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The Science of the Total Environment May 2024Nanoplastics, arising from the fragmentation of plastics into environmental pollutants and specialized commercial applications, such as cosmetics, have elicited concerns...
Nanoplastics, arising from the fragmentation of plastics into environmental pollutants and specialized commercial applications, such as cosmetics, have elicited concerns due to their potential toxicity. Evidence suggests that the oral ingestion of nanoplastics smaller than 100 nm may penetrate the brain and induce neurotoxicity. However, comprehensive research in this area has been hampered by technical challenges associated with the detection and synthesis of nanoplastics. This study aimed to bridge this research gap by successfully synthesizing fluorescent polystyrene nanoplastics (PSNPs, 30-50 nm) through the incorporation of IR-813 and validating them using various analytical techniques. We administered PSNPs orally (10 and 20 mg/kg/day) to mice and observed that they reached brain tissues and induced cognitive dysfunction, as measured by spatial and fear memory tests, while locomotor and social behaviors remained unaffected. In vitro studies (200 μg/mL) demonstrated a predominant uptake of PSNPs by microglia over astrocytes or neurons, leading to microglial activation, as evidenced by immunostaining of cellular markers and morphological analysis. Transcriptomic analysis indicated that PSNPs altered gene expression in microglia, highlighting neuroinflammatory responses that may contribute to cognitive deficits. To further explore the neurotoxic effects of PSNPs mediated by microglial activation, we measured endogenous neuronal activity using a multi-electrode array in cultured hippocampal neurons. The application of conditioned media from microglia exposed to PSNPs suppressed neuronal activity, which was reversed by inhibitors of microglial activation. Our findings offer detailed insights into the mechanisms by which nanoplastics damage the brain, particularly emphasizing the potential environmental risk factors that contribute to cognitive impairment in neurodegenerative diseases.
Topics: Animals; Mice; Polystyrenes; Microglia; Microplastics; Plastics; Neurons
PubMed: 38490422
DOI: 10.1016/j.scitotenv.2024.171681 -
Human & Experimental Toxicology 2023The current research was performed to evaluate the ameliorative effects of Rhamnetin (RHM) on polystyrene microplastics (PS-MPs)-instigated testicular dysfunction in...
Rhamnetin alleviates polystyrene microplastics-induced testicular damage by restoring biochemical, steroidogenic, hormonal, apoptotic, inflammatory, spermatogenic and histological profile in male albino rats.
The current research was performed to evaluate the ameliorative effects of Rhamnetin (RHM) on polystyrene microplastics (PS-MPs)-instigated testicular dysfunction in male albino rats. 48 albino rats were distributed in four groups, i.e., control, PS-MPs treated, PS-MPs + RHM co-treated and RHM only supplemented group. PS-MPs exposure considerably reduced anti-oxidant enzymes i.e., catalase (CAT), glutathione peroxidase (GSR), superoxide dismutase (SOD) and glutathione reductase (GPx) activities. Whereas, reactive oxygen species (ROS) level along with malondialdehyde (MDA) was considerably escalated in PS-MPs treated rats as well as a potential decline was observed in sperm progressive motility. Additionally, a substantial upsurge was noticed in the count of dead sperms, deformity in the tail, mid-piece and head of sperms in PS-MPs treated rats. PS-MPs exposure also decreased steroidogenic enzymes, 17β-hydroxysteroid dehydrogenase (17β-HSD), steroidogenic acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) expressions. Moreover, the levels of inflammatory indices i.e., Interleukin-6 (IL-6), Nuclear factor kappa-B (NF-κB), Interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) activity were also increased in PS-MPs administrated group. Besides it increased the expression of apoptotic markers (Bax and caspase-3) expression. Whereas, anti-apoptotic marker i.e., Bcl-2 expression was reduced. Moreover, luteinizing hormone (LH), follicle-stimulating hormone (FSH) as well as plasma testosterone levels were also decreased. PS-MPs exposure also led to a substantial histopathological damage in testicular tissues. However, RHM supplementation potentially reduced the damaging effects of PS-MPs in the reproductive tissues of male albino rats. Thus, the current study revealed, RHM possesses potential to prevent PS-MPs-induced testicular damage due to its anti-oxidant anti-apoptotic, anti-inflammatory as well as androgenic properties.
Topics: Male; Rats; Animals; Antioxidants; Microplastics; Plastics; Polystyrenes; Semen; Testis; Oxidative Stress; Testosterone
PubMed: 37122069
DOI: 10.1177/09603271231173378 -
ACS Macro Letters Jan 2021The glassy polymer of polystyrene (PS) enjoys a good reputation as a promising optical material; however, the inherent brittleness hinders its further applications....
