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Caenorhabditis elegans is a useful animal model to assess nanoplastic toxicity. Using polystyrene nanoparticles (PS-NPs) as the example of nanoplastics, we found that exposure to PS-NPs (1–100 μg/L) from L1-larvae for 6.5 days increased expression of cbp-1 encoding an acetyltransferase. The susceptibility to PS-NPs toxicity was observed in cbp-1(RNAi) worms, suggesting that CBP-1-mediated histone acetylation regulation reflects a protective response to PS-NPs. The functions of CBP-1 in intestine, neurons, and germline were required for formation of this protective response. In intestinal cells, CBP-1 controlled PS-NPs toxicity by modulating functions of insulin and p38 MAPK signaling pathways. In neuronal cells, CBP-1 controlled PS-NPs toxicity by affecting functions of DAF-7/TGF-β and JNK MAPK signaling pathways. In germline cells, CBP-1 controlled PS-NPs toxicity by suppressing NHL-2 activity, and NHL-2 further regulated PS-NPs toxicity by modulating insulin communication between germline and intestine. Therefore, our data suggested that the CBP-1-mediated histone acetylation regulation in certain tissues is associated with the induction of protective response to PS-NPs in C. elegans. [Display omitted] • Alteration in CBP-1, an acetyltransferase, mediated protective response to PS-NPs. • CBP-1-mediated signaling cascades in intestine, neuron, and germline were identified. • Germline-intestine communication of insulin was required for protective response. • Our data suggests association of acetylation regulation with protective response to PS-NPs. [ABSTRACT FROM AUTHOR]

With the ongoing commercialization, human exposure to plastic nanoparticles will dramatically increase, and evaluation of their potential toxicity is essential. There is an ongoing discussion on the human health effects induced by plastic particles. For this reason, in our work, we assessed the effect of polystyrene nanoparticles (PS-NPs) of various diameters (29, 44 and 72 nm) on selected parameters of oxidative stress and the viability of human peripheral blood mononuclear cells (PBMCs) in the in vitro system. Cells were incubated with PS-NPs for 24 h in the concentration range of 0.001 to 100 µg/mL and then labeled: formation of reactive oxygen species (ROS) (including hydroxyl radical), protein and lipid oxidation and cell viability. We showed that PS-NPs disturbed the redox balance in PBMCs. They increased ROS levels and induced lipid and protein oxidation, and, finally, the tested nanoparticles induced a decrease in PBMCs viability. The earliest changes in the PBMCs were observed in cells incubated with the smallest PS-NPs, at a concentration of 0.01 μg/mL. A comparison of the action of the studied nanoparticles showed that PS-NPs (29 nm) exhibited a stronger oxidative potential in PBMCs. We concluded that the toxicity and oxidative properties of the PS-NPs examined depended to significant degree on their diameter. [ABSTRACT FROM AUTHOR]

Intestinal barrier plays a crucial function during the response to polystyrene nanoparticles (PS-NPs) in nematode Caenorhabditis elegans. Long non-coding RNAs (lncRNAs) are involved in the control of various biological processes, including stress response. We here used C. elegans to determine intestinal lncRNAs dysregulated by PS-NPs (1–100 μg/L). In intestine of PS-NPs exposed worms, we found four lncRNAs (linc-61 , linc-50 , linc-9 , and linc-2) in response to PS-NPs and with the function in controlling PS-NPs toxicity. The alteration in expressions of these four intestinal lncRNAs reflected a protective response to PS-NPs exposure. During the response to PS-NPs, limited number of transcriptional factors functioned as the downstream targets of these four lncRNAs. linc-2 acted upstream of DAF-16, linc-9 acted upstream of NHR-77, linc-50 functioned upstream of DAF-16, and linc-61 regulated the functions of DAF-16, DVE-1, and FKH-2 to control PS-NPs toxicity. The obtained data demonstrated the important role of lncRNAs in intestinal barrier to mediate a protective response to PS-NPs exposure at low concentrations. • We identified four lncRNAs acting in intestinal cells to control response to PS-NPs. • LncRNAs controlled response to PS-NPs by targeting to limited number of targets. • Certain lncRNAs regulated response to PS-NPs by targeting multiple transcriptional factors. • Some lncRNAs controlled response to PS-NPs by targeting to same transcriptional factor. • The data highlights importance of lncRNAs in intestinal barrier in response to PS-NPs. [ABSTRACT FROM AUTHOR]

