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BF-TEM of HA NPs. A) NANC; B) NAC; C) ANC; D) AC; E) Sigma e Aldrich HA nano-powder. Scale bars are 100 nm. Inserts are the respective SAED patterns.
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Agglomeration dramatically affects many aspects of nanoparticle-cell interactions. Here we show that hydroxyapatite nanoparticles formed large agglomerates in biological medium resulting in extensive particle uptake and dose-dependent cytotoxicity in human macrophages. Particle citration and/or the addition of the dispersant Darvan 7 dramatically r...
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... of HA NPs by precipitation resulted in the formation of fine needle-to plate-like nanoparticles ( Fig. 1A; NANC ¼ non- autoclaved, non-citrated). Autoclaving at 120 C for 20 min resulted in a visible shape change. The NPs were longer, thicker and more lozenge-shaped ( Fig. 1C; ANC ¼ autoclaved, non-citrated). This is consistent with results reported in earlier studies [11,25]. Citration of the non-autoclaved (NAC ¼ non-autoclaved, ...
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... of HA NPs by precipitation resulted in the formation of fine needle-to plate-like nanoparticles ( Fig. 1A; NANC ¼ non- autoclaved, non-citrated). Autoclaving at 120 C for 20 min resulted in a visible shape change. The NPs were longer, thicker and more lozenge-shaped ( Fig. 1C; ANC ¼ autoclaved, non-citrated). This is consistent with results reported in earlier studies [11,25]. Citration of the non-autoclaved (NAC ¼ non-autoclaved, citrated) or auto- claved (AC ¼ autoclaved, citrated) HA NPs did not visibly affect their morphology (Fig. 1B and D, respectively). A synthetic HA nano- powder from SigmaeAldrich ...
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... Citration of the non-autoclaved (NAC ¼ non-autoclaved, citrated) or auto- claved (AC ¼ autoclaved, citrated) HA NPs did not visibly affect their morphology (Fig. 1B and D, respectively). A synthetic HA nano- powder from SigmaeAldrich (cat no. 677418) was used as a com- parison for SAED and was composed of comparatively large, round particles (Fig. 1E). The SAED patterns of the four HA NP preparations and of the SigmaeAldrich HA standard showed that all the mate- rials were polycrystalline with very similar d-spacing and intensity profiles (Fig. 1AeE, ...
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... HA nano- powder from SigmaeAldrich (cat no. 677418) was used as a com- parison for SAED and was composed of comparatively large, round particles (Fig. 1E). The SAED patterns of the four HA NP preparations and of the SigmaeAldrich HA standard showed that all the mate- rials were polycrystalline with very similar d-spacing and intensity profiles (Fig. 1AeE, ...
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... citration, both non-autoclaved and autoclaved HA NPs were slightly shorter in the long axis, whereas the short axis remained unchanged. Phase identification by XRD analysis indi- cated that all four NP preparations were hydroxyapatite and did not contain any other calcium phosphate phases ( Figure SI1 and SI2, Supplementary Information). Surface area and porosity analysis using the BET/BJH methods showed that all four HA NP powders were mesoporous materials (see Figure SI3, Supplementary Infor- mation). ...
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... assessed cell viability after incubating the cells with 125 mg/ ml HA NPs in the absence or presence of 0.125% D7 for 24 h using the MTT assay (Fig. 10). Culturing HMMs with 0.125% D7 alone for 24 h was not significantly toxic. In contrast, both NANC and ANC were significantly toxic when compared to the NA-control and reduced cell viability by about 45%. Dispersion of HA NP agglom- erates by citration, addition of D7 or the combination treatment (citration þ D7) inhibited this toxicity ...
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Citations
... 52−56 The HAp nanoparticle load has demonstrated a high degree of association with cell death. 53,55 In these prior studies, HAp nanoparticles were metabolized in cell lysosomes, which raised intracellular Ca 2+ concentrations and led to lysosomal rupture and cell necrosis. 57 Furthermore, the expected aggregation and subsequent sedimentation of HAp nanoparticles at very high concentrations may induce mechanical damage to the cells, resulting in cytotoxicity. ...
