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In this study, we aimed to synthesize magnetically well-dispersed nanosensors for detecting dissolved oxygen (DO) in water, and explore their biological applications. Firstly, we synthesized two kinds of magnetic nanoparticle with average sizes of approximately 82 nm by one-step emulsion polymerization: polystyrene magnetic nanoparticles (Fe 3 O 4 @Os1-PS) and polymethylmethacrylate magnetic nanoparticles (Fe 3 O 4 @Os1-PMMA). Both types of nanoparticle present good dispersibility and fluorescence stability. The nanoparticles could be used as oxygen sensors that exhibited a high DO-sensitivity response in the range 0-39.30 mg/L, with a strong linear relationship. The nanoparticles have good magnetic properties, and so they could be recycled by magnet for further use. Recovered Fe 3 O 4 @Os1-PS still presented high stability after continued use in oxygen sensing for one month. Furthermore, Fe 3 O 4 @Os1-PS was employed for detecting the bacterial oxygen consumption of Escherichia coli (E-coli) to monitor the metabolism of bacteria. The results show that Fe 3 O 4 @Os1-PS provide high biocompatibility and non-toxicity. Polystyrene magnetic nanoparticles therefore present significant potential for application in biological oxygen sensing., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Stimuli-responsive drug delivery systems are highly desirable for improved therapeutic efficacy and minimized adverse effects of drugs. Mesoporous silica nanoparticles (MSNs) functionalized with pentadentate ligands, N-(3-trimethoxysilylpropyl)ethylenediamine triacetate (TSP-DATA), in the presence of metal ions with and without myoglobin (Mb)-containing surface-accessible histidine residues, were constructed for pH-triggered controlled release. The DATA ligands immobilized on the MSN pore outlets could encapsulate cargo within the pores by metal latching across pore openings, and release efficiency increased with the increase of surface density of the DATA ligands. The release efficiencies for the metal-chelating protein nanogates, through multiple-site binding of Mb with the metal-chelating ligands, were higher than those for the metal-latching ligand nanogates but were almost independent of surface density of the ligands investigated. Both the metal-latching ligands and the metal-chelating proteins played a synergetic role in gating MSNs for high-loading drug delivery and stimuli-responsive controlled release. The constructed Mb-Cu(2+)-gated MSN delivery system has promising applications in targeted drug therapy of tumors.

Peritoneal implantation of cancer cells, particularly postoperative seeding metastasis, frequently occurs in patients with primary tumors in the stomach, colon, liver, and ovary. Peritoneal carcinomatosis is associated with poor prognosis. In this work, we evaluated the prophylactic effect of intraperitoneal administration of selenium (Se), an essential trace element and a putative chemopreventive agent, on peritoneal implantation of cancer cells. Elemental Se nanoparticles were injected into the abdominal cavity of mice, into which highly malignant H22 hepatocarcinoma cells had previously been inoculated. Se concentrations in the cancer cells and tissues, as well as the efficacy of proliferation inhibition and safety, were evaluated. Se was mainly concentrated in cancer cells compared to Se retention in normal tissues, showing at least an order of magnitude difference between the drug target cells (the H22 cells) and the well-recognized toxicity target of Se (the liver). Such a favorable selective distribution resulted in strong proliferation suppression without perceived host toxicity. The mechanism of action of the Se nanoparticle-triggered cytotoxicity was associated with Se-mediated production of reactive oxygen species, which impaired the glutathione and thioredoxin systems. Our results suggest that intraperitoneal administration of Se is a safe and effective means of preventing growth of cancer cells in the peritoneal cavity for the above-mentioned high-risk populations., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The current results show that epigallocatechin-3-gallate (EGCG), in the form of phenolic anions at pH 8.0, can effectively disperse selenium nanoparticles. However, at gastric juice pH (1.0), the EGCG-dispersed selenium nanoparticles (referred to as E-Se) extensively aggregated, so that nano features largely disappeared. This demonstrates that deprotonated phenolic anions of EGCG play an important role in maintaining E-Se stability and suggests that E-Se would suffer from reduced oral bioavailability. To validate this conjecture, size-equivalent E-Se and bovine serum albumin (BSA)-dispersed selenium nanoparticles (B-Se), whose physicochemical properties were not altered at pH 1.0, were orally administered to selenium-deficient mice. In comparison to B-Se, the bioavailabilities of E-Se as indicated with hepatic and renal glutathione peroxidase activity and hepatic selenium levels were significantly (p < 0.01) reduced by 39, 32, and 31%, respectively. Therefore, the present study reveals that size-equivalent selenium nanoparticles prepared by different dispersers do not necessarily guarantee equivalent oral bioavailability.

