Metal-containing Nanoparticles Research Articles

High-Resolution Characterization of Coal Combustion-Derived Metal-Containing Nanoparticles and Their Health-Related Implications

High-Resolution Characterization of Coal Combustion-Derived Metal-Containing Nanoparticles and Their Health-Related Implications

An Unprecedented Metal Distribution in Silica Nanoparticles Determined by Single-Particle Inductively Coupled Plasma Mass Spectrometry.

Metal-containing nanoparticles are now common in applications ranging from catalysts to biomarkers. However, little research has focused on per-particle metal content in multicomponent nanoparticles. In this work, we used single-particle inductively coupled plasma mass spectrometry (ICP-MS) to determine the per-particle metal content of silica nanoparticles doped with tris(2,2'-bipyridyl)ruthenium(II). Monodispersed silica nanoparticles with varied Ru doping levels were prepared using a water-in-oil microemulsion method. These nanoparticles were characterized using common bulk-sample methods such as absorbance spectroscopy and conventional ICP-MS, and also with single-particle ICP-MS. The results showed that averaged concentrations of metal dopant measured per-particle by single-particle ICP-MS were consistent with the bulk-sample methods over a wide range of dopant levels. However, the per-particle amount of metal varied greatly and did not adhere to the usual Gaussian distribution encountered with one-component nanoparticles, such as gold or silver. Instead, the amount of metal dopant per silica particle showed an unexpected geometric distribution regardless of the prepared doping levels. The results indicate that an unusual metal dispersal mechanism is taking place during the microemulsion synthesis, and they challenge a common assumption that doped silica nanoparticles have the same metal content as the average measured by bulk-sample methods.

Gold Nanoclusters Synthesized within Single-Chain Nanoparticles as Catalytic Nanoreactors in Water.

Metalloenzymes are able to catalyze complex biochemical reactions in cellular (aqueous) media with high efficiency. In recent years, a variety of metal-containing single-chain nanoparticles (SCNPs) have been synthesized as simplified metalloenzyme-mimetic nano-objects. However, most of the metal-containing SCNPs reported so far contained complexed metal ions but not metal nanoclusters (NCs) with diameter <5 nm, which could be used as powerful, emerging catalysts. Herein, we report the synthesis of gold nanoclusters (Au-NCs) within SCNPs and the further use of Au-NCs/SCNPs as catalytic nanoreactors in water. We demonstrate that a common motif contained in several drugs (i.e., the aminophenyl-oxazolidinone fragment present in Rivaroxaban, Sutezolid, and Linezolid) can be efficiently prepared in water from a hydrophobic precursor compound by using the Au-NCs/SCNPs as efficient catalytic nanoreactors. In summary, this work paves the way forthe synthesis of metal-NCs/SCNPs for advanced catalysis in aqueous media.

Imaging of Subcellular Distribution of Platinum in Single Cells Using Laser Ablation Inductively Coupled Plasma Mass Spectrometry.

Laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) is a well-established and sensitive analytical technique, which provides high-resolution imaging of endogenous elements, element tagged-markers, metal-containing nanoparticles, and metallodrugs within cells. Here we describe a protocol for imaging the subcellular distribution of platinum within A549 cells, following their incubation with the platinum-based anticancer agent, Oxaliplatin. We outline the essential steps in sample preparation and instrumental setup and discuss how the current generation of low-dispersion instruments facilitates new approaches to data acquisition and image processing. The protocol described herein can be easily adapted for other cell lines and metal-containing labeling agents.

DNA-functionalized metal or metal-containing nanoparticles for biological applications.

The conjugation of DNA molecules with metal or metal-containing nanoparticles (M/MC NPs) has resulted in a number of new hybrid materials, enabling a diverse range of novel biological applications in nanomaterial assembly, biosensor development, and drug/gene delivery. In such materials, the molecular recognition, gene therapeutic, and structure-directing functions of DNA molecules are coupled with M/MC NPs. In turn, the M/MC NPs have optical, catalytic, pore structure, or photodynamic/photothermal properties, which are beneficial for sensing, theranostic, and drug loading applications. This review focuses on the different DNA functionalization protocols available for M/MC NPs, including gold NPs, upconversion NPs, metal-organic frameworks, metal oxide NPs and quantum dots. The biological applications of DNA-functionalized M/MC NPs in the treatment or diagnosis of cancers are discussed in detail.

