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Ultraviolet-curable polyurethane acrylate (PUA) materials can be used in a number of important applications spanning from microfluidics, surface patterning to wearable technology. For the first time, the potential of encapsulation of modified zirconia (ZrO 2 ) nanoparticles is reported in PUA-based hybrid films aimed to facilitate profoundly enhanced hardness and refractive index. By successfully manipulating the interfacial reaction conditions between ZrO 2 nanoparticles and PUA film, the PUA-based nanocomposites exhibit an ultrahigh hardness of 9 and superior refractive index of 1.64 (589.3 nm). The outcomes obtained pave the way for seamless application of nanozirconia/PUA as a potent encapsulating material that provides structurally morphable, water resistant, and optically transparent light emitting diodes toward wearables devices in healthcare., (© 2021 Wiley-VCH GmbH.)

In the present study, we devised a green-synthesis route to NaYF 4 :Gd 3+ ,Yb 3+ ,Er 3+ upconversion nanoparticles (UCNPs) by using eco-friendly paraffin liquid, instead of 1-octadecene, as a high boiling non-coordinating solvent. A multifunctional nanoplatform was then developed by coating UCNPs with biocompatible transferrin (TRF) for magnetically-assisted and near-infrared light induced photodynamic therapy and bioimaging. Protoporphyrin IX (PpIX), a clinically approved photodynamic therapy agent, was loaded into the shell layer of the TRF-coated UCNPs (UCNP@TRF nanoparticles), which can be efficiently taken up by cancer cells for photodynamic therapy. Upon near-infrared light irradiation, the UCNP@TRF-PpIX nanoparticles could not only kill the cancer cells via photodynamic therapy but also serve as imaging probes. We also demonstrated that an external magnetic field could be used to increase the uptake of UCNP@TRF-PpIX nanoparticles by MDA-MB-231 and HeLa cancer cells, and hence result in an enhanced photodynamic therapy efficiency. This work demonstrates the innovative design and development of high-performance multifunctional PDT agents.

Aberrant methylation of the transcription factor AP-2 epsilon (TFAP2E) has been attributed to 5-fluorouridine (5-FU) sensitivity. 5-Aza-2'-deoxycytidine (DAC), an epigenetic drug that inhibits DNA methylation, is able to cause reactive expression of TFAP2E by demethylating activity. This property might be useful in enhancing the sensitivity of cancer cells to 5-FU. However, the effect of DAC is transient because of its instability. Here, we report the use of intelligent gelatinases-stimuli nanoparticles (NPs) to coencapsulate and deliver DAC and 5-FU to gastric cancer (GC) cells. The results showed that NPs encapsulating DAC, 5-FU, or both could be effectively internalized by GC cells. Furthermore, we found that the NPs enhanced the stability of DAC, resulting in improved re-expression of TFAP2E. Thus, the incorporation of DAC into NPs significantly enhanced the sensitivity of GC cells to 5-FU by inhibiting cell growth rate and inducing cell apoptosis. In conclusion, the results of this study clearly demonstrated that the gelatinases-stimuli NPs are an efficient means to simultaneously deliver epigenetic and chemotherapeutic drugs that may effectively inhibit cancer cell proliferation., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Process intensified synthetic approach for synthesizing gadolinium and cerium co‐doped yttrium aluminum garnet (GdYAG:Ce) phosphors in white light‐emitting diodes (wLED) is developed. By using a high‐gravity rotating packed bed (RPB) reactor for preparation of sol–gel precursors, the significantly enhanced molecular mixing allows precise control and tuning of dry gel with designed structure to obtain nanosized particles of GdYAG:Ce precursors, which are prone to low temperature quick sintering process and therefore reduce the energy consumption of the electric furnace 76% compared to solid phase method. By analyzing the effect of cycling times and high gravity levels of RPB reactor on sintering and crystallization, sintering condition for emission spectrum adjustable GdYAG:Ce phosphors is optimized. Prototype devices based on blue chips and GdYAG:Ce phosphors exhibit high color rendering index of 83.8 and low correlation color temperature of 5357 K that are beneficial for creating a healthy and comfortable lighting environment. [ABSTRACT FROM AUTHOR]

