A toxicological profile of silica nanoparticles

Competition between cotton and velvetleaf and their tolerance to pyrithiobac-sodium as affected by silicon nutrition

Although silicon nutrition in crops has been reported to improve growth and herbicide tolerance, the response of crop-associated weeds has not been studied. To support or reject the hypothesis that silicon nutrition can affect the tolerance of velvetleaf to pyrithiobac-sodium, affecting crop-weed competition, this study was conducted as a dose-response study in which cotton and velvetleaf grown in soil with or without K2SiO3 + silicate-solubilizing bacteria (SSB) were sprayed with pyrithiobac-sodium. Some enzymes involved in lignin biosynthesis, antioxidant, and herbicide metabolism were measured to find physiological changes. The findings accept the hypothesis above for the first time. Silicon nutrition could disrupt pyrithiobac-sodium selectivity for controlling velvetleaf in cotton. Regardless of treatments, velvetleaf accumulated more silicon and lignin than cotton. Unlike phenylalanine ammonia-lyase, the activity of cytochrome P450 reductase (1.3 vs. 0.7 U/g), glutathione S-transferase (1.7 vs. 1.2 U/g), superoxide dismutase (21.7 vs. 12.5 U/mg), and catalase (443.9 vs. 342.5 U/mg) was higher in cotton than in velvetleaf, grown in soil without silicon nutrition. All enzymes became more active with silicon nutrition, but the increase was higher in velvetleaf. In field studies, velvetleaf benefited from silicon nutrition more than cotton, enhancing the competitive ability of velvetleaf in cotton and reducing further crop yield. K2SiO3 + SSB caused a 29.7 % increase in velvetleaf biomass, which caused the greatest damage to cotton seed (80.9 %) and lint (69.2 %) yields. It is recommended to avoid soil nutrition with K2SiO3 + SSB in velvetleaf-infested cotton fields, where velvetleaf control with pyrithiobac-sodium is intended.

Advances in silica nanoparticles for agricultural applications and biosynthesis

Nanotechnology has emerged as a revolutionary force in modern agriculture, opening new avenues for crop enhancement and sustainable farming practices. This review systematically evaluates the roles of silica nanoparticles (SiO2 NPs) in agricultural applications, with particular emphasis on their biosynthesis pathways and functional mechanisms. SiO2 NPs have demonstrated considerable potential to enhance crop resilience against both biotic (pathogens, pests) and abiotic (heavy metals, salinity, drought) stresses through phytohormonal regulation, defense gene activation, and metabolic modulation. As nanocarriers, these particles enhance pesticide and fertilizer delivery accuracy, reduce environmental contamination, and promote plant growth. Biosynthesis methods of SiO2 NPs range from conventional physical-chemical techniques to eco-friendly green approaches, including the utilization of biological cells/extracts, natural biomaterials, and peptide templates. Although green synthesis offers sustainability advantages, the agricultural adoption of SiO2 NPs faces critical challenges, such as insufficient understanding of their long-term environmental persistence and ecotoxicological impacts, high production costs related to green synthesis, and incomplete regulatory frameworks. Addressing these challenges is essential to enable their broader use in agriculture.

Silicon nutrition enhances CYP450s- and GST-mediated metabolism of sulfosulfuron in wheat and an invasive weed, Hordeum vulgare subsp. spontaneum

BACKGROUND

Although silicon nutrition in crops has been reported to improve growth and herbicide tolerance, the response of crop-associated weeds has not been studied.