Hydroxyapatite (HAp) has been the main protagonist in the quest for an ideal biomaterial for regenerative medicine over the last half a century. To control its properties, this material has commonly been doped with chemical elements other than its natural stoichiometric constituents: Ca, O, P, and H. Here, we report on the first analysis of the biological response to germanium-doped hydroxyapatite (Ge-HAp). Cytotoxicity, osteo-genic differentiation induction, and colony formation potential were measured on dental pulp stem cells, while the antimicrobial effect was assessed against Gram-negative Escherichia coli, Gram-positive methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans. All analyses were run in comparison to Ge-free HAp. Cell viability was inversely dependent on the nanoparticle concentration and incubation time. Adding Ge to HAp reduced cell viability relative to HAp after 24−72 h incubation periods, but the effect was reversed after longer incubations, when the viability of cells treated with low doses of Ge-HAp exceeded that of HAp-treated cells and became comparable with control culture. Both HAp and Ge-HAp induced mineral formation in the cell culture, but the effect was more pronounced for Ge-HAp. Likewise, relative to both control cells and cells exposed to HAp, Ge-HAp upregulated the expression of all three osteogenic markers analyzed, namely, alkaline phosphatase, RUNX2, and osteocalcin, exerting the key influence on osteogenesis in its early, differentiation stage. The colony formation capacity of stem cells, however, was impaired by HAp and even more so by Ge-HAp. The antimicrobial effect was dependent on the microorganisms tested. Thus, whereas the antimicrobial activity was absent against E. coli, it was evident against MRSA and C. albicans. While the antibacterial activity against MRSA was weakened by the addition of Ge to HAp, the antimycotic activity against C. albicans was intensified with the addition of Ge. These findings demonstrate a significant potential of Ge-doped HAp nanoparticles in regenerative medicine due to their pronounced biocompatibility, osteoinductivity, and antimicrobial activity.
... This difference is due to the fact that SEM reflects the monodispersed particle size in a dried state, whereas DLS reflects the hydrodynamic diameter with hydrated or diffuse layers on the particle periphery [45]. Additionally, larger particles or aggregates in the suspension may shield the signals of smaller particles, leading to an overestimation of measurement values [46][47][48][49]. ...
Chlorantraniliprole is a broad-spectrum insecticide that has been widely used to control pests in rice fields. Limited by its low solubility in both water and organic solvents, the development of highly efficient and environmentally friendly chlorantraniliprole formulations remains challenging. In this study, a low-cost and scalable wet media milling technique was successfully employed to prepare a chlorantraniliprole nanosuspension. The average particle size of the extremely stable nanosuspension was 56 nm. Compared to a commercial suspension concentrate (SC), the nanosuspension exhibited superior dispersibility, as well as superior foliar wetting and retention performances, which further enhanced its bioavailability against Cnaphalocrocis medinalis. The nanosuspension dosage could be reduced by about 40% while maintaining a comparable efficacy to that of the SC. In addition, the chlorantraniliprole nanosuspension showed lower residual properties, a lower toxicity to non-target zebrafish, and a smaller effect on rice quality, which is conducive to improving food safety and the ecological safety of pesticide formulations. In this work, a novel pesticide-reduction strategy is proposed, and theoretical and data-based support is provided for the efficient and safe application of nanopesticides.
... The agglomeration of particles in liquids intensely influences various aspects of nanoparticle-cell interactions. It decreases the contact of particles with the cells due to a reduction in the surface area of them, the level of cellular uptake of particles, and consequently their cytotoxicity [42]. Therefore, the better the dispersion, the higher the anticancer or antibacterial activity [16]. ...
... like structures, they introduce complexity and uncertainty. In addition, the precipitation-based method frequently results in nanoparticle aggregation, which can impact bioreactivity (Motskin et al., 2009;Motskin et al., 2011;Muller et al., 2014;Wang et al., 2019). ...