The elemental fingerprint as a potential tool for tracking the fate of real-life model nanoplastics generated from plastic consumer products in environmental systems.

Metals and metalloids are widely used in producing plastic materials as fillers and pigments, which can be used to track the environmental fate of real-life nanoplastics in environmental and biological systems. Therefore, this study investigated the metal and metalloids concentrations and fingerprint in real-life model nanoplastics generated from new plastic products (NPP) and from environmentally aged ocean plastic fragments (NPO) using single particle-inductively coupled plasma-mass spectrometry (SP-ICP-TOF-MS) and transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (TEM-EDX). The new plastic products include polypropylene straws (PPS), polyethylene terephthalate bottles (PETEB), white low-density polyethylene bags (LDPEB), and polystyrene foam shipping material (PSF). All real-life model nanoplastics contained metal and metalloids, including Si, Al, Sr, Ti, Fe, Ba, Cu, Pb, Zn, Cd, and Cr, and were depleted in rare earth elements. Nanoplastics generated from the white LDPEB were rich in Ti-bearing particles, whereas those generated from PSF were rich in Cr, Ti, and Pb. The Ti/Fe in the LDPEB nanoplastics and the Cr/Fe in the PSF nanoplastics were higher than the corresponding ratios in natural soil nanoparticles (NNPs). The Si/Al ratio in the PSF nanoplastics was higher than in the NNPs, possibly due to silica-based fillers. The elemental ratio of Si/Al, Fe/Cr, and Fe/Ni in the nanoplastics derived from ocean plastic fragments was intermediate between the nanoplastics derived from real-life plastic products and NNPs, indicating a combined contribution from pigments and fillers used in plastics and from natural sources. This study provides a method to track real-life nanoplastics in controlled laboratory studies based on nanoplastic elemental fingerprints. It expands the realm of nanoplastics that can be followed based on their metallic signatures to all kinds of nanoplastics. Additionally, this study illustrates the importance of nanoplastics as a source of metals and metal-containing nanoparticles in the environment.

Single particle inductively coupled plasma mass spectrometry and its variations for the analysis of nanoparticles.

Single particle inductively coupled plasma mass spectrometry (spICPMS) can count and weigh metal-containing nanoparticles (NPs), enabling their sizing if their geometry, density, and composition are known. With a nebulizer and a spray chamber for sample introduction, both the sample uptake rate and the transport efficiency must be determined when calibrating with solutions. In contrast, flow injection (FI) and mono-segmented flow analysis (MSFA) coupled to spICPMS do not need determination of the transport efficiency and sample uptake rate for accurate NP mass measurement. Correcting for the significant settling time on some instruments is also discussed, as well as calibration through signal integration instead of averaging, which eliminates the need to measure the transport efficiency when seeking NP mass. Nitrogen added to the outer plasma gas can reduce the background for the determination of P, S, Ca and Fe. Infrared heating of the sample introduction system provides 100% transport efficiency, enabling accurate particle mass and concentration measurements without measurement of transport efficiency.

Spectral and Near-Field Scattering Characteristics of Two-Layered Metal-Containing Nanoparticles in Absorbing Matrices

Spectral and Near-Field Scattering Characteristics of Two-Layered Metal-Containing Nanoparticles in Absorbing Matrices

Charge Shielding-Oriented Design of Zinc-Based Nanoparticle Liquids for Controlled Nanofabrication.