RESULTS

In glasshouse studies, co-applying potassium silicate (K2SiO3) + silicate-solubilizing bacteria (SSB) synergistically increased wheat and spontaneous barley's silicon content by 2.2- and 2.6-fold, respectively. Based on the median effective dose, it increased wheat (2.2-2.8-fold) and spontaneous barley (3.5-3.7-fold) tolerance to sulfosulfuron. With/without silicon nutrition, pretreating plant species with malathion or 4-chloro-7-nitrobenzofurazan made them more sensitive to sulfosulfuron. Without silicon nutrition, cytochrome P450 reductase (1.3 versus 0.7 U g-1), glutathione S-transferase (1.7 versus 1.2 U g-1), superoxide dismutase (23.7 versus 14.5 U mg-1), and catalase (412.9 versus 311.5 U mg-1) were more active in wheat than in spontaneous barley. All enzymes became more active with silicon nutrition, the increase was higher in spontaneous barley. Field studies conducted at two locations showed that without silicon nutrition and sulfosulfuron, spontaneous barley reduced wheat grain yield by 36.8-41.5%. Without sulfosulfuron, co-applying K2SiO3 + SSB synergistically increased spontaneous barley biomass by 37.4-76.1%, reducing wheat grain yield by 59.0-62.1%. Without silicon nutrition, sulfosulfuron (40 g ha-1) controlled spontaneous barley by 71.8-98.5%. Furthermore, it controlled spontaneous barley by 18.7-29.9% when K2SiO3 + SSB was co-applied.

CONCLUSION

Silicon nutrition made both plants more tolerant to sulfosulfuron due to the increased activity of enzymes that metabolize herbicides and scavenge reactive oxygen species. It should be avoided in spontaneous barley-infested wheat fields because it is more beneficial for spontaneous barley and reduces sulfosulfuron efficacy. © 2025 Society of Chemical Industry.

Metabolomics reveals that phosphatidylethanolamine can alleviate the toxicity of silica nanoparticles in human lung A549 cells

Silica nanoparticles (SiNPs) are widely utilized in occupational settings where they can cause lung damage through inhalation. The objective of this research was to explore the metabolic markers of SiNPs-induced toxicity on A549 cells by metabolomics and provide a foundation for studying nanoparticle-induced lung toxicity. Metabolomics analysis was employed to analyze the metabolites of SiNPs-treated A549 cells. LASSO regression was applied for selection, and protective measure experiments were conducted to validate the efficacy of selected potential toxicity mitigators. After SiNPs treatment, 23 differential metabolites were identified, including lipids, nucleotides, and organic oxidants. Pathway analysis revealed involvement in various biological processes. LASSO regression further identified six metabolites significantly associated with SiNPs toxicity. Notably, phosphatidylethanolamine (PE (14:1(9Z)/14:0)) showed enrichment in six significant metabolic pathways and with an AUC of 1 in the ROC curve. Protective measure experiments verified its protective effect on A549 cells and demonstrated its considerable inhibition of SiNPs-induced cytotoxicity. This study elucidated SiNPs-induced cytotoxicity on A549 cells and identified PE as a potential toxicity mitigator. These findings contribute to understanding the mechanisms of nanoparticle-induced lung toxicity and inform occupational health preventive strategies.

Revolutionizing Nanovaccines: A New Era of Immunization

Infectious diseases continue to pose a significant global health threat. To combat these challenges, innovative vaccine technologies are urgently needed. Nanoparticles (NPs) have unique properties and have emerged as a promising platform for developing next-generation vaccines. Nanoparticles are revolutionizing the field of vaccine development, offering a new era of immunization. They allow the creation of more effective, stable, and easily deliverable vaccines. Various types of NPs, including lipid, polymeric, metal, and virus-like particles, can be employed to encapsulate and deliver vaccine components, such as mRNA or protein antigens. These NPs protect antigens from degradation, target them to specific immune cells, and enhance antigen presentation, leading to robust and durable immune responses. Additionally, NPs can simultaneously deliver multiple vaccine components, including antigens, and adjuvants, in a single formulation, simplifying vaccine production and administration. Nanovaccines offer a promising approach to combat food- and water-borne bacterial diseases, surpassing traditional formulations. Further research is needed to address the global burden of these infections. This review highlights the potential of NPs to revolutionize vaccine platforms. We explore their mechanisms of action, current applications, and emerging trends. The review discusses the limitations of nanovaccines, innovative solutions and the potential role of artificial intelligence in developing more effective and accessible nanovaccines to combat infectious diseases.