Low rank coal (LRC) is difficult to be upgraded by flotation due to the rich oxygen-containing functional groups on its surface. The main objective of this study was to identify the feasibility of surface functionalized polystyrene nanoparticles as LRC flotation collectors. Tetrahydrofurfuryl-functionalized polystyrene nanoparticles (TFPNs) and hydroxyl-functionalized polystyrene nanoparticles (HFPNs) were prepared by emulsion polymerization, and their properties were characterized by X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), Zeta potential and particle size measurement. The effect of nanoparticles properties on the LRC flotation was investigated and the performance between TFPNs, HFPNs, polystyrene nanoparticles (PNs) and diesel oil (DO), was compared. The results show that the LRC flotation recovery of PNs was 2.82%–16.86% higher than that of DO, while that of TFPNs and HFPNs exceeded 28.30%–34.33% and 3.58%–18.92%, respectively, which indicated that the performance of PNs was improved by immobilizing tetrahydrofurfuryl or hydroxyl onto the surface. But surface functionalization degree (SFD) should be kept in an appropriate range, i.e. 5.78%–6.56% for TFPNs, 3.94%–5.62% for HFPNs. TFPNs and HFPNs can specifically deposit onto the LRC with the hydrogen bonding function. By improving the hydrophobicity and roughness with deposited nanoparticles, the flotation performance of LRC was significantly enhanced. The performance of TFPNs was superior to that of HFPNs, which resulted from the strong ability to form hydrogen bond for hydroxyl that reduced nanoparticle hydrophobicity. Effective nanoparticle collectors for LRC flotation were likely to be TFPNs with ∼50 nm diameter, positive Zeta potential and SFD around 6.56%. The balance among colloidal stability, hydrophobicity and selectivity of nanoparticles was an effective way to reduce the dosage of nanoparticle collector and promote its industrial application. The results of this study introduce a new class of special collectors for enhancing LRC flotation and put forward its path to commercial utilization. Image 1 [ABSTRACT FROM AUTHOR]

Polystyrene nanoparticles (PS NPs), originated from breakdown of large plastic wastes, have already caused much concern for their environmental risks on health. This current study was aimed to reveal the toxicological mechanism of PS NPs on developing zebrafish and macrophage cells. To fulfill this purpose, 42 nm PS NPs were exposed to the early development stage of zebrafish for 5 days, the decreased heart rate and locomotor activity of zebrafish larvae were observed. The fluorescent PS NPs were used to precisely assess the accumulation of PS NPs in zebrafish larvae, and the results indicated that PS NPs not only accumulated in digestive system, but also infiltrated into the liver. More importantly, the transcriptomic analysis revealed that a total of 356 genes were differentially expressed and the KEGG class map showed significant differences in the MAPK pathway upon PS NPs treatment. Meanwhile, the induction of oxidative stress and inflammation were also observed in zebrafish larvae. Furthermore, PS NPs also induced oxidative damage and inflammatory response in RAW 264.7 cells, which activated p38 MAPK signal pathway and finally induced cell apoptosis. Our study provides a new understanding of MAPK signaling pathway involved in toxicity mechanism. Image 1 • Nanoplastics posed great potential risks to aquatic organism and mammalian cell. • Nanoplastics induced significant alterations in MAPK pathway in zebrafish larvae. • The induction of oxidative stress and inflammation were correlated with p38 MAPK pathway. • Nanoplastics activated p38 MAPK pathway and finally induced apoptosis. [ABSTRACT FROM AUTHOR]