Metal-containing nanoparticles possess nanoscale sizes, but the exploitation of their nanofeatures in nanofabrication processes remains challenging. Herein, we report the realization of a class of zinc-based nanoparticle liquids and their potential for applications in controlled nanofabrication. Utilizing the metal-core charge shielding strategy, we prepared nanoparticles that display glass-to-liquid transition behavior with glass transition temperature far below room temperature (down to -50.9 °C). Theoretical calculations suggest the outer surface of these unusual nanoparticles is almost neutral, thus leading to interparticle interactions weak enough to give them liquefaction characteristics. Such features endow them with extraordinarily high dispersibility and excellent film-forming capabilities. Twenty-two types of nanoparticles synthesized by this strategy have all shown good lithographic properties in the mid-ultraviolet, electron beam, or extreme ultraviolet light, and these nanoparticle liquids have achieved controlled top-down nanofabrication with predesigned 18 or 16 nm patterns. This proposed strategy is synthetically scalable and structurally extensible and is expected to inspire the design of entirely new forms of nanomaterials.

Analytical chemistry of engineered nanomaterials: Part 2. analysis in complex samples (IUPAC Technical Report)

Abstract Recently, the scope, regulation, legislation, and metrology of the analytical chemistry of engineered nanomaterials (ENMs) have been reviewed in the Part 1 of the IUPAC Technical Report. Chemical analysis of nanomaterials in complex sample matrices presents a substantial challenge for analytical science and regulatory agencies. The purpose of the present Part 2 is to discuss the detection, characterization, and quantification of nanomaterials in samples of complex matrices including methods for sample preparation and fitness for purpose. Analytical methods applied to analysis in matrices of environmental samples, food, cosmetics, and biological samples as well as those used to monitor the fate of ENMs in the environment and biological systems are reported. Tables of numerous recently published works on analyses of typical ENMs with detailed protocols and conclusive comments are presented. There is a rapid development in the field mostly in the stage of accumulation of factual material. The single-particle inductively coupled plasma mass spectrometry is already widely used at the chemical analysis of metal-containing nanoparticles.

Design of Bifunctional Nanocatalysts Based on Zeolites for Biomass Processing.

Bifunctional catalysts consisting of metal-containing nanoparticles (NPs) and zeolite supports have received considerable attention due to their excellent catalytic properties in numerous reactions, including direct (biomass is a substrate) and indirect (platform chemical is a substrate) biomass processing. In this short review, we discuss major approaches to the preparation of NPs in zeolites, concentrating on methods that allow for the best interplay (synergy) between metal and acid sites, which is normally achieved for small NPs well-distributed through zeolite. We focus on the modification of zeolites to provide structural integrity and controlled acidity, which can be accomplished by the incorporation of certain metal ions or elements. The other modification avenue is the adjustment of zeolite morphology, including the creation of numerous defects for the NP entrapment and designed hierarchical porosity for improved mass transfer. In this review, we also provide examples of synergy between metal and acid sites and emphasize that without density functional theory calculations, many assumptions about the interactions between active sites remain unvalidated. Finally, we describe the most interesting examples of direct and indirect biomass (waste) processing for the last five years.

Recent advances in the effective removal of hazardous pollutants from wastewater by using nanomaterials—A review

Environmental nanotechnology has developed rapidly over the past few decades due to the fast advancement of nanotechnology and nanomaterials (NMs). Due to their nanoscale size, NMs are receiving immense attention in research and development worldwide. Their nano size has led to better catalysis, high reactivity, and high adsorption capacity. In wastewater treatment, nanotechnology has significant potential to improve the performance and efficiency of water decontamination; more effectively, it provides a sustainable way to keep water supplies safe. Numerous studies have found that removing harmful components from wastewater by employing nanoparticles in conjunction with various treatment methods is effective. The purpose of the current investigation is to conduct a review of the envisioned applications of various NMs in the treatment of wastewater. These NMs include carbonaceous NMs, metal-containing nanoparticles, and nanocomposites, all of which will be reviewed and highlighted in depth.