Disperse dyes are poorly water‐soluble and difficult to stably disperse in an aqueous medium, which greatly limits their application in dyeing synthetic fibers. Micronization can solve this problem. Herein, a facile way to prepare stable aqueous nanodispersions of disperse dye (C.I. disperse yellow 54) is presented by combining high‐gravity antisolvent precipitation in a rotating packed bed (RPB) with spray drying. The as‐prepared product had an average particle size of 120 nm, which could be readily redispersed in water. Compared with raw dye, the wettability and dispersibility of disperse dye nanoparticles were remarkably improved. Furthermore, the dyeing properties of the nanodispersions were obviously better than those of the commercial dye, which was micronized by ball milling. [ABSTRACT FROM AUTHOR]

Polyhedral oligomeric silsesquioxane (POSS)-coated nanodiamonds (NDs@POSS) were prepared via the amide formation between amine-functionalized POSS and oxygen-containing groups of NDs. The POSS structures grafted on the surface of NDs enable the NDs@POSS nanocomposites to be well-dispersed in organic solvents and polymers for multifunctional applications. The surface coating of NDs with POSS also bring other incidental advantages such as enhanced thermal stability and superhydrophobic of the NDs. NDs@POSS nanocomposites-embedded hybrid films based on polycarbonate and polyvinyl butyral were fabricated by solution blending methods, showing tunable refractive indexes in the range of 1.49-1.61. Furthermore, the powders of NDs@POSS were superhydrophobic with contact angle of water/air of 154°. Liquid marbles formed by coating the water droplet with NDs@POSS were prepared, and the process intensification effects of the NDs@POSS-based miniature reactors for degradation of methylene and fabrication of Ag nanoparticles were also demonstrated, respectively. [ABSTRACT FROM AUTHOR]

Ciprofloxacin (CIP) has been widely used to treat many types of bacterial infections. Herein, we reported a green approach for preparation of CIP nanoparticles via solvent anti-solvent precipitation by using subcritical water-ethanol mixture as the solvent. The solubility of CIP in subcritical water-ethanol mixture (with various ethanol ratio of 0, 5, and 20 wt%) at the temperature range from 100 °C to 170 °C and constant pressure of 4 MPa were measured. The chemical structure of CIP was stable after processed in subcritical water-ethanol mixture at up to 170 °C, confirmed by Fourier transformed infrared analysis. The obtained solubility data of CIP were correlated using a modified Apelblat model and the results of the predicted solubility show good agreement with the experimental value. The nanonization of CIP via solvent anti-solvent precipitation process that used the tunable solvent power of subcritical water-ethanol mixture was conducted. Two kinds of no-ionic, hydrophilic polymer, including polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG), were introduced as stabilizers in the precipitation process to obtain CIP nanoparticle with improved dissolution rate. These results show that as-synthesized CIP nanoparticles are promising for oral administration of CIP drugs. [ABSTRACT FROM AUTHOR]

The preparation of monodispersed inorganic nanoparticles is of great interest for many applications. In this article, transparent oil dispersion of monodispersed amorphous CaCO3 nanoparticles with high concentration and long-term stability were controllably prepared by a reverse microemulsion method. The effects of the addition amount of extra minute water and (NH4)2CO3 as novel assistant promoter, reaction temperature, Ca(OH)2/CaO mole ratio were explored. The optimum synthesis conditions were achieved. The as-prepared transparent oil nanodispersion had a good monodispersity, a uniform particle size of 8-10 nm, a high stability of over 12 months, a high solid content of 38 wt% (Ca content of about 15.5 wt%) and a high total base number of 416 mgKOH/g. The preparation process was further investigated by polarized optical microscope and Fourier transform infrared. This nanodispersion will find a promising applicability as an excellent nanodetergent in the fields of automobile and marine lubricants. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3663-3669, 2017 [ABSTRACT FROM AUTHOR]

We report a simple solution-based method to synthesize phase- and size-controllable ZnS nanoparticles at low temperature. Cubic ZnS (c-ZnS) and hexagonal ZnS nanoparticles (h-ZnS) were obtained by heating an aqueous solution of Zn(NO)·6HO and NaSO·5HO at different temperatures. When the system was heated at 65 °C for 24 h, hexagonal crystal structure of ZnS nanoparticles, with size of 50-350 nm, was obtained, as confirmed by X-ray diffraction and selected-area electron diffraction. When the reaction temperature was 100 °C under hydrothermal condition, c-ZnS nanoparticles were obtained and exhibited monodisperse nanoparticles with average size of 4 nm. Proper rate of S releasing tuned by the variation of pH value is believed to be critical to stabilize the hexagonal ZnS nanoparticles. Compared with large size of h-ZnS nanoparticles, c-ZnS nanoparticles show higher photocatalytic activity in degrading methyl orange (MO). The degradation efficiency of c-ZnS nanoparticles reaches 97% under UV irradiation for 120 min. The good ultraviolet absorbing ability, charge separation property, and large surface area of c-ZnS nanoparticles are believed to have a positive impact on improving the degradation rate and degradation efficiency of MO. [ABSTRACT FROM AUTHOR]