Advancing analytical and graphical methods for binary and ternary mixtures: The toxic interactions of divalent metal ions in human lung cells

Humans are exposed to various environmental chemicals, particles, and pathogens that can cause adverse health outcomes. These exposures are rarely homogenous but rather complex mixtures in which the components may interact, such as through synergism or antagonism. Toxicologists have conducted preliminary investigations into binary mixtures of two components, but little work has been done to understand mixtures of three or more components. We investigated mixtures of divalent metal ions, quantifying the toxic interactions in a human lung model. Eight metals were chosen: heavy metals cadmium, copper, lead, and tin, as well as transition metals iron, manganese, nickel, and zinc. Human alveolar epithelial cells (A549) were exposed to individual metals and sixteen binary and six ternary combinations. The dose-response was modeled using logistic regression in R to extract LC50 values. Among the individual metals, the highest and lowest toxicity were observed with copper at an LC50 of 102 μM and lead at an LC50 of 5639 μM, respectively. First and second-order interaction coefficients were obtained using machine learning-based linear regression in Python. The resulting second-degree polynomial model formed either a hyperbolic or elliptical conic section, and the positive quadrant was used to produce isobolograms and contour plots. The strongest synergism and antagonism were observed in cadmium-copper and iron-zinc, respectively. A three-way interaction term was added to produce full ternary isobologram surfaces, which, to our knowledge, are a significant first in the toxicology literature.

Mesoporous silica nanoparticles co-loaded with lysozyme and vancomycin for synergistic antimicrobial action

Nanotechnology offers a novel strategy for enhancing the susceptibility of pathogens resistant to traditional antibiotics. Another effective strategy is combination therapy, where multiple agents are used together to improve treatment efficacy. In this study, both nanoparticle-based formulation and combinatorial therapy were utilized to develop a potent antibacterial system targeting infectious bacteria. Lysozyme (Lys) and Vancomycin (Van) were co-loaded onto mesoporous silica nanoparticles (MSNs), forming Lys-Van-MSNs. The antimicrobial activity of these nanoparticles was evaluated by determining the minimum inhibitory concentration (MIC) against Staphylococcus aureus. The MIC values for Lys-Van-MSNs were 0.85 µg/ml for Van and 0.168 mg/ml for Lys, reflecting reductions of 86.4% and 93.7%, respectively, compared to the free forms. Additionally, cytotoxicity was tested using MTT, ROS, and hemolysis assays on human cell lines (breast, fibroblast, and AGS), showing over 80% cell viability, indicating minimal toxicity. The MSN-based formulation, with its synergistic antibacterial effects, reduced drug dosage, and high biocompatibility, offers a practical and effective solution for addressing bacterial infections.

Comparative Assessment of Cellular Responses to Microscale Silica Morphologies in Human Gastrointestinal Cells: Insights for Occupational Health

Silicon dioxide (SiO2), commonly known as silica, is a naturally occurring mineral extracted from the Earth's crust. It is widely used in commercial products such as food, medicine, and dental ceramics. There are few studies on the health effects of pyrogenic and colloidal silica after ingestion. No research has compared the impact of microscale morphologies on mitochondrial activity in colon cells after acute exposure. The results show that crystalline and amorphous silica had a concentration-independent effect on cells, with an initial increase in mitochondrial activity followed by a decrease. Vitreous silica did not affect cells. Diatomaceous earth and pyrogenic silica had a concentration-dependent response, causing a reduction in mitochondrial activity as concentration increased. Diatomaceous earth triggered the highest cellular response, with mitochondrial activity ranging from 78.84% ± 12.34 at the highest concentration (1000 ppm) to 62.54% ± 17.43 at the lowest concentration (0.01 ppm) and an average H2O2 concentration of 1.48 ± 0.15 RLUs. This research advances our understanding of silica's impact on human gastrointestinal cells, highlighting the need for ongoing exploration. These findings can improve risk mitigation strategies in silica-exposed environments.

