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The development of environmental-friendly self-healing nanocomposites has attracted much attention. In this paper, the light-activated cellulose nanocrystals/ fluorinated polyacrylate-based waterborne coating based on the reversible cycloaddition reaction of the coumarin groups was prepared via Pickering emulsion polymerization. The cellulose nanocrystals (CNCs) modified by the PDMAEMA-b-PGMA-b-P(HFBA-co-VBMC) copolymer were studied via FT-IR and TGA. In addition, the dispersity and interface behavior of CNCs before and after modification were investigated by DLS and interfacial tension measurements. Afterwards, we focused on the influence of modified CNCs, PDMAEMA-g-CNC-g- P(HFBA-co-VBMC) (MCNC) dosage on the Pickering emulsion, emulsion polymerization and properties of latex film. The droplet diameter of Pickering emulsion gradually reduced with the increase of MCNC dosage. The MCNC dosage for the minimum average size and optimum stability of latex particles was 1.0 wt%. Moreover, the latex film comprising 1.0 wt% MCNC presented not only high tensile stress (6.0 MPa), large elongation at break (567.70 %) and superior oil/water repellency but also excellent self-healing properties. The outstanding self-healing capability of latex film was attributed to the reversible light-activated dimerization of coumarin groups. The preparation method for the advanced performance waterborne cellulose nanocrystals/fluorinated polyacrylate will provide valuable guidance for the development of versatile materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Herein, an oxygen defect-modulated zinc oxide sonosensitizer is designed, which enhances the absorbance of ultrasound energy and suppresses the recombination of ultrasound-initiated electrons and holes to promote reactive oxygen species yield. It achieves a high tumor inhibition efficiency of 79.9%, which exhibits a potential application for sonodynamic cancer therapy.

The endocrine system's interference caused by environmental estrogens (EEs) residue in food is a topic of public concern. Here, we construct an aptasensor for the sensitive detection of EEs based on luminescence resonance energy transfer (LRET). With MoS 2 nanosheets acting as the energy acceptor and upconversion luminescence nanoparticles@gold nanoparticles (UCNPs@Au) as the luminescence donor, autofluorescence from food is prevented from interfering. The in-situ deposition of AuNPs not only induces local field enhancement to significantly increase the luminescence intensity of UCNPs, but also conduces to the modification of aptamer through Au-S bond. This aptasensor can respond to multiple estrogens thanks to the choice of a universal aptamer that recognizes phenolic hydroxyl group, and it offers the probability to screen unidentified phenolic estrogens. This method has a high sensitivity and a low limit of detection (LOD), and the satisfactory recovery rates acquired from water and milk samples confirmed its considerable application value., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Calcium phosphates (CaP) represent an impressive kind of biomedical material due to their excellent biocompatibility, bioactivity, and biodegradability. Their morphology and structure highly influence their properties and applications. Whilst great progress has been made in research on biomedical materials, there is still a need to develop a method that can rapidly synthesize and screen micro/nanosized biomedical materials. Here, we utilized a microarray screening platform that could provide the high-throughput synthesis of biomedical materials and screen the vital reaction conditions. With this screening platform, 9 × 9 sets of parallel experiments could be conducted simultaneously with one- or two-dimensions of key reaction condition gradients. We used this platform to establish a one-dimensional gradient of the pH and citrate concentration and a two-dimensional gradient of both the Ca/P ratio and pH to synthesize CaP particles with various morphologies. This screening platform also shows the potential to be extended to other reaction systems for rapid high-throughput screening.

Cellulose nanocrystals/fluorinated polyacrylate soap-free emulsion was successfully synthesized via RAFT-assisted Pickering emulsion process using modified cellulose nanocrystals as particle stabilizers. The cellulose nanocrystals were organically modified by linear triblock copolymer poly(2-(dimethylamino) ethyl methacrylate)-b-poly(glycidyl methacrylate)-b-poly(2,2,3,4,4,4-Hexafluorobutyl acrylate) (PDMAEMA-b-PGMA-b-PHFBA) with reactive trithiocarbonate group. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses showed that modified cellulose nanocrystals were armored on the surface of spherical particles. The morphology and particle size of the resulting products depended on the pH value of particle dispersion. When the value of pH increased from 1.06 to 2.97, the spherical-like particles size decreased from 763 nm to 253 nm. However, with pH value increasing to 6.85, the particle size increased to 394 nm. Furthermore, a possible mechanism for the formation of the cellulose nanocrystals/fluorinated polyacrylate nanoparticles with core-shell structure was proposed., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: In the past decade, trackable smart drug delivery systems have played important roles in the treatment of many diseases such as cancer because the drug carriers can be visualized through their distinct physical properties. However, it is still difficult to achieve precise drug delivery because such systems usually rely on a single imaging system., Aim: This study aimed to present a novel type of multimodality imaging-guided strategy to visualize the drug carriers of eccentric magnetic microcapsule (EMM) designed for potential treatment of hepatocellular carcinoma (HCC)., Method and Results: The EMMs were prepared by using a three-phase microfluidic device. The as-prepared EMMs embedded with Fe 3 O 4 nanoparticles are magnetic, with high density and acoustic impedance, allowing for visualization by magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound (US) imaging during local injection. The release of drug from these EMMs can be further controlled by an external electromagnetic field (EMF). As a proof of concept, we demonstrated the process of multimodality imaging to guide local injection and the controlled release of doxorubicin (DOX) from the EMMs in a phantom. We showed that the release rate of DOX was directly correlated to the strength of the EMF. In addition, we cocultured green fluorescent protein (GFP)-transfected HeLa cancer cells with the DOX-loaded EMMs and documented their apoptosis by DOX following the release triggered by EMF., Conclusion: The results suggest that these EMMs serve both as contrast agents that can be visualized by multimodality imaging techniques and as smart drug delivery systems, with great potential for precision medicine., (© 2018 Wiley Periodicals, Inc.)