Joanna Szpunar, a great chemical researcher internationally recognized, kindly spoke to BrJAC

Joanna Szpunar graduated from the Warsaw University of Technology in 1986 and obtained her Ph.D. (1992) and D.Sc. (Habilitation) (2000) from the University of Warsaw. Since 1997, she works at the National Research Council of France (CNRS). In 2007, she obtained in Poland the title of professor of chemistry. She has broad experience in the field of mass spectrometry-based bio-inorganic speciation analysis and metallomics with a focus on the identification and quantification of trace element species in biological systems and in the chemistry of metal-biomolecule interactions. She is the co-author of a book and approximately 250 scientific publications in peer-reviewed international journals. Joanna Szpunar is a fellow of the Royal Society of Chemistry (UK) and has been, for many years, a member of the boards of Journal of Analytical Atomic Spectrometry' and Metallomics. She regularly gives invited lectures at international analytical chemistry meetings and was the chairperson of the European Winter Conference on Plasma Spectrochemistry (Kraków, Poland) in 2013. The investigations carried out under her supervision and/or with her active participation resulted in the identification of a number of molecular targets of metals in biological systems, as well as contribute to selenometabolomics and selenoproteomics studies in bacteria and plants. In recent years, her interests were broadened to the environmental fate of metal-containing nanoparticles and nanoplastics. She has supervised 12 Ph.D. theses and several post-doctoral fellows. Joanna Szpunar is the laureate of the 2013 Jerzy Fijalkowski Award of the Committee of Analytical Chemistry of the Polish Academy of Sciences and the 2017 European Award for Plasma Spectrochemistry. In recent years, Joanna Szpunar has been involved in collaboration with analytical chemists in Brazil, hosting graduate students from the University of Campinas and the Federal University of Pelotas in the laboratory at the Institute of Analytical Sciences (IPREM) in Pau afiliated with the CNRS, lecturing at the Federal University of Santa Maria and co-supervising a Ph.D. student with work carried out at the University of Pau and the Federal University of Pelotas.

Modular assembly of metal nanoparticles/mesoporous carbon two-dimensional nanosheets

The manipulation of polymeric micelles across extended-length scales is a key challenge in the design of integrated mesoporous materials with well-defined geometry and advanced functions. Herein, we demonstrate a modular assembly strategy to construct metal nanoparticle functionalized mesoporous carbon two-dimensional (2D) nanosheets by organizing zero-dimensional (0D) spherical monomicelle modules on the 2D supporting blocks. The modular assembly process involves two key steps: the “modularization” step is used to synthesize highly uniform metal–catecholamine (MC) complex functionalized monomicelle “modules” that can be conveniently assembled on the 2D supporting blocks (graphene oxide (GO), WS2, and MXene) in the following “assembly” step. After an annealing process, the resultant composites possess a single-layered 2D nanosheet surrounded by two single-layered mesoporous carbon at both sides and exhibit highly ordered mesostructures with large surface areas (~385 m2 g−1), tunable pore sizes (16–25 nm) and highly dispersed metal-containing nanoparticles. Due to the modularity of this assembly process, a range of metal species (Co, Fe, Ni, V, Cu, Pd, FeCo, CoNi, and FeCoNi) can be in-situ incorporated into the 2D mesoporous frameworks, which are partially embedded in the pore walls with the remaining part exposed in the pore channels. Benefiting from the unique textual structures, the resultant GO-derived functional mesoporous carbon nanosheets (Co as the functional species and being annealed at 850 °C) exhibit excellent electrocatalytic activity, long-term stability, and superior methanol tolerance for oxygen reduction reaction, which holds great potential as a catalyst for fuel cells.

Oxidative Potential of Metal-Containing Nanoparticles in Coal Fly Ash Generated from Coal-Fired Power Plants in China

Oxidative Potential of Metal-Containing Nanoparticles in Coal Fly Ash Generated from Coal-Fired Power Plants in China

Combustion conditions and feed coals regulating the Fe- and Ti-containing nanoparticles in various coal fly ash.