Benchmark dose determining airborne crystalline silica particles based on A549 lung-cell line survival in an in vitro study

Crystalline silica has emerged as a prominent occupational toxicant over extended periods, leading to the development of lung disease and cancer. The objective of this investigation is to establish a benchmark dose (BMD) for crystalline silica micro and nanoparticles based on the dehydrogenase activity of the A549 lung-cell line. The impact of exposure to crystalline silica micro-particles (C-SiO2 MPs) and crystalline silica nanoparticles (C-SiO2 NPs) on A549 epithelial lung cells was examined for durations of 24 and 72 h to evaluate cell viability using the MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay. The determination of dose-response and BMD was carried out through the BMD software v 3.2. The findings reveal a dose-dependent relationship between cell viability and both C-SiO2 MPs and -NPs. The BMDL values for 24 h treatment of C-SiO2 MPs and -NPs were determined to be 2.26 and 0.97 µg/ml, respectively, based on exponential models. Correspondingly, these values were found to be 1.17 and 0.85 µg/ml for the 72 h treatment. This investigation underscores the significance of particle size as a contributing factor in assessing occupational health risks. Moreover, the utilization of BMDL can facilitate the determination of more precise values for occupational exposures by considering various parameters associated with particle presence.

Enhancing Maize Yield and Quality with Metal-Based Nanoparticles without Translocation Risks: A Brief Field Study

Our previous studies have shown physiological and yield intensification of selected crops with the application of nanoparticles (NPs). However, the impact on the quantitative, qualitative, and yield parameters of maize (Zea mays L.) in field conditions remains highly debated. This study aimed to evaluate the effects of zinc oxide (ZnO-NPs), gold NPs anchored to meso-biosilica (Au-NP-bioSi), and titanium dioxide (TiO2-NPs) as biological stimulants under field conditions during the vegetation season of 2021 in the Central European region. The study assessed the effects on the number of plants, yield, yield components, and nutritional quality, including mineral nutrients, starch, and crude protein levels. The potential translocation of these chemically-physically stable NPs, which could pose a hazard, was also investigated. The results indicate that Au-NP-bioSi and ZnO-NPs-treatments were the most beneficial for yield and yield components at a statistically significant level. Mineral nutrient outcomes were varied, with the NP-free variant performing the best for phosphorus-levels, while Au-NP-bioSi and ZnO-NPs were optimal for crude protein. Starch content was comparable across the TiO2-NPs, Au-NP-bioSi, and control variants. Importantly, we observed no hazardous translocation of NPs or negative impacts on maize grain quality. This supports the hypothesis that NPs can serve as an effective tool for precise and sustainable agriculture.

Ordered Mesoporous Silica Delivering siRNA as Cancer Nanotherapeutics: A Comprehensive Review

Nanosized mesoporous silica has emerged as a promising flexible platform delivering siRNA for cancer treatment. This ordered mesoporous nanosized silica provides attractive features of well-defined and tunable porosity, structure, high payload, and multiple functionalizations for targeted delivery and increasing biocompatibility over other polymeric nanocarriers. Moreover, it also overcomes the lacunae associated with traditional administration of drugs. Chemically modified porous silica matrix efficiently entraps siRNA molecules and prevents their enzymatic degradation and premature release. This Review discusses the synthesis of silica using the sol-gel approach and the advantages with different silica mesostructure. Herein, the factors affecting the synthesis of silica at nanometer scale, shape, porosity and nanoparticle surface modification are also highlighted to attain the desired nanostructured silica carriers. Additional emphasis is given to chemically modified silica delivering siRNA, where the silica nanoparticle surface was modified with different chemical moieties such as amine modified with (3-aminoropyl) triethoxysilane, polyethylenimine, chitosan, poly(ethylene glycol), and cyclodextrin polymer modification to attain high therapeutic loading, improved dispersibility and biocompatibility. Upon systemic administration, ordered mesoporous nanosized silica encounters blood cells, immune cells, and organs mainly of the reticuloendothelial system (RES). Thereby, biocompatibility and biodistribution of silica based nanocarriers are deliberated to design principles for smart and efficacious nanostructured silica-siRNA carriers and their clinical trial status. This Review further reports the future scopes and challenges for developing silica nanomaterial as a promising siRNA delivery vehicle demanding FDA approval.