Oral beclomethasone dipropionate (BDP) has been extensively studied in the management of ulcerative colitis in clinical practice in recently years. However, the effective bioavailability and absorption of BDP are limited by its poor water solubility when administered orally. Herein, we report a green process for the synthesis of BDP nanoparticles via solvent anti-solvent precipitation, in which the subcritical water (SBCW) and cold water were used as the solvent and anti-solvent respectively. Polyethylene glycol (PEG), a non-ionic, hydrophilic polymer was introduced as stabilizers in the SBCW process to obtain sub-50 nm BDP nanoparticles with improved dissolution rate. Scanning electronic microscopy (SEM), Fourier transform infrared (FTIR) spectrophotometry, powder X-ray diffraction (XRD) and dissolution tests were performed to investigate the corresponding particle morphology, structure and dissolution rate properties of the BDP nanoparticles. The obtained BDP nanoparticles are < 50 nm in diameters with uniform distribution, exhibiting similar chemical structures, lower crystallinity and much higher dissolution rate than the raw BDP drug. These results show that as-synthesized BDP nanoparticles are promising for oral administration of BDP towards the management of ulcerative colitis. [ABSTRACT FROM AUTHOR]

Clarithromycin (CLA) is an important drug used to treat various bacterial infections, while its effective bioavailability is limited by the poor water-solubility of the CLA molecule. Subcritical water (SBCW) processes have been demonstrated to be a new promising alternative for the preparation of drug nanoparticles with enhanced dissolution rate. In this work, we reported ultrafine CLA nanoparticles via anti-solvent precipitation in subcritical water, with detailed studies on the effects of operating parameters. The corresponding particle morphology, and dissolution rate properties of the CLA nanoparticles were characterized through scanning electronic microscopy (SEM), Fourier transform infrared spectrophotometry (FT-IR), powder X-ray diffraction (XRD) and dissolution tests. Under optimized experimental conditions, which was using 1.5 mL of SBCW at 150 °C as the solvent and 15 of aqueous PVP solution (0.4 wt%) as the anti-solvent, uniform sub-50 nm sized CLA nanoparticles are obtained. According to the dissolution testing, the ultrafine CLA nanoparticles exhibit very high dissolution rate (over 85% at 60 min) compared with that of raw CLA (10% at 60 min). Our results suggest that as-synthesized ultrafine CLA nanoparticles via anti-solvent precipitation in subcritical water are promising for efficient therapy. [ABSTRACT FROM AUTHOR]

Abstract: Spinel ferrite Co x (Cu0.5Zn0.5)1−x Fe2O4 over a compositional range 0< x <1 was prepared using a simple hydrothermal method. Particle sizes could be varied from 14 to 25nm by changing the x value. X-ray diffraction results confirmed that all the as-prepared nanoparticles revealed typical spinel structure and transmission electron microscopy images showed that the particle size of the samples increased with increasing x value. The magnetic properties of the as-prepared Co x (Cu0.5Zn0.5)1−x Fe2O4 nanoparticles have been systematically examined. The maximum saturation magnetization existed at the highest Co content (x =1). The electromagnetic properties of all the samples have been measured by an Agilent network analyzer and the results showed that Co0.1(Cu0.5Zn0.5)0.9Fe2O4 possessed the best microwave absorbing properties. [ABSTRACT FROM AUTHOR]

Abstract: Co–Cu–Zn doped Fe3O4 nanoparticles can be successfully synthesized using a simple method. The particles in the size range 20−400nm with different regular shapes i.e. sphere-like, regular hexane and tetrahedron are controllably achieved by changing the metal ion concentration. Compared to pure Fe3O4 without dopants, Co–Cu–Zn doped Fe3O4 nanoparticles exhibit better microwave absorbing properties at 2−18GHz. Among three Co–Cu–Zn doped Fe3O4 nanoparticles with different morphologies, tetrahedral Co–Cu–Zn doped Fe3O4 nanoparticles represent a better dielectric loss in high frequency range. This work is believed the first known report of Co–Cu–Zn doped Fe3O4 nanoparticles with tunable morphology and magnetic properties through the hydrothermal process without using any organic solvents, organic metal salts or surfactants. [Copyright &y& Elsevier]