Quantitative characteristics and sizes of nanoparticles (NPs) in coal fly ash (CFA) produced in coal-fired power plants as a function of coal type and plant design will help reveal the NP emission likelihood and their environmental implications. However, little is known about how combustion conditions and types of coal regulate the NP abundance in CFAs. In this study, based on single particle (SP)-ICP-MS technology, particle number concentrations (PNCs) and sizes of Fe- and Ti-containing NPs in CFAs were determined for samples collected from power plants of different designs and burning different types of coal. The PNCs of Fe- and Ti-containing NPs in all CFAs measured were in the range of 1.3×107 - 3.4×108 and 6.8×106 - 2.2×108 particles/mg, with the average particle sizes of 111nm and 87nm, respectively. The highest Fe-NP PNCs likely relate to the highest contents of Fe and pyrite in the feed coal. In addition, high TOC in CFAs are associated with metal-containing NPs, resulting in elevated abundances of these NPs with relatively large sizes. Moreover, elevated PNCs of NPs were found in CFAs produced by coal-fired power plants burning low-rank coals and with small installed capacity (especially those under 100-MW units). Compared to cyclone filters, ESPs and FFs with higher removal efficiency typically retain more Fe-/Ti- containing NPs with smaller sizes. Based on a structural equation (SE) model, raw coal properties (coal rank and Fe/Ti content), boiler types, and efficiency of particulate emission control devices likely indirectly affect PNCs of Fe- and Ti-containing NPs by influencing TOC contents and their corresponding metal concentrations of CFAs. This study provides the first analytic and comprehensive information concerning the direct and indirect regulating factors on NPs in various CFAs.

Transbronchial Techniques for Lung Cancer Treatment: Where Are We Now?

The demand for parenchyma-sparing local therapies for lung cancer is rising owing to an increasing incidence of multifocal lung cancers and patients who are unfit for surgery. With the latest evidence of the efficacy of lung cancer screening, more premalignant or early-stage lung cancers are being discovered and the paradigm has shifted from treatment to prevention. Transbronchial therapy is an important armamentarium in the local treatment of lung cancers, with microwave ablation being the most promising based on early to midterm results. Adjuncts to improve transbronchial ablation efficiency and accuracy include mobile C-arm platforms, software to correct for the CT-to-body divergence, metal-containing nanoparticles, and robotic bronchoscopy. Other forms of energy including steam vapor therapy and pulse electric field are under intensive investigation.

Synthesis, Characterization, and Evaluation of Antimicrobial Efficacy of Reduced Graphene-ZnO-Copper Nanocomplex.

The prevalence of antibiotic-resistant diseases drives a constant hunt for new substitutes. Metal-containing inorganic nanoparticles have broad-spectrum antimicrobial potential to kill Gram-negative and Gram-positive bacteria. In this investigation, reduced graphene oxide-coated zinc oxide-copper (rGO@ZnO-Cu) nanocomposite was prepared by anchoring Cu over ZnO nanorods followed by coating with graphene oxide (GO) and subsequent reduction of GO to rGO. The synthesized nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy, elemental analysis, and elemental mapping. Morphologically, ZnO-Cu showed big, irregular rods, rectangular and spherical-shaped ZnO, and anchored clusters of aggregated Cu particles. The Cu aggregates are spread uniformly throughout the network. Most of the ZnO particles were partially covered with Cu aggregates, while some of the ZnO was fully covered with Cu. In the case of rGO@ZnO-Cu, a few layered rGO sheets were observed on the surface as well as deeply embedded inside the network of ZnO-Cu. The rGO@ZnO-Cu complex exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria; however, it was more effective on Staphylococcus aureus than Escherichia coli. Thus, rGO@ZnO-Cu nanocomposites could be an effective alternative against Gram-positive and Gram-negative bacterial pathogens.

"Trojan Horse" Type Internalization Increases the Bioavailability of Mercury Sulfide Nanoparticles and Methylation after Intracellular Dissolution.