• The use of a shorter channel improves the separation efficiency of nanoparticles in AF4. • Theoretical aspects have been considered to justify experimental results obtained. • Non-equilibrium diffusion is the most relevant component during separation. • Polystyrene particles have been used as model. • The separation of a mixture of TiO 2 nanoparticles has been carried out. The use of a commercially available short length channel (14 cm length) is proposed to improve the efficiency associated to the separation by asymmetrical flow field-flow fractionation of particles in the nanometer range respect to a standard channel (27 cm length). The effect of channel length on elution times, separation efficiency and resolution have been studied. Polystyrene particles between 50 and 500 nm in size have been used to compare the behavior of both channels. Theoretical aspects based on the different contributions on particle diffusion inside the channel during the separation process have been considered to justify the results obtained. Non-equilibrium diffusion contribution to the efficiency has shown to be the most relevant aspect to be controlled during the separation. The increment of the field strength applied through the cross-flow velocity allows the reduction of diffusion while keep elution times constant. The use of the same cross-flow in a channel with a smaller area is the key factor that justifies the better efficiencies observed along the whole size range studied (improvements that reach factors up to 4.7 in experimental efficiency respect to the standard channel were achieved). The separation of polystyrene particles of 100 and 200 nm was achieved with a resolution of 1.20, whereas a 0.66 value was obtained with the standard channel at the same elution times. Channel recoveries have been also compared under optimized conditions to ensure that no side effects are produced, including the separation of mixtures of TiO 2 nanoparticles. Similar or even better values were obtained with the short length channel, with recoveries higher than 85% for all the polystyrene particles tested and 75% recovery for the TiO 2 nanoparticle mixture, which justifies its use for the separation of nanoparticles, providing better resolutions without compromise elution times or recoveries. [ABSTRACT FROM AUTHOR]

A low-cost method of fabricating large photonic crystal arrays of hexagonal posts without the use of lithography is described, along with an application of enhancing light extraction efficiency in semiconductor light-emitting diodes (LEDs). Polystyrene spheres are deposited onto a wafer surface and then processed to achieve control over photonic crystal lattice properties in a method suitable for fast and repeatable patterning. The spheres serve as an etch mask to extend the photonic crystal formed into the semiconductor surface. This technique is applied to LEDs to increase the top surface light extraction, and 51% wall plug enhancement is demonstrated in deep junction liquid phase epitaxially grown LEDs with absorbing substrates, though is adaptable to any substrate and photonic crystal dimensions. [ABSTRACT FROM PUBLISHER]

• The biological effects of PSNPs depend on the leukocyte cell line used. • Phagocytic cellular function (shown by the THP-1 cell line) likely offer resistance to PSNPs treatment. • PSNPs can cause genotoxicity through different mechanisms of DNA damage. • Assessing toxicity of PSNPs in different cell lines is crucial to elaborate a relevant risk assessment In recent years the terms "micro-/nanoplastics" (MNPLs) have caught special attention due to the increasing levels by which humans are exposed. Among MNPLs, polystyrene nanoparticles (PSNPs) are one of the most represented MNPLs in the environment. These tiny particles may enter into the human body, translocate through human barriers, interacting with blood and lymphatic immune cells, and reaching secondary organs. By using three different human leukocytic cell lines: Raji-B (B-lymphocytes), TK6 (lymphoblasts) and THP-1 (monocytes), we pursued to determine the effects of these PSNPs on the immune cell population. With this aim, the three cell lines were exposed to spherical PSNPs of about 50 nm of diameter and cytotoxicity, cellular uptake, reactive oxygen species (ROS) production, and genotoxicity were assessed at different time-points. Results show differences in all the measured endpoints, among the selected cell lines. Thus, whilst the monocytic THP-1 cells showed the highest particle internalization, no adverse effects were observed in such cells. On the other side, although Raji-B and TK6 showed lesser PSNPs uptake, mild toxicity, ROS production and genotoxicity were detected. These results highlight the importance of the cell line selection when the biological effects of PSNPs are evaluated. [ABSTRACT FROM AUTHOR]