Fluorine-doped tin dioxide (FTO) nanocrystals were prepared with a sol-gel process followed by a hydrothermal treatment using SnCl(4) and NH(4)F as SnO(2) and fluorine dopant, respectively. The nanostructure and composition were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), zeta potential analysis, electrochemical measurement technology and X-ray photoelectron spectroscopy (XPS) respectively. The diameter of the fluorine doped SnO(2) nanocrystal in rutile-type structure is about 10nm. Compared to the pure SnO(2) nanocrystals, the fluorine doped SnO(2) nanocrystals can be dispersed homogeneously in H(2)O, forming transparent sol with high stability. The powder of fluorine doped SnO(2) nanocrystals could be obtained by removing the solvent, and the electrical resistivity properties were measured by a four-point probe measurement. The results show that sheet resistances (Rs) of fluorine doped SnO(2) decrease with the increasing NH(4)F/Sn molar ratio in the range from 0 to 2. However, further increase of NH(4)F/Sn molar ratio from 2 to 5 leads to higher sheet resistance. The F/Sn molar ratio of fluorine doped SnO(2) measured by XPS is about 0.18 when NH(4)F/Sn molar ratio is equal to 2, and the sheet resistance of fluorine doped SnO(2) powder is 110Ω/□., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The application of unstable nutraceuticals in food formulation will be encouraged by designing delivery vehicles through the assembly of biopolymers at a variety of scales, from nanoscopic to macroscopic. Due to their high nutritional value and natural occurrence, egg white proteins (EWPs) have garnered interests recently for use as building blocks. In this review, the physicochemical properties of EWPs and the main techniques to promote their assembly were discussed at first. Following that, a thorough summary of current research was provided on the biopolymer- and emulsion-type carriers, which were created by assembling EWPs with or without the presence of exogenous proteins, polysaccharides, polyphenols, or functional groups. Furthermore, these carriers' stabilizing effects on curcumin, polyunsaturated fatty acids, vitamins, catechins, anthocyanins, carotenoids and resveratrol were categorized and emphasized. Lastly, we put forth the concerns and further perspectives of the EWPs-based delivery systems. A deeper comprehension of the relationship between structure and function clarifies the rational designation of EWPs-based carriers with desired properties. [Display omitted] • EWPs are suitable building blocks for edible biopolymer- and lipid-type vehicles. • EWPs are triggered to assemble with themselves or other compounds to create vehicles. • These carriers improved the stability, bioactivity and bioavailability of the loaded agent. • Mucopenetration, gut fermentation and allergenicity are top safety concerns. • EWP-based 3D/4D printing, fat substitutes and intelligent systems require more research. [ABSTRACT FROM AUTHOR]

A SnO 2 –NbC–C ternary composite was constructed using hydrothermal and ball milling methods. For this special design, the SnO 2 –NbC nanoparticles were uniformly coated with ultra-thin carbon nanosheets. It should be noted that the NbC nanoparticles can accommodate the volume variation of SnO 2 particles and prevent Sn agglomeration, resulting in good electrical contact between particles and low charge transfer resistance. After 100 cycles of 0.2 Ag-1, the SnO 2 –NbC–C nanocomposite exhibited a high capacity of 956.0 mAhg-1, and a rate capacity of 955.2 mAhg-1, and after 500 cycles of 5.0 Ag-1, it achieved a capacity of 704.1 mAhg-1. In addition, the SnO 2 –NbC–C composite remained stable after 200 and 700 cycles without agglomeration. [ABSTRACT FROM AUTHOR]

In this work, gliadin nanoparticles were fabricated by liquid antisolvent precipitation (LAS) method using a synergistic combination of thermally denatured ovalbumin (OVA) with cosurfactant gemini dodecyl O -glucoside (Gemini-C12) as stabilizers. The interaction between OVA and Gemini-C12 was characterized by surface tension, fluorescence spectroscopy, isothermal titration calorimetry, and circular dichroism analysis, respectively. The relationship between the properties of gliadin nanoparticles and Gemini-C12 concentration was interpreted on the basis of OVA-Gemini-C12 interaction. When the concentration below critical micelle concentration (CMC), Gemini-C12 could decrease the interfacial tension and enhance the adsorption strength of OVA on particle surface, thereby increasing the nucleation rate and giving gliadin nanoparticles with smaller size. Besides, the monomeric cosurfactant could plug the vacancies left by OVA at solid-liquid interface and therefore prohibit the aggregation and agglomeration of gliadin nanoparticles during storage and freeze-drying. Above CMC, free micelles were formed in the bulk and the surfactant molecules tended to reside in micelles rather than be adsorbed at the solid-liquid interface, which compromised the protective effect of cosurfactant and resulted in gliadin nanoparticles with larger size and lower storage stability and redispersibility. [ABSTRACT FROM AUTHOR]