Mercury sulfide nanoparticles (HgSNP), as natural metal-containing nanoparticles, are the dominant Hg species in anoxic zones. Although the microbial Hg methylation of HgSNP has been previously reported, the importance of this process in Hg methylation has yet to be clarified due to the lack of knowledge on the internalization and transformation of HgSNP. Here, we investigated the internalization and transformation of HgSNP in microbial methylator Geobacter sulfurreducens PCA through total Hg analysis and different Hg species quantification in medium and cytoplasm. We found that the microbial uptake of HgSNP, via a passive diffusion pathway, was significantly higher than that of the Hg2+-dissolved organic matter (Hg2+-DOM) complex. Internalized HgSNP were dissolved to Hg2+ in cytoplasm with a maximal dissolution of 41%, suggesting a "Trojan horse" mechanism. The intracellular Hg2+ from HgSNP exposure at the initial stage (8 h) was higher than that in Hg2+-DOM group, which led to higher methylation of HgSNP. Furthermore, no differences in methylmercury (MeHg) production from HgSNP were observed between the hgcAB gene knockout (ΔhgcAB) and wild-type strains, suggesting that HgSNP methylation may occur through HgcAB-independent pathways. Considering the possibility of a broad range of hgcAB-lacking microbes serving as methylators for HgSNP and the ubiquity of HgSNP in anoxic environments, this study highlights the importance of HgSNP internalization and methylation in MeHg production and demonstrates the necessity of understanding the assimilation and transformation of nutrient and toxic metal nanoparticles in general.

Nanoparticles in the Era of Antimicrobial Resistance

Antimicrobial resistance is currently a global crisis and is becoming a major issue for human health. The pharmaceutical industries' efforts to create novel therapeutic choices are being slowed down by the active bacterial resistance to traditional antibiotics. Consequently, the rise in infectious diseases caused by resistant bacteria is accompanied by two main issues. Firstly, there is a rise in antibiotic resistance. Secondly, there is a growing disparity between the discovery of new drugs and the rise in antimicrobial resistance. Different treatment strategies are now being in practice to treat bacterial infections, including targeting bacterial virulence factors, bacteriophage therapy, and alteration of the microbiome. Alternative therapeutic approaches are consequently receiving more consideration as traditional antibiotics grow less effective [1].&#x0D; The use of nanoparticles is one of the most promising ways for combating microbial drug resistance. Nitric oxide-releasing nanoparticles (NO NPs), chitosan-containing nanoparticles (chitosan NPs), and metal-containing nanoparticles are a few examples of nanoparticle types that use various ways to simultaneously fight against microorganisms. Nanoparticles can be used to overcome existing drug resistance mechanisms such as decreased drug absorption and increased drug efflux from the microbial cell, biofilm formation, and intrinsic resistance. Finally, antimicrobial drugs can be directed via nanoparticles to the site of infection, enabling greater therapeutic doses to be administered there and overcoming resistance. Antibodies directed against a specific antigen on the surface of the target microorganism can be coupled with nanoparticles. For instance, S. aureus can be killed with great specificity using nanoparticles linked with protein A antibodies [2].&#x0D; Nanoparticles' chemical structure enables longer binding, active targeting of antibiotics with surface functionalization at the target location, and defense against enzymes. As a result, reaching a larger antibiotic concentration in the cell eliminates the need for a higher dose, which reduces adverse effects. Antibiotic nanoparticle conjugates have been recognized by several scientists as a novel class of antibacterial drugs that can lessen the issue of multidrug resistance. Numerous nanoparticles with antimicrobial properties, such as silver, gold, zinc oxide, and titanium oxide, have been tested against microbial pathogens that are multidrug-resistant in conjunction with commercially available antibiotics or peptides [3].&#x0D; Widespread of infectious diseases caused by multiple resistant bacteria is increased day by day and pose a major threat to public health. Therefore, novel antimicrobial strategies are needed to combat the antimicrobial resistance. To reduce adverse effects, nanoparticles may be a preferable option for treating bacterial infections at very low concentrations.&#x0D;