• Antarctic krill juveniles were exposed to two surface charged nanoplastics for 48 h. • Anionic PS-COOH formed large agglomerates with no evident impact on krill fitness. • Nanoscale cationic PS-NH 2 significantly impaired krill behaviour and moulting. • Sinking rate and density of krill faecal pellets were affected by nanoplastics. • Findings suggest potential repercussions on Southern Ocean ecosystems and C export. Plastic debris has been identified as a potential threat to Antarctic marine ecosystems, however, the impact of nanoplastics (<1 μm) is currently unexplored. Antarctic krill (Euphausia superba) is a keystone species of Southern Ocean pelagic ecosystems, which plays a central role in the Antarctic food webs and carbon (C) cycle. Krill has been shown to rapidly fragment microplastic beads through the digestive system, releasing nanoplastics with unknown toxicological effects. Here we exposed krill juveniles to carboxylic (COOH, anionic) and amino- (NH 2 , cationic) polystyrene nanoparticles (PS NPs) and we investigated lethal and sub-lethal endpoints after 48 h. The analysis of PS NP suspensions in Antarctic sea water (SW) media showed that PS-COOH formed large agglomerates (1043 ± 121 nm), while PS-NH 2 kept their nominal size (56.8 ± 3 nm) during the exposure time. After 48 h, no mortality was found but increase in exuviae production (12.6 ± 1.3%) and reduced swimming activity were observed in juveniles exposed to PS-NH 2. The microbial community composition in SW supports the release of krill moults upon PS NP exposure and stimulates further research on the pivotal role of krill in shaping Southern Ocean bacterial assemblages. The presence of fluorescent signal in krill faecal pellets (FPs) confirmed the waterborne ingestion and egestion of PS-COOH at 48 h of exposure. Changes in FP structure and properties were also associated to the incorporation of PS NPs regardless of their surface charge. The effects of PS NPs on krill FP properties were compared to Control 0 h as a reference for full FPs (plastic vs food) and Control 48 h as a reference for more empty-like FPs (plastic vs lack of food). Exposure to PS NPs led to a FP sinking rate comparable to Control 48 h, but significantly lower than Control 0 h (58.40 ± 23.60 m/d and 51.23 ± 28.60 m/d for PS-COOH and PS-NH 2 ; 168.80 ± 74.58 m/d for Control 0 h). Considering the important role played by krill in the food web and C export in the Southern Ocean, the present study provides cues about the potential impact of nanoplastics on Antarctic pelagic ecosystems and their biogeochemical cycles. [ABSTRACT FROM AUTHOR]

Marine diatoms have been identified among the most abundant taxa of microorganisms associated with plastic waste collected at sea. However, the impact of nano-sized plastic fragments (nanoplastics) at single cell and population level is almost unknown. We exposed the marine diatom Skeletonema marinoi to model polystyrene nanoparticles with carboxylic acid groups (PS–COOH NPs, 90 nm) for 15 days (1, 10, 50 μg/mL). Growth, reactive oxygen species (ROS) production, and nano-bio-interactions were investigated. No effect on diatom growth was observed, however Dynamic light scattering (DLS) demonstrated the formation of large PS aggregates which were localized at the diatoms' fultoportula process (FPP), as shown by TEM images. Increase production of ROS and reduction in chain length were also observed upon PS NPs exposure (p < 0.005). The observed PS-diatom interaction could have serious consequences on diatoms ecological role on the biogeochemical cycle of carbon, by impairing the formation of fast-sinking aggregates responsible for atmospheric carbon fixation and sequestration in the ocean sea floor. S. marinoi exposure to PS NPs caused an increase of intracellular and extracellular oxidative stress, the reduction of diatom's chain length and the adhesion of PS NPs onto the algal surface. Image 1 • PN NPs do not affect S. marinoi growth rate. • Fifteen days of exposure to PS NPs affect diatoms at cell and colony level. • PS NPs exposure resulted in a reduction of diatom's colony chain length. • PS NPs aggregates localized at diatom's fultoportula process. • PS NPs causes an increase in intracellular and extracellular ROS. [ABSTRACT FROM AUTHOR]