Ti 3 C 2 /TiO 2 /rGO nanosheets were synthesized as anode materials for potassium ion batteries (KIBs) using modified Hummers, freeze drying, and thermal reduction in this paper. Layered Ti 3 C 2 /TiO 2 /rGO nanosheets were synthesized by in-situ formation of rGO and TiO 2 nanoparticles between Ti 3 C 2 layers. As one of the most important members of MXenes family, Ti 3 C 2 exhibits unique electronic characteristics, high specific surface area, strong electrical conductivity and chemically active surface, which can enhance electrode capacity. There are three ways to increase electrode conductivity and capacity: Firstly, rGO is applied as the substrate for the inlaying of TiO 2 and Ti 3 C 2 nanoparticles and nanosheets. Secondly, rGO may also buffer electrode volume changes during charging and discharging processes. In addition, the enormous surface area of rGO makes Ti 3 C 2 and TiO 2 nanoparticles dispersion well, and Ti 3 C 2 and TiO 2 nanoparticles can well separate rGO nanoparticles and prevent them from stacking up again. The synergistic effect of the three can efficiently relieve the stress and provide a rapid transport pathway between electrons and ions. The flake structure of Ti 3 C 2 /TiO 2 /rGO is advantageous to the stability of SEI film, which makes the material maintain good activity during charge and discharge process, and significantly increases its electrochemical performance. Therefore, Ti 3 C 2 /TiO 2 /rGO electrode has a high reversible capacity of 349.2 mAhg−1 after 200 cycles of 100 mAg−1 current, and a high stable capacity of 229.3 mAhg−1 after 500 cycles of 500 mAg−1 current, and has exceptional rate performance. The structure of Ti 3 C 2 /TiO 2 /rGO composite remains stable after 500 cycles, and no agglomeration occurs. The detailed reaction mechanism of Ti 3 C 2 /TiO 2 /rGO electrode as KIBs anode was analyzed by SEM, XRD, Raman, TGA, FT-IR, BET, TEM, XPS, EDS, CV, EX-situ XRD, ex-situ TEM, and so on. Therefore, it can be concluded that the Ti 3 C 2 /TiO 2 /rGO composite is an appropriate anode material for KIBs. [Display omitted] • Ti 3 C 2 /TiO 2 /rGO nanosheets were synthesized using modified Hummers, freeze drying, and thermal reduction. • The flake structure of Ti 3 C 2 /TiO 2 /rGO is advantageous to the stability of SEI film, which makes the material maintain good activity. • RGO acts as a substrate for TiO 2 and Ti 3 C 2 nanoparticles to buffer the volume change of the electrode during the charging and discharging process. • The synergistic effect of Ti 3 C 2 , TiO 2 , and rGO can efficiently relieve the stress and provide a rapid transport pathway between electrons and ions. • Ti 3 C 2 /TiO 2 /rGO electrode has a high reversible capacity of 349.2 mAhg−1 after 200 cycles of 100 mAg−1 , and 229.3 mAhg−1 after 500 cycles of 500 mAg−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • IPD is used to modify ZIF-8 nanoparticles by a simple coordination interaction. • IPD@ZIF-8 nanoparticles exhibit excellent dispersity in various solvents. • H 2 /CH 4 selectivity of PI/IPD@ZIF-8 MMM with 45 wt% loading is increased by 46.6%. • The CO 2 plasticization resistance of PI/IPD@ZIF-8 MMMs is improved from 21 to 30 bar. Metal organic frameworks (MOFs) are ideal fillers for preparing mixed matrix membranes (MMMs) because of their molecular sieving property. However, MOF nanoparticles are not easy to be dispersed, which limits their application in MMMs with high MOFs loading. In this study, highly dispersed ZIF-8 nanoparticles with diameter of around 50 nm were prepared by coating isophthalic dihydrazide (IPD) molecular layer onto their surfaces via coordination interaction (abbre. IPD@ZIF-8). Benefiting from the highly stable and highly dispersed IPD@ZIF-8 solution, MMMs with high nanoparticles loading content and excellent uniformity are achieved. The modification of IPD on the surface of ZIF-8 nanoparticles greatly enhances the interfacial affinity between ZIF-8 as filler and 6FDA-Durene polyimide (PI) as polymer matrix under the interaction of strong hydrogen bond between them. Gas permeation results reveal that the H 2 permeability of IPD@ZIF-8 mixed PI (PI/IPD@ZIF-8) MMM with 45 wt% loading content is up to 8000 Barrer and the corresponding ideal selectivities of H 2 /CH 4 and H 2 /N 2 gas pairs are 15.1 and 13.0, which increase by 46.6% and 32.7%, respectively, comparing to those of ZIF-8 mixed PI (PI/ZIF-8) MMMs. The comprehensive separation performance of PI/IPD@ZIF-8 MMMs surpasses the 2008 Robeson's upper bounds. The surface modification of IPD enhances the CO 2 plasticization resistance property of PI/IPD@ZIF-8 MMMs from 21 bar to 30 bar. This study provides a facile and easy-operated strategy for the surface modification of MOF nanoparticles, and opens up a new way for the preparation of MMMs with high filler loading and good quality. [ABSTRACT FROM AUTHOR]

