promoting bioactives to manipulation of food–body interactions. This review tackles a very ambitious task of discussing the current understanding of functional colloids within the framework of foods. Physicochemical attributes of several novel complex colloids fabricated from natural, and often, underutilized edible materials are clearly and comprehensively reviewed in this paper. This review not only provides a scientific insight into the advances made in the field of colloid‐based food structuring but also touches on the exciting future opportunities in this promising multidisciplinary field.
A comprehensive account of functional and engineered colloids (derived from a wide range of edible materials) with respect to their fabrication, properties, and emerging applications in food product design is provided herein. Topics discussed include advanced delivery of health‐promoting components, manipulation of food–body interactions, and food structuring.
Helmuth Möhwald (1946–2018) von Klitzing, Regine; Zemb, Thomas N.
Angewandte Chemie International Edition,
August 13, 2018, Letnik:
57, Številka:
33
Journal Article
Recenzirano
Helmuth Möhwald, Founding Director of the Max Planck Institute for Colloids and Interfaces, Potsdam–Golm, passed away on March 27, 2018, at the age of 72. Möhwald's scientific achievements included ...the development of the layer‐by‐layer (LbL) technique to prepare ultrathin organized organic films, and its application in the coating of colloidal particles.
The use of flow field flow fractionation (FlFFF) for the separation and characterization of natural colloids and nanoparticles has increased in the last few decades. More recently, it has become a ...popular method for the characterization of manufactured nanoparticles. Unlike conventional filtration methods, FlFFF provides a continuous and high-resolution separation of nanoparticles as a function of their diffusion coefficient, hence the interest for use in determining particle size distribution. Moreover, when coupled to other detectors such as inductively coupled plasma-mass spectroscopy, light scattering, UV-absorbance, fluorescence, transmission electron microscopy, and atomic force microscopy, FlFFF provides a wealth of information on particle properties including, size, shape, structural parameters, chemical composition and particle-contaminant association. This paper will critically review the application of FlFFF for the characterization of natural colloids and natural and manufactured nanoparticles. Emphasis will be given to the detection systems that can be used to characterize the nanoparticles eluted from the FlFFF system, the obtained information and advantages and limitation of FlFFF compared to other fractionation and particle sizing techniques. This review will help users understand (i) the theoretical principles and experimental consideration of the FlFFF, (ii) the range of analytical tools that can be used to further characterize the nanoparticles after fractionation by FlFFF, (iii) how FlFFF results are compared to other analytical techniques and (iv) the range of applications of FlFFF for natural and manufactured NPs.
Small molecule effectors are essential for drug discovery. Specific molecular recognition, reversible binding and dose-dependency are usually key requirements to ensure utility of a novel chemical ...entity. However, artefactual frequent-hitter and assay interference compounds may divert lead optimization and screening programmes towards attrition-prone chemical matter. Colloidal aggregates are the prime source of false positive readouts, either through protein sequestration or protein-scaffold mimicry. Nevertheless, assessment of colloidal aggregation remains somewhat overlooked and under-appreciated. In this Review, we discuss the impact of aggregation in drug discovery by analysing select examples from the literature and publicly-available datasets. We also examine and comment on technologies used to experimentally identify these potentially problematic entities. We focus on evidence-based computational filters and machine learning algorithms that may be swiftly deployed to flag chemical matter and mitigate the impact of aggregates in discovery programmes. We highlight the tools that can be used to scrutinize libraries, and identify and eliminate these problematic compounds.
MoS2 is a two-dimensional material that is gaining prominence due to its unique electronic and chemical properties. Here, we demonstrate ligand conjugation of chemically exfoliated MoS2 using thiol ...chemistry. With this method, we modulate the ζ-potential and colloidal stability of MoS2 sheets through ligand designs, thus enabling its usage as a selective artificial protein receptor for β-galactosidase. The facile thiol functionalization route opens the door for surface modifications of solution processable MoS2 sheets.
The ability to design and assemble three-dimensional structures from colloidal particles is limited by the absence of specific directional bonds. As a result, complex or low-coordination structures, ...common in atomic and molecular systems, are rare in the colloidal domain. Here we demonstrate a general method for creating the colloidal analogues of atoms with valence: colloidal particles with chemically distinct surface patches that imitate hybridized atomic orbitals, including sp, sp(2), sp(3), sp(3)d, sp(3)d(2) and sp(3)d(3). Functionalized with DNA with single-stranded sticky ends, patches on different particles can form highly directional bonds through programmable, specific and reversible DNA hybridization. These features allow the particles to self-assemble into 'colloidal molecules' with triangular, tetrahedral and other bonding symmetries, and should also give access to a rich variety of new microstructured colloidal materials.
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