Civilization development is associated with the use of plastic. When plastic was introduced to the market, it was assumed that it was less toxic than glass. Recently, it is known that plastics are serious ecological problem they, do not degrade and remain in the environment for hundreds of years. Plastic may be degraded into micro-particles < 5000 nm in diameter, and further into nanoparticles (NPs) < 100 nm in diameter. NPs have been detected in air, soil, water and sludge. One of the most commonly used plastics is polystyrene (PS) - a product of polymerization of styrene monomers. It is used for the production of styrofoam and other products like toys, CDs and cup covers. In vivo and in vitro studies have suggested that polystyrene nanoparticles (PS-NPs) may penetrate organisms through several routes i.e. skin, respiratory and digestive tracts. They can be deposited in living organisms and accumulate further along the food chain. NPs are surrounded by "protein corona" that allows them penetrating cellular membranes and interacting with cellular structures. Depending on the cell type, NPs may be transported through pinocytosis, phagocytosis, or be transported passively. Currently there are no studies that would indicate a carcinogenic potential of PS-NPs. On the other hand, the PS monomer (styrene) was classified by the International Agency for Research on Cancer (IARC) as a potentially carcinogenic substance (carcinogenicity class B2). Despite of the widespread use of plastics and the presence of plastic NPs of secondary or primary nature, there are no studies that would assess the effect of those substances on human organism. This study was aimed at the review of the literature data concerning the formation of PS-NPs in the environment, their accumulation along the food chain, and their potential adverse effects on organisms on living various organization levels. Image 1 • The studies suggest that polystyrene nanoparticles may penetrate organisms. • Polystyrene nanoparticles accumulate along the food chain. • Nanoparticles are surrounded by a protein corona that allows penetrating membranes. • In vitro and in vivo studies suggest that polystyrene nanoparticles could be toxic. • Currently there are no studies focused on their effect on human organism. PS-NPs are widely spread in the environment, penetrate living organisms and are toxic. [ABSTRACT FROM AUTHOR]

• The elastic modulus of polystyrene nanoparticles increases linearly by decreasing particle size. • The effect of strain on both elastic modulus and hardness is examined. • Volumetric analysis at the pop-in event indicates shear transformation. • Shear transformation zones inside the polystyrene nanoparticle are discovered. Chemical mechanical planarization (CMP) is an important step in the semiconductor technology. The surface of the wafer after CMP must be defect-free with low roughness. Polymer particles are one of the potential candidates for using as abrasive in CMP. Hence, studying mechanical properties of these abrasives is of great importance. In the current study, the size-dependence elastic modulus and hardness of polystyrene (PS) nanoparticles is investigated via molecular dynamics (MD) simulations. The effect of strain on elastic modulus and hardness is examined and also the impact of strain rate on the mechanical response of PS nanoparticles during compression is studied. Additionally, the pop-in event during loading is precisely examined using volumetric analysis and shear strain distribution inside the nanoparticles is investigated. The results show that the elastic modulus increases linearly by decreasing the particle size while the hardness has a non-linear behavior. The predictions are compared with empirical measurements and good agreement is accomplished. [ABSTRACT FROM AUTHOR]

The presented work investigates particle-induced nanobubble generation in order to extend the applicability of material-selective pressure flotation towards nanoscale materials. During a gas treatment procedure, filtered compressed air in the range of 0 bar–2 bar overpressure was introduced into colloidal suspensions in ultra-purified water until saturation was obtained. Nanobubble formation in the suspension occurred after slow depressurization with a gas vent. Suspensions of platinum nanoparticles and polystyrene beads were used to examine the effects of particle hydrophobicity and roughness. Using nanoparticle-tracking-analysis (NTA), the evaluation of particle size and scattered light intensity showed the occurrence of nanobubbles, both, as a separate phase (bulk nanobubbles) and attached to the particles' surface. The sharply separated nanobubble peak was observed in number density NTA plots of gas treated platinum nanoparticles. The size of the hydrophilic platinum particles remained unchanged. In contrast, for hydrophobic polystyrene particles, the hydrodynamic diameter increased during a gas treatment procedure. The experimental results are understood, on the one hand, as the nucleation of bulk nanobubbles in the cavities of hydrophilic platinum particles and, on the other, as surface-growth of nanobubbles attached to the hydrophobic polymer particles. [ABSTRACT FROM AUTHOR]