Microfluidic chips combined with surface-enhanced Raman spectroscopy (SERS) offer an outstanding platform for rapid and high-sensitivity chemical analysis. However, it is nontrivial to conveniently form nanoparticle aggregrates (as SERS-active spots for SERS detection) in microchannels in a well-controlled manner. Here, we present a rapid, highly sensitive and label-free analytical technique for determining bovine serum albumin (BSA) on a poly(dimethylsiloxane) (PDMS) microfluidic chip using SERS. A modified PDMS pneumatic valve and nanopost arrays at the bottom of the fluidic microchannel are used for reversibly trapping gold nanoparticles to form gold aggregates, creating SERS-active spots for Raman detection. We fabricated a chip that consisted of a T-shaped fluidic channel and two modified pneumatic valves, which was suitable for fast loading of samples. Quantitative analysis of BSA is demonstrated with the measured peak intensity at 1,615 cm(-1) in the surface-enhanced Raman spectra. With our microfluidic chip, the detection limit of Raman can reach as low as the picomolar level, comparable to that of normal mass spectrometry.

In this study we described the nanocomposites films of specially synthesized inorganic Prussian blue (PB) nanoparticles and polyoxocation Al(13) Keggin ions that possess the excellent sensing activities. Film fabrication using layer-by-layer (LBL) self-assembly technique was followed by electrochemical characterization. The assembled multilayer Al(13)/PB films as sensor devices for both the catalytic reduction of H(2)O(2) and detecting the change of relative humidity were also investigated. The sensitivity of the biosensor was 0.886 mA cm(-2)mM(-1), and about two orders of magnitude change in resistance was observed as the relative humidity increasing from 5 to 95%. Both sensors exhibited good reproducibility, wide linear range. The performance and multifunctional abilities of these nanocomposites promise potential applications in biosensors, environmental controlling system and biomedical devices.

Cation-associated cytotoxicity limits the systemic administration of RNA delivery in vivo , demanding the development of non-cationic nanosystems. In this study, cation-free polymer-siRNA nanocapsules with disulfide-crosslinked interlayer, namely T-SS(-), were prepared via the following steps: 1) complexation of siRNA with a cationic block polymer cRGD-poly(ethylene glycol)- b -poly[(2-aminoethanethiol)aspartamide]- b -poly{ N' -[ N -(2-aminoethyl)-2-ethylimino-1-aminomethyl]aspartamide}, abbreviated as cRGD-PEG-PAsp(MEA)-PAsp(C=N-DETA), 2) interlayer crosslinking via disulfide bond in pH 7.4 solution, and 3) removal of cationic DETA pendant at pH 5.0 via breakage of imide bond. The cationic-free nanocapsules with siRNA cores not only showed great performance (such as efficient siRNA encapsulation, high stability in serum, cancer cell targeting via cRGD modification, and GSH-triggered siRNA release), but also achieved tumor-targeted gene silencing in vivo. Moreover, the nanocapsules loaded with siRNA against polo-like kinase 1 (siRNA-PLK1) significantly inhibited tumor growth without showing cation-associated toxicity side effects and remarkably improved the survival rate of PC-3 tumor-bearing mice. The cation-free nanocapsules could potentially serve as a safe and effective platform for siRNA delivery. Cation-associated toxicity limits the clinical translation of cationic carriers for siRNA delivery. Recently, several non-cationic carriers, such as siRNA micelles, DNA-based nanogels, and bottlebrush-architectured poly(ethylene glycol), have been developed to deliver siRNA. However, in these designs, siRNA as a hydrophilic macromolecule was attached to the nanoparticle surface instead of being encapsulated. Thus, it was easily degraded by serum nuclease and often induced immunogenicity. Herein, we demonstrate a new type of cation-free siRNA-cored polymeric nanocapsules. The developed nanocapsules not only showed capacities including efficient siRNA encapsulation, high stability in serum, and cancer cell targeting via cRGD modification, but also achieved an efficient tumor-targeted gene silencing in vivo. Importantly, unlike cationic carriers, the nanocapsules exhibited no cation-associated side effects. [Display omitted] [ABSTRACT FROM AUTHOR]