A review on toxicity mechanism and risk factors of nanoparticles in respiratory tract

This comprehensive review focuses on various dimensions of nanoparticle toxicity, emphasizing toxicological characteristics, assessment techniques, and examinations of relevant studies on the effects on biological systems. The primary objective is to comprehend the potential risks associated with nanoparticles and to provide efficient strategies for mitigating them by consolidating current research discoveries. For in-depth insights, the discussions extend to crucial aspects such as toxicity associated with different nanoparticles, human exposure, and nanoparticle deposition in the human respiratory tract. The analysis utilizes the multiple-path particle dosimetry (MPPD) modeling for computational simulation. The SiO2 nanoparticles with a volume concentration of 1% and a particle size of 50 nm are used to depict the MPPD modeling of the Left upper (LU), left lower (LL), right upper (RU), right middle (RM), and right lower (RL) lobes in the respiratory tract. The analysis revealed a substantial 67.5% decrease in the deposition fraction as the particle size increased from 10 nm to 100 nm. Graphical representation emphasizes the significant impact of exposure path selection on nanoparticle deposition, with distinct deposition values observed for nasal, oral, oronasal-mouth breather, oronasal - normal augmenter, and endotracheal paths (0.00291 μg, 0.00332 μg, 0.00297 μg, 0.00291 μg, and 0.00383 μg, respectively). Consistent with the focus of the review, the article also addresses crucial mitigation strategies for managing nanoparticle toxicity.

High inflammatory cytokines gene expression can be detected in workers with prolonged exposure to silver and silica nanoparticles in industries

Occupational health must be strictly considered in industries particularly in nanoparticle factories where workers were exposed to different types of chemicals. We measured the serum levels of inflammatory cytokines in workers who developed skin lesions after exposure to silver and silica nanoparticles. Using a questionnaire in this cross-sectional study, we identified 110 workers in nanoparticle industries who were exposed to silver and silica nanoparticles. We also included 40 healthy subjects as controls from the administrative department of the same factories who were not exposed to nanoparticles. Peripheral blood samples used to measure the mRNA levels of inflammatory cytokines by qRT-PCR. In comparison with the control group, the workers who developed skin lesions had significantly higher levels of interleukin IL4, IL6, IL8, and TNF-α, particularly after two or three decades of exposure to silver and silica nanoparticles. Participants who were exposed to silver had higher levels of IL6 and IL8 compared with those who were exposed to silica. Necessary measures must be considered to protect workers in nanoparticle industries against the potential toxic effects of these compounds. Our network pharmacology study suggests corresponding biochemical pathways for these disorders.

Quantitative determination of the intracellular uptake of silica nanoparticles using asymmetric flow field flow fractionation coupled with ICP mass spectrometry and their cytotoxicity in HepG2 cells

We established a size separation method for silica nanoparticles (SiNPs) measuring 10, 30, 50, 70, and 100 nm in diameter using asymmetric flow field flow fractionation hyphenated with inductively coupled plasma mass spectrometry (AF4-ICP-MS), and evaluated the cytotoxicity of SiNPs in human hepatoma HepG2 cells. Analysis of the mixture sample revealed that nanoparticles of different sizes were eluted at approximately 2-min intervals, with no effect on each elution time or percentage recovery. Compared with larger SiNPs, smaller SiNPs exhibited high cytotoxicity when the volume of SiNPs exposed to the cells was the same. We measured SiNPs in culture medium and inside cells by AF4-ICP-MS and found that approximately 17% of SiNPs in the mixture of five differently sized particles were absorbed by the cells. Transmission electron microscopy revealed that 10 nm SiNPs formed aggregates and accumulated in the cells. Based on AF4-ICP-MS analysis, there is no clear difference in the particle volume absorbed by the cells among different sizes. Therefore, the high toxicity of small SiNPs can be explained by the fact that their large surface area relative to particle volume efficiently induces toxicological influences. Indeed, the large surface area of 10 nm SiNPs significantly contributed to the production of reactive oxygen species.

Advances in the study of silica nanoparticles in lung diseases

Silicon dioxide nanoparticles (SiNPs) are one of the major forms of silicon dioxide and are composed of the most-abundant compounds on earth. Based on their excellent properties, SiNPs are widely used in food production, synthetic processes, medical diagnostics, drug delivery, and other fields. The mass production and wide application of SiNPs increases the risk of human exposure to SiNPs. In the workplace and environment, SiNPs mainly enter the human body through the respiratory tract and reach the lungs; therefore, the lungs are the most important and most toxicologically affected target organ of SiNPs. An increasing number of studies have shown that SiNP exposure can cause severe lung toxicity. However, studies on the toxicity of SiNPs in ex vivo and in vivo settings are still in the exploratory phase. The molecular mechanisms underlying the lung toxicity of SiNPs are varied and not yet fully understood. As a result, this review summarizes the possible mechanisms of SiNP-induced lung toxicity, such as oxidative stress, endoplasmic reticulum stress, mitochondrial damage, and cell death. Moreover, this study provides a summary of the progression of diseases caused by SiNPs, thereby establishing a theoretical basis for future studies on the mechanisms of SiNP-induced lung toxicity.