Micron-scale structure biphasic calcium phosphate (BCP) materials have demonstrated promising clinical outcomes in the field of bone tissue repair. However, research on biphasic calcium phosphate materials at the nanoscale level remains limited. In this study, we synthesize granular-shaped biphasic calcium phosphate nanomaterials with multiple desirable characteristics, including negatively charged surfaces, non-cytotoxicity, and the capability to penetrate cells, using a nanogrinding dispersion process with a polymeric carboxylic acid as the dispersant. Our results reveal that treating human osteoblasts with 0.5 μg/mL biphasic calcium phosphate nanomaterials results in a marked increase in alkaline phosphatase (ALP) activity and the upregulation of osteogenesis-related genes. Furthermore, these biphasic calcium phosphate nanomaterials exhibit immunomodulatory properties. Treatment of THP-1-derived macrophages with BCP nanomaterials decreases the expression of various inflammatory genes. Biphasic calcium phosphate nanomaterials also mitigate the elevated inflammatory gene expression and protein production triggered by lipopolysaccharide (LPS) exposure in THP-1-derived macrophages. Notably, we observe that biphasic calcium phosphate nanomaterials have the capacity to reverse the detrimental effects of LPS-stimulated macrophage-conditioned medium on osteoblastic activity and mineralization. These findings underscore the potential utility of biphasic calcium phosphate nanomaterials in clinical settings for the repair and regeneration of bone tissue. In conclusion, this study highlights the material properties and positive effects of biphasic calcium phosphate nanomaterials on osteogenesis and immune regulation, opening a promising avenue for further research on inflammatory osteolysis in patients undergoing clinical surgery.
... Although the GOAL-0.5 sample showed a low zeta potential after 3 months of storage, the agglomeration was lower than that of GOAL-0. This indicates that the alkali lignin stabilizes the GO nanosheet through electrosteric stabilization mechanisms, which is the combination of electrostatic repulsion and steric hindrance, whereas the addition of 3 mg ml −1 of alkali lignin results in ink with good ink properties, as investigated by UV-vis spectroscopy and zeta potential values [52]. Although the FTIR study indicates that the bonding does not occur after 1 mg ml −1 , adding more alkali molecules might result in steric hindrance in the aqueous dispersion, which leads to higher stability as indicated by digital pictures, zeta potential values and UV-vis spectroscopic analysis. ...
Inkjet-printable ink formulated with graphene oxide (GO) offers several advantages, including aqueous dispersion, low cost, and environmentally friendly production. However, water-based GO ink encounters challenges such as high surface tension, low wetting properties, and reduced ink stability over prolonged storage time. Alkali lignin, a natural surfactant, is promising in improving GO ink's stability, wettability, and printing characteristics. The concentration of surfactant additives is a key factor in fine-tuning GO ink's stability and printing properties. The current study aims to explore the detailed effects of alkali lignin concentration and optimize the overall properties of graphene oxide (GO) ink for drop-on-demand (DOD) thermal inkjet printing. A meander-shaped temperature sensor electrode was printed using the optimized GO ink to demonstrate its practical applicability for commercial purposes. The sensing properties are evaluated using a simple experimental setup across a range of temperatures. The findings demonstrate a significant increase in zeta potential by 25% and maximum absorption by 84.3%, indicating enhanced stability during prolonged storage with an optimized alkali lignin concentration compared to the pure GO dispersions. The temperature sensor exhibits a remarkable thermal coefficient of resistance (TCR) of 1.21 within the temperature range of 25 to 52 ℃, indicative of heightened sensitivity, response, and recovery time. These results highlight the potential of alkali lignin as a natural surfactant for improving the performance and applicability of inkjet-printable GO inks in various technological applications.
... 43 ZP values of NFs less than 5 (5.0 mV) indicate unstable suspensions, which are most likely caused by agglomeration. 44 The average ZP value indicates that the in situ-modified HAPs are extremely stable. The magnitude reveals the colloidal system's potential stability. ...
Fluid−fluid interactions can affect any enhanced oil recovery (EOR)
method, including nanofluid (NF) brine−water flooding. Flooding with NFs changes
wettability and lowers oil−water interfacial tension (IFT). Preparation and
modification affect the nanoparticle (NP) performance. Hydroxyapatite (HAP)
NPs in EOR are yet to be properly verified. HAP was synthesized in this study using
co-precipitation and in situ surface functionalization with sodium dodecyl sulfate in
order to investigate its impact on EOR processes at high temperatures and different
salinities. The following techniques were employed, in that sequence, to verify its
synthesis: transmission electron microscopy, zeta potential, thermogravimetric
analysis, Fourier transform infrared spectroscopy, X-ray diffraction, particle size
analysis, and energy-dispersive X-ray spectra. The outcomes showed the production
of HAP, with the particles being evenly dispersed and stable in aqueous solution. The
particles’ surface charge increased from −5 to −27 mV when the pH was changed
from 1 to 13. The HAP NFs at 0.1 wt % altered the wettability of sandstone core plugs from oil-wet at 111.7 to water-wet at 9.0
contact angles at salinity ranges of 5000 ppm to 30,000 ppm. Additionally, the IFT was reduced to 3 mN/m HAP with an
incremental oil recovery of 17.9% of the initial oil in place. The HAP NF thus demonstrated excellent effectiveness in EOR through
IFT reduction, wettability change, and oil displacement in both low and high salinity conditions.