Abstract: Co0.2Cu0.03Fe2.77O4 nanoparticles with different morphologies have been synthesized directly via a simple hydrothermal method. The effects of pH value, precursor concentration, reaction temperature and surfactant on the particle size were discussed. X-ray diffraction analyses showed that the as-synthesized Co0.2Cu0.03Fe2.77O4 nanoparticles possessed typical spinel structure. Scanning electron microscope images showed different morphologies of the particles, including truncated octahedron and octahedron. It was indicated that well-dispersed Co0.2Cu0.03Fe2.77O4 nanoparticles can be synthesized at pH values ranging from 11 to 13, and reaction temperature of 160°C. The particle size decreased from 18 to 10nm after the addition of sodium dodecyl sulphate at the pH value of 9. The magnetic measurement showed that the as-prepared Co–Cu spinel ferrite nanoparticles possessed hard magnetic property. [Copyright &y& Elsevier]

The preparation of oil-soluble metal carbonate colloids is of interest in the area of lubricant additives. This study presents a novel mass-transfer intensified approach for efficient preparation of monodisperse CaCO 3 nanoparticles as overbased nanodetergents based on W/O microemulsion using a high-gravity rotating packed bed (RPB) reactor. The effects of high gravity level, gas-liquid ratio, gas and liquid flow rates were systematically investigated. The as-prepared products had good transparency, an average particle size of about 6 nm, a high storage stability of over 18 months, a solid content of 38.5 wt% and a highest total base number (TBN) of 417 mgKOH/g. As compared to conventional stirring tank reactor (STR), the product prepared in the RPB reactor had better monodispersity and stability, smaller average particle size, narrower size distribution and higher TBN. Furthermore, the RPB reactor had a greatly shortened carbonation reaction time from 120 min of STR to 53 min, increasing the production efficiency by about 56%. [ABSTRACT FROM AUTHOR]

Abstract: A facile hydrothermal method was developed for preparing copper–carbon core–shell structured particles through a reaction at 160°C in which glucose, copper sulfate pentahydrate and cetyltrimethylammonium bromide were used as starting materials. The original copper–carbon core–shell structured particles obtained were sized of 100–250nm. The thickness of carbonaceous shells was controlled ranging from 25 to 100nm by adjusting the hydrothermal duration time and the concentrations of glucose in the process. Products were characterized with transmission electron microscopy, X-ray diffraction, energy dispersive spectroscopy, Fourier transform infrared spectroscopy. Since no toxic materials were involved in the preparation, particles with stable carbonaceous framework and reactive surface also showed promising applications in medicine, electronics, sensors, lubricant, etc. [Copyright &y& Elsevier]

Abstract: ZnO nanoparticles were prepared by a simple chemical synthesis route. Subsequently, SiO2 layers were successfully coated onto the surface of ZnO nanoparticles to modify the photocatalytic activity in acidic or alkaline solutions. The obtained particles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS) and zeta potential. It was found that ultrafine core/shell structured ZnO/SiO2 nanoparticles were successfully obtained. The photocatalytic performance of ZnO/SiO2 core/shell structured nanoparticles in Rhodamine B aqueous solution at varied pH value were also investigated. Compared with uncoated ZnO nanoparticles, core/shell structured ZnO/SiO2 nanoparticles with thinner SiO2 shell possess improved stability and relatively better photocatalytic activity in acidic or alkaline solutions, which would broaden its potential application in pollutant treatment. [ABSTRACT FROM AUTHOR]