Recent Developments of Nano Flame Retardants for Unsaturated Polyester Resin

For many years, efforts have been made to reduce the flammability of unsaturated polyester resins (UPRs), which are often used in the rail, shipbuilding, and construction industries. Without modification, they often fail to meet fire safety standards. Despite a rich history of flame retardants (FRs) applied to UPRs, researchers seek new solutions that will provide lower flammability and smoke density, as well as attaining a lower environmental impact from the composites. The objective of the study is to highlight the most important recent research on promising nano FRs in order to promote their further development. Mechanisms of action of several groups of nano FRs, such as clay-based, carbon-based, transition metal compounds, layered double hydroxides, polyhedral oligomeric silsesquioxanes, and others, including bio-based, have been studied. Particular emphasis has been laid on nano FRs applied to UPRs, and their influences on thermal stability, flammability, and mechanical properties. Moreover, the environmental impact and toxicity of nano FRs have been discussed. Results have proved that nano FRs applied at low loadings may significantly improve thermal stability, with a simultaneous increase or only a slight decrease in mechanical properties. However, attention on related environmental issues has highlighted the necessity of carefully selecting novel nano FRs.

Nanosilica size-dependent toxicity in Ceriodaphnia reticulata (Cladocera)

Silica nanoparticles (SiNP) are the most produced nanomaterials due to their variety of applications. When released to environments, surface water bodies are their main final sink. SiNP toxicity is still inconclusive and may vary according to particle properties such as their size. We analyzed the size-related effects of SiNP (22 and 244 nm) on mortality, life history traits, and oxidative stress in the cladoceran Ceriodaphnia reticulata. The smaller SiNP (LC5072 h: 105.5 µg/ml) were more lethal than the larger ones (LC5072 h >500 µg/ml). The 22 nm-sized SiNP decreased the number of molts and neonates, increased superoxide dismutase and inhibited glutathione S-transferase activities, while larger SiNP did not exert substantial effects on the organisms at the tested concentrations. In conclusion, SiNP toxicity depended on their size, and this information should be considered for regulatory purposes and to the development of safe-by-design nanoproducts to ultimately guarantee the environment protection.

Additive Manufacturing of Bioactive Glass and Its Polymer Composites as Bone Tissue Engineering Scaffolds: A Review

Bioactive glass (BG) and its polymer composites have demonstrated great potential as scaffolds for bone defect healing. Nonetheless, processing these materials into complex geometry to achieve either anatomy-fitting designs or the desired degradation behavior remains challenging. Additive manufacturing (AM) enables the fabrication of BG and BG/polymer objects with well-defined shapes and intricate porous structures. This work reviewed the recent advancements made in the AM of BG and BG/polymer composite scaffolds intended for bone tissue engineering. A literature search was performed using the Scopus database to include publications relevant to this topic. The properties of BG based on different inorganic glass formers, as well as BG/polymer composites, are first introduced. Melt extrusion, direct ink writing, powder bed fusion, and vat photopolymerization are AM technologies that are compatible with BG or BG/polymer processing and were reviewed in terms of their recent advances. The value of AM in the fabrication of BG or BG/polymer composites lies in its ability to produce scaffolds with patient-specific designs and the on-demand spatial distribution of biomaterials, both contributing to effective bone defect healing, as demonstrated by in vivo studies. Based on the relationships among structure, physiochemical properties, and biological function, AM-fabricated BG or BG/polymer composite scaffolds are valuable for achieving safer and more efficient bone defect healing in the future.