... Therefore, finding differences between the results of the two techniques seems normal. The DLS results' slightly larger particle size is likely due to unpredictable agglomeration [59,69]. Shalini et al. [70] stated that 187-1039 nm ZnO nanoparticles showed cytotoxic effects in human peripheral blood lymphocytes. ...
The use of iron-nickel alloy nanoparticles (Fe-Ni ANPs) is increasing daily in various fields. People are increasingly exposed to these nanoparticles for occupational and environmental reasons. Our study determined some of the effects of Fe-Ni ANP exposure and impacts on human health at the cellular level. The cytotoxic and genotoxic potentials of Fe-Ni ANPs were investigated by XTT, clonogenic, comet, and GammaH2AX analyses using Beas-2B cells. Annexin V, multicaspase, and cell cycle arrest methods were used to understand the apoptotic mechanism of action. The intracellular ROS method was used to determine the primary mechanism that leads to cytotoxic and genotoxic activity. The Fe-Ni ANPs showed cytotoxic activity with the XTT and clonogenic methods: they had genotoxic potential, as demonstrated via genotoxicity methods. It was determined that the cytotoxic effect was realized by the caspase-dependent apoptotic pathway, and the cells were stopped at the G0/G1 stage by Fe-Ni ANPs. Increased intracellular ROS due to Fe-Ni ANPs led to cytotoxic, genotoxic, and apoptotic activity. Potential risks to human health due to Fe-Ni ANPs were then demonstrated at the cellular level.
... A zeta potential >+30 mV or < − 30 mV is considered a standard value that provides sufficient repulsion forces to prevent particle aggregation. It has been previously documented that particle tendency to aggregate or disperse is affected by surface charge [29]. The repulsion between the naringin-dextrin nanoparticles matched the threshold zeta potential value, which was − 31.6 mV, thus proving the high stability of the prepared formula. ...
Dextrin is a polysaccharide but is small and of low complexity. Naringin is a flavonoid widely known for its pharmacological properties. This study aimed to create a naringin–dextrin nanoformula (NDN) to improve the effects of free naringin against human hepatocellular carcinoma cell lines (HepG2). Transmission electron microscopy, particle size distribution, entrapment efficiency, X-ray diffraction, and Fourier transform infrared spectroscopy were used to characterize NDN. The findings showed that the biological activity of naringin and NDN may be enhanced by inducing reactive oxygen species (ROS) generation and anti-inflammatory reactions mediated by decreased expressions of nuclear factor kappa B and interleukin-8. These changes induced apoptosis via a decrease in the expression levels of B-cell lymphoma-2 and an increase in the expression levels of Bcl-2-associated X protein, caspase-3, caspase-9, p53, and programmed cell death 5. Moreover, the results revealed a decrease in the expressions of isoleucine–glutamine motif-containing GTPase-activating protein 1, isoleucine–glutamine motif-containing GTPase-activating protein 3, and Ras signaling and an increase in the expression of isoleucine–glutamine motif-containing GTPase-activating protein 2. Thus, NDN improved naringin's therapeutic action against HepG2 by activating anti-inflammatory responses and inducing apoptosis via ROS generation, DNA fragmentation, and cell cycle arrest.
... For the bioaccessibility analysis, we developed a three-stage lung-gastricintestinal system assay to mimic the movement of dusts phagocytosed by alveolar macrophages in the human respiratory system, then transported up the oropharynx to subsequently be swallowed and transported into the digestive system. It is generally agreed that most particulate matters deposited in human tracheobronchial airways will be cleared to oropharynx and swallowed into gastrointestinal tract within 24 h (Kruth et al., 1999;Hofmann and Asgharian, 2003;Müller et al., 2014;Kastury et al., 2018;Mutlu et al., 2018). The inhalation-ingestion bioaccessibility assay (IIBA) developed by Kastury et al. (2018) investigated the PTM toxicity in particulate matters migrated from tracheobronchial airways to digestive system, with lung phase PTM bioaccessibility extracted with Gamble's solution. ...