Impedance spectroscopy differences between colloidal 295-nm silica and 300-nm polystyrene nanoparticles in deionized water are analyzed in this work. Using two different two-electrode measurement setups, designed for this application, impedance spectroscopy measurements performed directly in the colloidal suspensions with same nanoparticles size, shape and concentration, are fitted using Randles circuit models. The parameter analysis allows to identify the suspension response, the electrode-suspension interfaces response and nanoparticle double layer response. The first measurement system consists of a two aluminum wire electrodes characterized in a frequency range from 0.1Hz to 100 kHz while the second system was two square stainless steel electrodes characterized from 0.1Hz to 5 MHz. According to the results, polystyrene nanoparticles suspension presents higher conductivity and higher values of capacitance than silica suspension. It is revealed that as the nanoparticle concentration decreases, the suspension conductivity decreases for both colloidal suspensions. On the other hand, the electrode polarization effect contributed with high impedance and capacitance values, but showed a contrary behavior with the variation of the nanoparticles concentration. These differences found mainly arise because of the hydrophilic and hydrophobic nature of the silica and polystyrene nanoparticle surfaces. Image 1 • The impedance of 295-nm SiO2 and 300-nm PS nanoparticles in deionized water at the same concentration, are analyzed. • Two different two-electrode systems have been designed to measure the impedance of the silica and polystyrene suspensions. • The impedance spectroscopy of the suspensions is interpreted as a modified equivalent Randles circuit. • PS suspension exhibits higher conductivity than SiO2 suspension due to the hydrophobic nature of the nanoparticle surface. [ABSTRACT FROM AUTHOR]

A series of polystyrene nanoparticles (PS-1, PS-2, PS-3, and PS-4) in aqueous solutions were investigated in terms of morphological structure, size, and size distribution. Synchrotron small-angle X-ray scattering analysis (SAXS) was carried out, providing morphology details, size and size distribution on the particles. PS-1, PS-2, and PS-3 were confirmed to behave two-phase (core and shell) spherical shapes, whereas PS-4 exhibited a single-phase spherical shape. They all revealed very narrow unimodal size distributions. The structural parameter details including radial density profile were determined. In addition, the presence of surfactant molecules and their assemblies were detected for all particle solutions, which could originate from their surfactant-assisted emulsion polymerizations. In addition, dynamic light scattering (DLS) analysis was performed, finding only meaningful hydrodynamic size and intensity-weighted mean size information on the individual PS solutions because of the particles' spherical nature. In contrast, the size distributions were extracted unrealistically too broad, and the volume- and number-weighted mean sizes were too small, therefore inappropriate to describe the particle systems. Furthermore, the DLS analysis could not detect completely the surfactant and their assemblies present in the particle solutions. Overall, the quantitative SAXS analysis confirmed that the individual PS particle systems were successfully prepared with spherical shape in a very narrow unimodal size distribution. [ABSTRACT FROM AUTHOR]

• In situ visualization of polymerization was achieved by fluorescence imaging. • Unique phase separation phenomenon was observed during miniemulsion polymerization. • Superhydrophobic fluorescent nanoparticles were synthesized in rotating packed bed. We report a simply designed liquid sample cell to visualize the processes of emulsion and miniemulsion polymerization by real-time fluorescence imaging of aggregation-induced emission fluorogens (AIEgens) in the emulsions. A unique phase separation phenomenon was observed in the styrene droplets during miniemulsion polymerization, which is beneficial for surface engineering of the polymer nanoparticles. Accordingly, a process intensified synthesis approach to polystyrene (PS) nanodispersion via emulsifier-free miniemulsion polymerization was developed in rotating packed bed reactors. Superhydrophobic fluorescent PS nanoparticles are fabricated via a cost-effective approach and exhibited a water/air contact angle of over 155°, which are promising for fluorescent liquid marbles. These findings not only provide the basis for real-time tracking and characterization of polymerization processes at the microscale via fluorescence imaging of AIEgens, but also offer a new route for the cost-effective production of superhydrophobic polymer nanoparticles for advanced applications. [ABSTRACT FROM AUTHOR]

