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Nanoparticle Tracking Analysis of Gold Nanoparticles in Aqueous Media through an Inter-Laboratory Comparison

In the field of nanotechnology, analytical characterization plays a vital role in understanding the behavior and toxicity of nanomaterials (NMs). ...

uv-vis-spectroscopic-characterization-nanomaterials-aqueous

UV-Vis Spectroscopic Characterization of Nanomaterials in Aqueous Media

The physicochemical characterization of nanomaterials (NMs) is often an analytical challenge, due to their small size (at least one dimension in the ...

University of Birmingham

Due to the increasing use and production of nanomaterials (NMs), the ability to characterise their physical/chemical properties quickly and reliably has never been so important. Proper characterisation allows a thorough understanding of the material and its stability, and is critical to establishing dose-response curves to ascertain risks to human and environmental health. Traditionally, methods such as Transmission Electron Microscopy (TEM), Field Flow Fractionation (FFF) and Dynamic Light Scattering (DLS) have been favoured for size characterisation, due to their wide-availability and well-established protocols. Capillary Electrophoresis (CE) offers a faster and more cost-effective solution for complex dispersions including polydisperse or non-spherical NMs. CE has been used to rapidly separate NMs of varying sizes, shapes, surface modifications and compositions. This review will discuss the literature surrounding the CE separation techniques, detection and NM characteristics used for the analysis of a wide range of NMs. The potential of combining CE with mass spectrometry (CE-MS) will also be explored to further expand the characterisation of NMs, including the layer of biomolecules adsorbed to the surface of NMs in biological or environmental compartments, termed the acquired biomolecule corona. CE offers the opportunity to uncover new/poorly characterised low abundance and polar protein classes due to the high ionisation efficiency of CE-MS. Furthermore, the possibility of using CE-MS to characterise the poorly researched small molecule interactions within the NM corona is discussed.

Current Application of Capillary Electrophoresis in Nanomaterial Characterisation and Its Potential to Characterise the Protein and Small Molecule Corona.

During their lifecycle, many engineered nanoparticles (ENPs) undergo significant transformations that may modify their toxicity, behaviour, and fate in the environment. Therefore, understanding the possible environmentally relevant transformations that ENPs may undergo as a result of their surroundings is becoming increasingly important. This work considers industrially produced ceria (CeO) and focuses on a particle library consisting of seven zirconium-doped variants (CeZrO) where the Zr doping range is x = 0-1. The study assesses their potential transformation in the presence of environmentally relevant concentrations of phosphate. These ENPs have an important role in the operation of automotive catalysts and therefore may end up in the environment where transformations can take place. Samples were exposed to pH adjusted (c. 5.5) solutions made up of either 1 mM or 5 mM each of KHPO, citric acid and ascorbic acid and the transformed particles were characterised by means of DLS - size and zeta potential, UV/VIS, TEM, FT-IR, EDX and XRD. Exposure to the phosphate solutions resulted in chemical and physical changes in all ceria-containing samples to cerium phosphate (with the monazite structure). The transformations were dependent on time, ceria concentration in the particles (Ce:Zr ratio) and phosphate to ceria ratio. The presence of Zr within the doped samples did not inhibit these transformations, yet the pure end member ZrO ENPs showed no conversion to phosphate. The quite dramatic changes in size, structure and composition observed raise important questions regarding the relevant form of the materials to investigate in ecotoxicity tests, and for regulations based on one or more dimensions in the nanoscale.

Physical and chemical transformations of zirconium doped ceria nanoparticles in the presence of phosphate: Increasing realism in environmental fate and behaviour experiments.

Chronic wounds are often recalcitrant to treatment because of high microbial bioburden and the problem of microbial resistance. Silver is a broad-spectrum natural antimicrobial agent with wide applications extending to proprietary wound dressings. Recently, silver nanoparticles have attracted attention in wound management. In the current study, the green synthesis of nanoparticles was accomplished using a natural reducing agent, curcumin, which is a natural polyphenolic compound that is well-known as a wound-healing agent. The hydrophobicity of curcumin was overcome by its microencapsulation in cyclodextrins. This study demonstrates the production, characterization of silver nanoparticles using aqueous curcumin:hydroxypropyl-β-cyclodextrin complex and loading them into bacterial cellulose hydrogel with moist wound-healing properties. These silver nanoparticle-loaded bacterial cellulose hydrogels were characterized for wound-management applications. In addition to high cytocompatibility, these novel dressings exhibited antimicrobial activity against three common wound-infecting pathogenic microbes , , and .

Sophie M. Briffa

School of Geography,
Earth and Environmental Sciences,
School of Geography, Earth and Environmental Sciences

University of Birmingham

Nanoparticle Tracking Analysis of Gold Nanoparticles in Aqueous Media through an Inter-Laboratory Comparison

UV-Vis Spectroscopic Characterization of Nanomaterials in Aqueous Media

Sophie M. Briffa

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}School of Geography,Earth and Environmental Sciences,School of Geography, Earth and Environmental Sciences

University of Birmingham

Nanoparticle Tracking Analysis of Gold Nanoparticles in Aqueous Media through an Inter-Laboratory Comparison

UV-Vis Spectroscopic Characterization of Nanomaterials in Aqueous Media

School of Geography,
Earth and Environmental Sciences,
School of Geography, Earth and Environmental Sciences