Non-ferrous metal smelting results in heterogenous spatial distribution of potentially toxic metals (PTM) near smelters. In this work, windowsill dusts were collected from smelting (SA) and urban (UJ) sub-areas of Jiyuan (a city affected by >70 years of Pb smelting) to investigate PTM source and bioaccessibility. The <10 μm fraction of dusts were analyzed for total and bioaccessible Pb, Cd, Cu and Zn concentrations; bioaccessibility was analyzed by a three-stage assay (i.e., lung phase, gastric phase and gastrointestinal phase) using artificial lysosomal fluid (ALF, L phase) followed by simulated gastric and gastrointestinal fluids (G and GI phases). This assay mimicked the movement of particles phagocytosed by alveolar macrophages in the respiratory system, then transported up the oropharynx and subsequently swallowed and transported into the digestive system. Zinc had greater bioaccessible concentrations in L and GI phases than other metals, and the mean L phase bioaccessible PTM concentrations in SA were greater than in UJ. The mean L + GI phase bioaccessible concentrations of Pb, Cd, Cu and Zn in SA were 280, 79, 124 and 1458 mg kg⁻¹, while those in UJ were 215, 54, 116 and 598 mg kg⁻¹, respectively. The L phase extracted 87.7 to 98.8 % of PTM within the L + GI assay. Lead had a lower L + GI bioaccessibility than Cd, Cu and Zn (70–76 % vs. 82–92 %). Higher tolerable Cd carcinogenic risks based on bioaccessibility were found in SA sub-area than in UJ while no carcinogenic or non-carcinogenic risk was found for other metals. Lead isotopic ratios indicated that both Pb ore and smelting bottom ash contributed to dust Pb accumulation in SA, while coal burning, lead ore, Pb smelting bottom ash and diesel engine exhaust contributed to dust Pb accumulation in UJ. Overall, results indicated heterogenous distribution of PTM source and bioaccessibility in the vicinity of Pb smelters.
... The variation of the particle morphology might contribute to the surface roughness which may accelerate the faster reaction rate of the process. The agglomerate powder catalyst contributes to a large particle surface; hence, the catalytic activity will be increased [22,23]. In addition, the EDX elemental analysis was conducted to detect the presence of Zn element in Zncyclen. ...
Carbon dioxide (CO2) released from fossil fuel industries into the atmosphere had contributed to the global warming effect and climate change. The development of CO2 separation process through membrane technology had been introduced to capture CO2 from the flue gas. Integration between membrane technology with the biological approach using carbonic anhydrase (CA) enzyme has been explored to enhance carbon capture technology. However, because of the pH and temperature changes, the CA activity had been permanently disturbed. Thus, in this present study, a mimic enzyme (Zn-cyclen) was introduced to resemble the active site of CA enzymes and mimic the bio-catalytic process of CA. Mimic enzyme (Zn-cyclen) was synthesized using the precipitation method of Zinc perchlorate salt solution. The white precipitate of Zn-cyclen was analyzed and characterized for functional group, morphology, and crystallinity behaviour. Then, the developed Zn-cyclen was mixed with the polyvinyl alcohol (PVA) solution and cast onto polyethersulfone (PES) membrane using the dip-coating method to form a complex PES + PVA + Zn-cyclen membrane. The effect of mimic enzyme (Zn-cyclen) loading in the PVA solution were evaluated for swelling and hydrophilic characteristic. The finding shows that Zn-cycle possesses a crystalline structure that is significant in catalytic reaction and the functioning group analysis indicated that the presence of N-H and O-H groups at 1630 cm⁻¹ and 3274 cm⁻¹, respectively, which reflect the protein molecular structure of CA. Integration of Zn-cyclen onto PVA membrane shows that Zn-cyclen has improved the swelling ability of the membrane and increased the hydrophilicity of the complex membrane. Thin film PVA with 3 mg of Zn-cyclen gave the lowest contact angle at 36.4° which possesses the highest hydrophilic. Furthermore, higher swelling ability was observed at Zn-cyclen loading less than 6 mg. The presence of Zn-cycle in the complex PES + PVA membrane was validated with the appearance of the peaks associated with the N – H group at 1629 cm⁻¹. The surface of the complex membrane was rough and the presence of Zn-cyclen cluster or aggregate was observed on the surface of the membrane. The finding indicated addition of Zn-cyclen particle into the PES + PVA membrane formulation has improved the swelling and hydrophilic characteristic of the PES + PVA membrane which is significant in the CO2 hydration application.