Nanoplastics are considered contaminants of emerging concern at the global scale. The recent evidence of their occurrence in seawater from the Mediterranean Sea calls for a thorough evaluation of their impact on marine life and in particular on vulnerable life stages such as planktonic embryos. Here, we investigated the impact of increasing nominal concentrations of 50 nm amino-modified (PS-NH 2 ) and 60 nm carboxy-modified (PS-COOH) polystyrene nanoparticles (PS NPs) on the embryonic development of the ascidian Ciona robusta (phylum Chordata), a common benthic invertebrate living in Mediterranean coastal areas with the peculiarity of being an early chordate developmental model. A strong agglomeration of PS-COOH (approx. 1 µm) was observed in natural sea water (NSW) already at time 0, while PS-NH 2 resulted still monodispersed (approx. 130 nm) but largely aggregated after 22 h with a microscale dimension similar to those negatively charged. However, their effect on C. robusta embryos development largely differed at 22 h: PS-COOH did not affect larvae phenotypes nor their development, while PS-NH 2 caused a dose-dependent effect (EC 50 (22 h) of 7.52 μg mL -1 ) with various degrees of phenotype malformations (from mild to severe) and impairment of larval swimming. Embryos (up to 30%) exposed to 15 µg mL -1  PS-NH 2 resulted not developed and the majority was unable to hatch. Calculated PS-NH 2 EC 50 resulted higher than those available for other marine invertebrate species, suggesting a protective role of the egg envelopes surrounding C. robusta embryos toward nanoplastics exposure.

The continued emergence of nanoscale materials for nanoparticle-based therapy, sensing and imaging, as well as their more general adoption in a broad range of industrial applications, has placed increasing demands on the ability to assess their interactions and impacts at a cellular and subcellular level, both in terms of potentially beneficial and detrimental effects. Notably, however, many such materials have been shown to interfere with conventional in vitro cellular assays that record only a single colorimetric end-point, challenging the ability to rapidly screen cytological responses. As an alternative, Raman microspectroscopy can spatially profile the biochemical content of cells, and any changes to it as a result of exogenous agents, such as toxicants or therapeutic agents, in a label free manner. In the confocal mode, analysis can be performed at a subcellular level. The technique has been employed to confirm the cellular uptake and subcellular localization of polystyrene nanoparticles (PSNPs), graphene and molybdenum disulfide micro/nano plates (MoS 2 ), based on their respective characteristic spectroscopic signatures. In the case of PSNPs it was further employed to identify their local subcellular environment in endosomes, lysosomes and endoplasmic reticulum, while for MoS 2 particles, it was employed to monitor subcellular degradation as a function of time. For amine functionalized PSNPs, the potential of Raman microspectroscopy to quantitatively characterize the dose and time dependent toxic responses has been explored, in a number of cell lines. Comparing the responses to those of poly (amidoamine) nanoscale polymeric dendrimers, differentiation of apoptotic and necrotic pathways based on the cellular spectroscopic responses was demonstrated. Drawing in particular from the experience of the authors, this paper details the progress to date in the development of applications of Raman microspectroscopy for in vitro , label free analysis of the uptake, fate and impacts of nanoparticle based materials, in vitro , and the prospects for the development of a routine, label free high content spectroscopic analysis technique., (Copyright © 2020 Byrne, Bonnier, Efeoglu, Moore and McIntyre.)