Material Nano-genesis has gradually obtained more technical feedback and support in the study of lithium batteries, but problems such as volume expansion still need in-depth study. In this paper, SnO 2 –TiO 2 –CNS ternary composites were prepared by hydrothermal method and ball milling. Depending on the layered structure, the SnO 2 –TiO 2 nanoparticles are uniformly attached to carbon nanosheets. It is noteworthy that the volume variation of SnO 2 was alleviated by mixed TiO 2 and CNS, thus generating a wider space to move around for the lithium ion during the conduction process. The STC was tested for 100 cycles at 0.2 Ag-1 and the capacity was achieved 1046.1 mAhg−1. At 1.0 Ag-1, the capacity of STC can attain 1443.3 mAhg−1 after 1000 cycles. Then, the SEM image of the recovered electrode material was measured, and it was observed that the SnO 2 –TiO 2 –CNS composite remained stable. [ABSTRACT FROM AUTHOR]

Novel water-soluble CaF 2 :Tb 3+ nanoparticles were synthesized using benzoimidazole-5-carboxylic acid (Ligand) as surfactant. The particle size of the nanoparticles is below 10 nm. The investigation of fluorescence properties showed that there exists energy transfer from the surface coating of nanoparticles to Tb 3+ leading to the sensitized fluorescence emission of Tb 3+ . The luminescence lifetimes of Tb 3+ were 937.56 μs (37.41%) and 2.78 ms (62.59%). It is more important that Cu 2+ and Fe 3+ can give rise to emission quenching to the Tb 3+ of nanoparticles, especially Cu 2+ . In the region of 2.5×10 −5 –5×10 −4 M, the higher the concentration of Cu 2+ or Fe 3+ is, the stronger fluorescence quenching to the Tb 3+ is. Additionally, the possible mechanisms of the luminescence quenching were also discussed. [ABSTRACT FROM AUTHOR]

Glaucoma is a major cause of irreversible blindness in the world and filtering surgery is commonly carried out to control intraocular pressure. Failure of filtering surgery is usually due to postoperative scarring, and fibroblast proliferation, collagen production and subconjunctival fibrosis play a prominent role in obstructing aqueous humor from the anterior chamber to the subconjunctival space. Zinc oxide (ZnO) nanoparticles have been widely applied in biomedical fields. However, the influence of ZnO nanoparticles on human tenon fibroblasts (HTFs) is still unclear. In the present study, we first explored the effects of various concentrations of ZnO nanoparticles on HTFs proliferation, reactive oxygen species (ROS) generation, cell cycle arrest, and apoptosis. Further, we determined the changes of transforming growth factor-β (TGF-β1), fibronectin (FN) extra domain A (ED-A), and procollagen I carboxyterminal propeptide (PICP) at mRNA and protein levels, explored the effect of ZnO nanoparticles on the collagen lattice contraction in HTFs. The results indicated that ZnO nanoparticles can efficiently inhibit HTFs proliferation, elevate ROS production level, and induce cell cycle arrest at G2/M phase, leading to HTFs apoptosis. ZnO nanoparticles can also decrease the expressions of TGF-β1, ED-A, and PICP at mRNA and protein levels; significantly prevent fibroblast-mediated collagen lattice contraction. Taken together, ZnO nanoparticles can efficiently ameliorate collagen lattice contraction in HTFs, and may be a promising antifibrotic agent in glaucoma filtration surgery. Our findings provide a new insight on anti-scar formation after glaucoma filtration surgery by using ZnO nanoparticles. ZnO nanoparticles could inhibit HTFs migration and proliferation, elevate the levels of LDH, ROS and cytochrome c, and induce cell cycle arrest at G2/M phase. Exposure of HTFs to ZnO nanoparticles could also decrease TGF-β1, ED-A, and PICP at mRNA and protein levels, and thus ameliorate collagen lattice contraction, thereby preventing scarring formation after glaucoma filtration surgery. Image 1 • Exposure of HTFs to ZnO nanoparticles can generate excessive ROS. • ZnO nanoparticles can inhibit HTFs proliferation in vitro. • ZnO nanoparticles induce G2/M cell cycle arrest and apoptosis in HTFs. • ZnO nanoparticles decrease the levels of TGF-β1, ED-A, and PICP expressions. • ZnO nanoparticles ameliorate fibroblast-mediated collagen lattice contraction. [ABSTRACT FROM AUTHOR]