Ag/fluorine-containing polyacrylate latex was successfully synthesized via Pickering emulsion polymerization using Ag/poly(2-dimethylaminoethyl methacrylate-co-hexafluorobutyl acrylate) (Ag/P(DMAEMA-co-HFBA)) hybrid micelles as particle emulsifiers. The influences of introducing the Ag nanoparticles (NPs) component and the concentration of Ag/P(DMAEMA-co-HFBA) hybrid micelles on emulsion polymerization and finished cotton fabric properties were studied. The results showed that the Ag/fluorine-containing polyacrylate latex had a higher conversion, smaller particle size than the fluorine-containing polyacrylate latex using P(DMAEMA-co-HFBA) micelles as emulsifiers, indicating the positive effect of Ag NPs on emulsion polymerization. And thermogravimetric analysis (TGA) proved that Ag NPs improved the thermal stability of the latex film. Moreover, the surface of the cotton fabric finished by Ag/fluorine-containing polyacrylate latex showed more rough morphology, better hydrophobicity and excellent antibacterial activity owing to the synergistic effect of the cationic fluorine-containing polyacrylate compounds and Ag nanoparticles. Meanwhile, the presence of Ag NPs also improved the tensile strength of the finished cotton fabric, but reduced slightly the whiteness. When the concentration of Ag/P(DMAEMA-co-HFBA) hybrid micelle emulsifier was 8 mg/mL, the Ag/fluorine-containing polyacrylate latex particles presented regular raspberry-shaped with an average diameter of 120 nm, and the water/oil contact angles of finished cotton fabric attained 145° and 90°, respectively. In addition, the finished cotton fabric exhibited excellent antibacterial properties against both S. aureus and E. coli as the concentration of Ag/P(DMAEMA-co-HFBA) hybrid micelles was 12 mg/mL. The mechanism for the formation of Ag/fluorine-containing polyacrylate latex was proposed. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystal-dressed fluorinated polyacrylate latex particles were prepared via RAFT-mediated Pickering emulsion polymerization using cellulose nanocrystals (CNCs) modified with amphiphilic polymers as Pickering stabilizers. The main work was to study the effect of pH value and the amount of fluorinated monomer on emulsion polymerization and finished fabric properties. The monomer conversion increased first and then decreased as the pH and the amount of fluorine monomer increased, while a reverse trend was noted for the particle size and particle size distribution. The results obtained from TEM verified that the latex particles presented a spher-like mophology with a well-defined core–shell structure. 1H-NMR and FT-IR spectroscopy were employed to study the chemical structure of cellulose nanocrystal-dressed fluorinated polyacrylate latex particles. The SEM and EDX analysis indicated that cellulose nanocrystal-dressed fluorinated polyacrylate latex particles were successfully adhered to the fiber surface and the finished fabric presented a relatively rough surface morphology. The contact angle results exhibited the finished fabric had excellent water and oil resistance. [ABSTRACT FROM AUTHOR]

• Flame suppression mechanism of nano PMMA dust explosion by KHCO 3 was investigated. • The effect of KHCO 3 particle size on the physical suppression mechanism was analyzed. • A numerical model was established to reveal chemical suppression mechanism. Flame suppression mechanism of KHCO 3 for 100 nm PMMA dust explosions was investigated experimentally and computationally. The effect of KHCO 3 particle size on the suppression efficiency was examined. The study revealed that the larger the proportion of added KHCO 3 , the more significant the suppression effect on flame, for KHCO 3 particles with a fixed particle size distribution. The suppression effects were significantly increased with the decreasing of KHCO 3 particle size distributions. For endothermic mechanism, when the KHCO 3 particles with three particle sizes were mixed with 100 nm PMMA, the heat absorption peaks exhibited at the initial stage, in which the heat absorption values were 28 J/g, 26 J/g and 21 J/g, respectively. A kinetics model was established to reveal the chemical suppression mechanism. It was presented that the mole fractions of key flame radicals (H and OH) were obviously reduced during the chain reaction processes with the addition of KHCO 3. For KHCO 3 particles, the formation of catalytic cycle K ⇔ KOH converted H and OH radicals into a stable combustion product H 2 O, resulting in a lower flame speed and flame temperature. [ABSTRACT FROM AUTHOR]