Polystyrene nanoparticles (PS-NPs) derived from both environmental and occupational sources are an important class of ultrafine particles associated with human pulmonary disorders. The effects of surface charges of particle internalization and toxicity to alveolar cells, especially under conditions comparable to those found during breathing, have not been examined. Here, we applied cyclic stretches (CS) to human alveolar cells during nanoparticle exposure and show an enhanced accumulation of positively charged polystyrene nanoparticles as compared to similar negatively charged particles. The cellular uptake of the positive particles into live cells was visualized with three-dimensional optical diffraction tomography (3-D ODT). The simultaneous application of both periodic stretching as well as positively charged nanoparticles led to blebbing morphology and activation of apoptotic signaling compared to control cells. Our findings provide a better understanding of how surface charge mediates the uptake and toxicity of nanoplastics under the dynamical mechanical conditions relevant for breathing exposures.

Blockage of a nanopore by an analyte molecule has emerged as a promising concept for electrochemical biosensing. Nanoporous structures can be formed on the electrode surface simply by packing spherical nanoparticles in a dense planar arrangement. Modification of the nanoparticles with human serum albumin (HSA) and its interaction with the corresponding antibody (anti-HSA) can induce nanopore-blockage which significantly hinders permeation of the redox probe ([Fe(CN 6 )] 4-/3- ). Interfaces of different parameters were studied using Electrochemical Impedance Spectroscopy (EIS), and counterintuitively, the influence of charge of the nanoparticles and other immobilized entities played a substantial role in the measurement. Our study reveals dominant effects including the presence of mixed output signal and resolves corresponding EIS biosensing-related challenges. Consequently, blocking the nanopores was introduced as an efficient technique which enables the application of EIS-based biosensing to real-world analytical issues.

A great interest surrounds the development of nanoparticles (NPs) for biomedical applications such as drug delivery and cancer therapy. However, the interplay between nanoscale materials and biological systems and the associated hazards have not been completely clarified yet. In this study, bovine oviductal epithelial cells (BOECs) and embryos were used as in vitro models to investigate whether cell mitosis and early mammalian embryo development could be affected by the exposure to polystyrene (PS) nanoparticles. Analysis of the karyotype performed on BOECs exposed to PS-NPs did not show chromosomal anomalies compared to the control, although more tetraploid metaphase plates were observed in the former. In vitro fertilization experiments designed to understand whether exposure to PS-NPs could affect pre-implantation development showed that incubation with PS-NPs decreased 8-cell embryo and blastocyst rate in dose-dependent fashion. The quality of the blastocysts in terms of mean cell percent blastomeres with fragmented DNA was the same in exposed blastocysts compared to controls. These results show that the exposure to PS-NPs may impair development. In turn, this may affect the rate of mitosis in embryos and yield a lower developmental competence to reach the blastocyst stage. This suggests that release in the environment and the subsequent accumulation of PS-NPs into living organisms should be carefully monitored to prevent cytotoxic effects that may compromise their reproduction rates., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Several studies have provided information on environmental nanoplastic particles/debris, but the in vitro cyto-genotoxicity is still insufficiently characterized. The aim of this study is to analyze the effects of polystyrene nanoparticles (PNPs) in the Hs27 cell line. The viability of Hs27 cells was determined following exposure at different time windows and PNP concentrations. The genotoxic effects of the PNPs were evaluated by the cytokinesis-block micronucleus (CBMN) assay after exposure to PNPs. We performed ROS analysis on HS27 cells to detect reactive oxygen species at different times and treatments in the presence of PNPs alone and PNPs added to the Crocus sativus L. extract. The different parameters of the CBMN test showed DNA damage, resulting in the increased formation of micronuclei and nuclear buds. We noted a greater increase in ROS production in the short treatment times, in contrast, PNPs added to Crocus sativus extract showed the ability to reduce ROS production. Finally, the SEM-EDX analysis showed a three-dimensional structure of the PNPs with an elemental composition given by C and O. This work defines PNP toxicity resulting in DNA damage and underlines the emerging problem of polystyrene nanoparticles, which extends transversely from the environment to humans; further studies are needed to clarify the internalization process. [ABSTRACT FROM AUTHOR]