Label-Free Identification of Carbonaceous Particles Using Nonlinear Optical Microscopy

The adverse health effects of ambient carbonaceous particles (CPs) such as carbon black (CB), black carbon (BC), and brown carbon (BrC) are becoming more evident and depend on their composition and emission source. Therefore, identifying and quantifying these particles in biological samples are important to better understand their toxicity. Here, we report the development of a nonlinear optical approach for the identification of CPs such as CB and BrC using imaging conditions compatible with biomedical samples. The unique visible light fingerprint of CB and BrC nanoparticles (NPs) upon illumination with a femtosecond (fs) pulsed laser at 1300 nm excitation wavelength is an effective approach for their identification in their biological context. The emission from spectral features of these CPs was investigated with time-domain fluorescence lifetime imaging (FLIM) to further support their identification. This study is performed for different types of CPs embedded in agarose gel as well as in in vitro mammalian cells. The unique nonlinear emissive behavior of CP NPs used for their label-free identification is further complementary with fluorophores typically used for specific staining of biological samples thus providing the relevant bio-context.

A review of the extraction methods and advanced applications of lignin-silica hybrids derived from natural sources

The global trend of increasing energy demand along the large volume of wastewater generated annually from the paper pulping and cellulose production industries are considered as serious dilemma that may need to be solved within these current decades. Within this discipline, lignin, silica or lignin-silica hybrids attained from biomass material have been considered as prospective candidates for the synthesis of advanced materials. In this study, the roles and linking mechanism between lignin and silica in plants were studied and evaluated. The effects of the extraction method on the quality of the obtained material were summarized to show that depending on the biomass feedstocks, different retrieval processes should be considered. The combination of alkaline treatment and acidic pH adjustment is proposed as an effective method to recover lignin-silica with high applicability for various types of raw materials. From considerations of the advanced applications of lignin and silica materials in environmental remediation, electronic devices and rubber fillers future valorizations hold potential in conductive materials and electrochemistry. Along with further studies, this research could not only contribute to the development of zero-waste manufacturing processes but also propose a solution for the fully exploiting of by-products from agricultural production.

Silica nanoparticle remodeling under mild conditions: versatile one step conversion of mesoporous to hollow nanoparticles with simultaneous payload loading

A binary mixture of mesoporous silica nanoparticles plus organic polyammonium additive (dye or drug) is cleanly converted upon mild heating into hollow nanoparticles. The remodeled nanoparticle shell is an organized nanoscale assembly of globular additive/silica subunits and cancer cell assays show that a loaded drug additive is bioavailable.

Amorphous silica nanoparticles caused lung injury through the induction of epithelial apoptosis via ROS/Ca2+/DRP1-mediated mitochondrial fission signaling

The adverse effects of amorphous silica nanoparticles (SiNPs) exposure on the respiratory system were increasingly recognized, however, its potential pathogenesis still remains not fully elucidated. So, this study aimed to explore its effects on pulmonary injury, and to investigate related mechanisms. Histological investigations illustrated SiNPs triggered the lung injury, mainly manifested as alveolar structure destruction, collagen deposition, and mitochondrial ultrastructural injury. In particular, SiNPs greatly enhanced pulmonary ROS and TUNEL positive rate in lungs, both of which were positively correlated with lung impairments. Further, the underlying mechanisms were investigated in cultured human bronchial epithelial cells (16HBE). Consistent with the in vivo findings, SiNPs caused the impairments on mitochondrial structure, as well as the activation of ROS generation and oxidative injury. Upon SiNPs stimuli, mitochondrial respiration was greatly inhibited, while Ca2+ overload in cytosol and mitochondria owing to ER calcium release was noticed, resulting in mitochondrial-dependent epithelial apoptosis. More importantly, mitochondrial dynamics was imbalanced toward a fission type, as evidenced by upregulated DRP1 and its phosphorylation at Ser616 (DRP1s616), while downregulated DRP1s637, and also MFN1, MFN2. Mechanistic investigations revealed that the activation of ROS/Ca2+ signaling promoted DRP1-mediated mitochondrial fission by SiNPs, forming a vicious cycle, and ultimately contributing to apoptosis in 16HBE. In summary, our results disclosed SiNPs caused pulmonary injury through the induction of epithelial apoptosis via a ROS/Ca2+/DRP1-mediated mitochondrial fission axis.