The glassy polymer of polystyrene (PS) enjoys a good reputation as a promising optical material; however, the inherent brittleness hinders its further applications. Conventional toughening methods are realized based on the premise of a sacrifice in transparency and stiffness. In this work, we found an unprecedented strategy to address these obstacles by combining extensional stress-induced ductility and suppressing physical aging. PS-based film with a high stiffness, long-term ductility, and excellent transparency is achieved by introducing a styrene-butadiene block copolymer into the PS matrix and subsequently annealing stretched. A nanofibrillar structure of the polybutadiene (PB) phase is formulated surrounded by a PS matrix, and thus, the elongation at break enhances from 3.1% up to 86.8%, accompanying the yield strength enhanced from 25.5 to 62.2 MPa. More significantly, compared with neat PS, these films survive from physical aging and persistent ductility over time. The morphology deformation induced by stress makes an obvious contribution to the improvement of transparency. Investigating the dynamics of chain segments indicates that the incorporation of the copolymer can restrict rearrangement and local relaxation to the PS chain. This work could pave a potential route toward high-performance PS and might be transferable to other glassy polymers with a fragile character.
Topics: Butadienes; Polymers; Polystyrenes; Rejuvenation; Tensile Strength
PubMed: 35548990
DOI: 10.1021/acsmacrolett.0c00733 -
Colloids and Surfaces. B, Biointerfaces Jan 2016The adsorption of polyclonal immunoglobulin G (IgG) on negatively charged polystyrene microparticle suspension (latex) was studied by using the Laser Doppler Velocimetry...
The adsorption of polyclonal immunoglobulin G (IgG) on negatively charged polystyrene microparticle suspension (latex) was studied by using the Laser Doppler Velocimetry (LDV) measurements. Using this technique, the dependence of the electrophoretic mobility of particles on the IgG concentration in the suspension was measured for various ionic strengths and pH 3.5. The increase in the electrophoretic mobility was quantitatively interpreted in terms of the 3D electrokinetic model. On the other hand, the maximum coverage of IgG on latex was determined using the depletion method based on AFM imaging. It was shown that IgG adsorption was irreversible and that its maximum coverage on the microspheres increased from 1.4mgm(-2) for 0.001M NaCl to 2.0mgm(-2) for 0.15M NaCl. This was interpreted in terms of reduced electrostatic repulsion among adsorbed molecules. The stability of IgG monolayers on the particles was confirmed in separate experiments where changes in its electrophoretic mobility were monitored over prolonged time periods. Additionally, the acid-base properties of the IgG monolayers on latex were determined in pH cycling experiments. The isoelectric point of the IgG monolayers on the microspheres was 4.8. The results obtained in this work indicate that basic physicochemical characteristics of IgG can be acquired via electrophoretic mobility measurements using microgram quantities of the protein.
Topics: Adsorption; Immunoglobulin G; Microspheres; Polystyrenes
PubMed: 26296563
DOI: 10.1016/j.colsurfb.2015.07.037 -
Journal of Visualized Experiments : JoVE Jul 2015We present a template-free method for "polymerizing" nanoparticles into long chains without side branches. A variety of nanoparticles are encapsulated in...
We present a template-free method for "polymerizing" nanoparticles into long chains without side branches. A variety of nanoparticles are encapsulated in polystyrene-block-poly(acrylic acid) (PSPAA) shells and then used as monomers for their self-assembly. Spherical PSPAA micelles upon acid treatment are known to assemble into cylindrical micelles. Exploiting this tendency, the core-shell nanoparticles are induced to aggregate, coalesce, and then transform into long chains. When more than one type of nanoparticles are used, random and block "copolymers" of nanoparticles can be obtained. Detailed procedures are reported for the PSPAA encapsulation of nanoparticles, homo- and co-polymerization of the core-shell nanoparticles, separation and purification of the resulting nanoparticle chains. Transformations of single-line chains into double- and triple-line chains are also presented. The synergy between the polymer shell and the embedded nanoparticles leads to an unusual chain-growth polymerization mode, giving long nanoparticle chains that are distinct from the products of the traditional step-growth aggregation process.
Topics: Acrylates; Metal Nanoparticles; Micelles; Microscopy, Electron, Transmission; Polymerization; Polystyrenes
PubMed: 26274566
DOI: 10.3791/52954 -
Journal of the American Chemical Society Apr 2002A new type of giant amphiphilic molecule has been synthesized by covalently connecting a lipase enzyme headgroup to a maleimide-functionalized polystyrene tail (40...
A new type of giant amphiphilic molecule has been synthesized by covalently connecting a lipase enzyme headgroup to a maleimide-functionalized polystyrene tail (40 repeat units). The resulting biohybrid forms catalytic micellar rods in water.
Topics: Fungal Proteins; Hydrogen-Ion Concentration; Lipase; Models, Molecular; Polystyrenes; Surface-Active Agents
PubMed: 11960447
DOI: 10.1021/ja017809b -
International Journal of Molecular... Dec 2023Microplastics (MPs) are emerging pollutants and pose a significant threat to marine ecosystems. Although previous studies have documented the mechanisms and toxic...