A family of biheterocyclic energetic materials based on 1,3‐diazocyclopentane were synthesized and characterized by IR, NMR, MS, and elemental analysis. The crystal structures of compounds 8 and 9 were determined by single‐crystal X‐ray diffraction. Heats of formation, detonation properties were calculated by isodesmic reactions and Kamlet–Jacobs equations, respectively. The safety parameters associated with impact sensitivity and friction sensitivity were also investigated. It is noteworthy that compounds 5 and 6 possess excellent detonation properties (detonation velocities were 8.89 and 8.66 km s–1; detonation pressures were 35.8 and 32.7 GPa, respectively) and acceptable sensitivities (impact sensitivities were 10 and 13 J; friction sensitivities were 103 and 87 N, respectively). In addition, electronic properties (such as frontier molecular orbitals, electronic densities and electrostatic potentials) of compounds 5 and 6 were also simulated accurately to give an assessment of their physicochemical properties. A series of 1,3‐diazocyclopentane based energetic materials were synthesized and their properties were investigated. Compounds 5 and 6 were finally selected as promising candidates for high energy density materials and their frontier molecular orbitals, electronic densities, and electrostatic potentials were simulated [ABSTRACT FROM AUTHOR]

The direct laser initiation of 2,4,6,8,10,12‐hexanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane (CL‐20) doped with aluminum nanoparticles was conducted using a short laser pulse of Nd:YAG (1064 nm wavelength, 14 ns duration) through a 1 mm diameter optical fiber. The effects of aluminum nanoparticles on thermal stability, light absorption, and laser initiation energy were investigated. Results revealed that the aluminum nanoparticles significantly enhanced the absorption of light and decreased the laser initiation energy. The laser initiation energy, which was higher than 1000 mJ for an undoped CL‐20, could be reduced to 80, 40, 30, 30, and 20 mJ by adding 0.2 %, 0.5 %, 1.0 %, 2.0 %, and 5.0 % aluminum nanoparticles, respectively. When a short pulse laser was radiated on the surface of the explosives, the aluminum nanoparticles absorbed the laser energy, heated, and reached high temperatures, resulting in hotspot formation and detonation. The direct laser initiation of doped CL‐20 with a short laser pulse and a low energy through an optical fiber would contribute to the manufacture of small, safe, and reliable laser detonators. [ABSTRACT FROM AUTHOR]

Nano-SiO2/polysiloxane modified polyacrylate emulsifier-free emulsion was synthesized by emulsion polymerization using surfmer and the sol-gel process. The cocondensation of trimethoxysilyl groups of the polyacrylate polymer and TEOS formed a cross-linking network film, in which the nanometer-size silica particles were dispersed homogeneously in the acrylic polymer component. The hybrid films were transparent, solvent-resistant, good thermal stability and mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract: This work aims at developing the synergetic catalysis of rare earth oxides, which can serve as the anchoring sites for Pt and in turn as the active sites for the methanol electro-oxidation. Ordered mesoporous carbon has been modified with RE2O3 (RE=Sm, Eu and Gd) and subsequently deposited with Pt nanoparticles by a microwave heating process. The catalytic activities for methanol electro-oxidation are evaluated by cyclic voltammogram, chronoamperometry and electrochemical impedance spectroscopy. Pt/C-Sm2O3 exhibits an improvement on dispersion and electrocatalytic performance, with the highest mass activity (145.1mAmg−1) as well as good stability. A possible mechanism is proposed for the effect of RE2O3 on Pt nanoparticles. The adsorbed hydroxyl species supplied by RE2O3 in the support are contributed to the release of Pt active sites through CO removal and therefore promote the catalytic activity spontaneously. [Copyright &y& Elsevier]

Abstract: Ordered mesoporous carbon with large porosity was surface-modified with PrO x and subsequently deposited with Pt nanoparticles by microwave heating. Transmission electron microscopy images indicated that PrO x could improve the dispersion of Pt nanoparticles. The electrocatalytic activity of Pt catalysts was evaluated according to hydrogen adsorption region of cyclic voltammograms and electrochemical impedance spectroscopy. Pt/C–PrO x exhibited excellent performance in H2SO4, with a larger electrochemical active area and lower charge-transfer resistance than that of Pt/C. It is mainly due to enhanced dispersion of Pt nanoparticles and improved hydrogen adsorption on support. [Copyright &y& Elsevier]

Highlights from the article: Erratum: Initiation of CL-20 Doped with Aluminum Nanoparticles by Using a Laser Pulse through an Optical Fiber Optical fiber, CL-20, Laser initiation, Detonator, Aluminum nanoparticle.