Microplastics (MPs) are emerging pollutants and pose a significant threat to marine ecosystems. Although previous studies have documented the mechanisms and toxic effects of aging MPs in various environments, the impact of the marine environment on MPs remains unclear. In the present study, the aging process of polystyrene (PS) in seawater was simulated and the changes in its physicochemical properties were investigated. Our results showed that the surface of the PS eroded in the seawater, which was accompanied by the release of aged MPs with a smaller size. In situ optical photothermal infrared microspectroscopy revealed that the mechanism of PS aging was related to the opening of the carbonyl group and breaking of the bond between carbon and benzene removal. To verify the toxic effects of aged PS, was exposed to PS. Aged PS resulted in a greater reduction in locomotion, vitality, and reproduction than virgin PS. Mechanistically, aged PS led to oxidative stress, high glutathione s-transferase activity, and high total glutathione in worms. Together, our findings provided novel information regarding the accelerated aging of PS in seawater and the increased toxicity of aged PS, which could improve our understanding of MPs' ecotoxicity in the marine environment.
Topics: Animals; Polystyrenes; Plastics; Caenorhabditis elegans; Ecosystem; Water Pollutants, Chemical; Microplastics; Aging; Seawater
PubMed: 38139049
DOI: 10.3390/ijms242417219 -
Analytical Chemistry Jan 2020Mass cytometry (MC) measures metal isotope signals from single cells and bead samples. Since large numbers of isotopes can be employed as labels, mass cytometry is a...
Mass cytometry (MC) measures metal isotope signals from single cells and bead samples. Since large numbers of isotopes can be employed as labels, mass cytometry is a powerful analytical technique for multiparameter cytometric assays. The calibration protocol in MC is a critical algorithm, which employs metal-encoded microbeads as an internal standard to correct the data for instrumental signal drift. The current generation of commercially available beads carries four lanthanide elements (cerium, europium, holmium, and lutetium). However, this is not sufficient to calibrate the full span of detection channels, ranging from yttrium (89 amu) to bismuth (209 amu), which are now available. To address this issue we prepared polystyrene microbeads encoded with seven elements (yttrium, indium, and bismuth in addition to the four lanthanides) by multistage dispersion polymerization for MC calibration and normalization. The bead synthesis conditions were optimized to obtain microbeads that were uniform in size and generated strong MC signal intensities at similar levels for the eight encoded isotopes. Metal ion leaching from the beads under storage and application conditions was also examined. We demonstrated that the precision of normalized MC signals in the MC detection channels was improved by employing seven-element-encoded microbeads as a standard.
Topics: Calibration; Cell Separation; Limit of Detection; Mass Spectrometry; Metals, Heavy; Microspheres; Particle Size; Polystyrenes; T-Lymphocytes
PubMed: 31815445
DOI: 10.1021/acs.analchem.9b03935 -
Journal of Chromatography. A Jun 2019Ground silica monolith particles of quite smaller average size (2 μm) have been prepared by sol-gel process followed by soft grinding and calcination. Next a highly...
Ground silica monolith particles of quite smaller average size (2 μm) have been prepared by sol-gel process followed by soft grinding and calcination. Next a highly efficient chromatographic stationary phase has been prepared by reaction of those particles with (3-chloropropyl) trimethoxysilane followed by initiator attachment and modification of polystyrene by reversible addition-fragmentation chain transfer polymerization. The resultant phase of ca 3 μm particle size was packed in micro-columns (1.0 mm × 300 mm & 1.0 mm × 150 mm) to show the separation efficiencies as high as 67,600 and 35,500 plates/ column, respectively, for the separation of 5 small test molecules at a mobile phase flow rate of 25 μL/min. The 300 mm column shows a separation efficiency better than any of the commercially available conventional packed columns so far. Multiple shapes and high surface roughness as well as reduced particle size of the stationary phase of this study seem to contribute to such enhanced separation efficiency.
Topics: Chemistry Techniques, Analytical; Chromatography, High Pressure Liquid; Particle Size; Polystyrenes; Silicon Dioxide
PubMed: 30765127
DOI: 10.1016/j.chroma.2019.02.013 -
Analytical Biochemistry Apr 2021The enzyme-linked immunosorbent assay (ELISA) is a widely used diagnostic technique. In ELISA, detection of the target biomolecules is achieved through selective capture...
The enzyme-linked immunosorbent assay (ELISA) is a widely used diagnostic technique. In ELISA, detection of the target biomolecules is achieved through selective capture by appropriate antibody immobilized on a solid support. Our study addresses the application of surface plasmon resonance to an assessment of the polystyrene modification efficiency for promoting adsorption of biomolecules. A method facilitating the development of advanced immobilization strategies for biofunctionalization of polystyrene surface was evolved. The proposed approach uses formation of a thin layer of polystyrene over the SPR chip surface, thus enabling a detailed characterization of biomolecular interactions at the polystyrene surface.
Topics: Enzyme-Linked Immunosorbent Assay; Polystyrenes; Surface Plasmon Resonance; Surface Properties
PubMed: 33450285
DOI: 10.1016/j.ab.2021.114101