We report the synthesis of highly dispersible zirconia (ZrO 2) nanoparticles in sub-kilogram-scale by hydrothermal process coupled with alkaline hydrogen peroxide (AHP) treatment, with detailed studies on the effects of experimental parameters. Under optimized experimental condition, which was hydrothermal reaction at 110 °C for 6 h with mole ratio of sodium hydrate to zirconium carbonate basic in reactants as 2.3, pure-phase cubic-ZrO 2 nanoparticles are obtained. Followed by AHP treatment of the ZrO 2 nanoparticles at 50 °C for 5 h in 0.4 M hydrogen peroxide and 4 M sodium hydrate, the dispersibility of ZrO 2 nanoparticles in aqueous suspension was enhanced due to the introduced Zr-OH groups on the surface. ZrO 2 nanodispersion with solid content of 37 wt% in aqueous solution exhibited a uniform hydrodynamic size of 14.15 ± 5.834 nm and was stable for over six months without significant aggregates. Transparent hybrid optical resins with tunable refractive index in the range of 1.55–1.71 were prepared by solution blending method using ZrO 2 nanoparticles as composite fillers in polyvinyl alcohol substrate. Compared with pure polyvinyl alcohol resin, the hybrid resin exhibits significant enhanced mechanical properties. Sub-kilogram-scale preparation of highly aqueous dispersible ZrO 2 nanoparticles offers possibility for practical applications. Unlabelled Image • A scalable method for synthesis of highly dispersible zirconia nanoparticles • ZrO 2 nanodispersion with solid content of 37 wt% was stable for over six months. • The refractive index of transparent hybrid resins was tunable between 1.55 and 1.71. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Process of miniemulsion polymerization was intensified by high gravity technology. • Waterborne polyurethane nanoparticles were prepared with an average size of 137 nm. • The nanodispersion were stable for up to one month with no sediments observed. • Fluorescent nanodispersion of AIEgens loaded polyurethane (AIEgens@PU) is prepared. • The AIEgens@PU nanodispersion are promising for multifunctional applications. Abstract Polymer encapsulated fluorescent nanoparticles have found many applications in bioimaging, fluorescent gels and inks. However, their translation into the practical products has been slow because it is still difficult to produce nanoparticles that are consistent "batch-to-batch" for scale-up. Herein, we develop a high-gravity miniemulsion polymerization route for fluorescent waterborne polyurethane (PU) by using rotating packed bed (RPB) reactor for process intensification. In optimized conditions, the PU nanoparticles obtained exhibited an average size of 137 nm with narrow size distribution. Dispersion stability of the PU nanodispersions was investigated and no significant sediments or aggregates were observed for up to one month. The 1,1,2,3,4,5-hexaphenylsilole dyes, a kind of typical aggregation-induced emission luminogens (AIEgens), could be in situ loaded in PU nanoparticles, forming fluorescent nanodispersions of AIEgens@PU in aqueous solution. The preliminary applications of AIEgens@PU nanodispersion for in vitro fluorescent labeling of cells, transparent fluorescent films and anti-counterfeit printing inks were demonstrated. This study demonstrated that the newly developed high-gravity miniemulsion polymerization method provides an effective route to waterborne PU nanodispersion for multifunctional applications. [ABSTRACT FROM AUTHOR]

Abstract: Docetaxel (DOC) is widely used as radiosensitizer in various tumors, including gastric cancer (GC), but its therapeutic effect remains to be improved. In this study, using docetaxel-loaded nanoparticles (DOC-NPs) based on gelatinase-stimuli strategy, we compared their radioenhancement efficacy with docetaxel in GC. Compared with DOC, radiosensitization of DOC-NPs was improved significantly (sensitization enhancement ratio increased 1.09-fold to 1.24-fold, P <0.01) in all three gelatinase overexpressing GC cells, while increased slightly (1.02-fold, P =0.38) in gelatinase deficient normal gastric mucosa cells. The improved radiosensitization efficacy was associated with enhanced G2/M arrest, increased reactive oxygen species (ROS), more effective DSBs and promoted apoptosis. More importantly, the radiosensitization efficacy of DOC-NPs (estimated as ‘‘very active’’) was more prominent than DOC (estimated as ‘‘moderately active’’) by intravenous injection in xenograft. In conclusion, DOC-NPs are highly selective radiosensitizers in gelatinase over-expressing tumors, and more effective than DOC. By manipulating the common microenvironment difference between tumor and normal tissue, gelatinase-mediated nanoscale delivery system serves as a potential strategy possessing both universality and selectivity for radiosensitizers. [Copyright &y& Elsevier]

Deep-ultraviolet (DUV) light devices are receiving widely attention due to their potential use in sterilization and water purification, in particularly, during the COVID-19 pandemic. Photoluminescence detectors that demonstrate the existence of DUV light invisible to our eyes are of importance. Herein, we propose a process intensified approach via high-gravity reactive precipitation combined with hydrothermal synthesis for production of Mn2+ doped zinc orthogermanate (Zn 2 GeO 4 : Mn2+) nanophosphors for deep-ultraviolet detecting. The rotating packed bed (RPB) was used as the reactor for process intensification of the reactive precipitation and the whole processing time was significantly reduced. The Zn 2 GeO 4 : Mn2+ phosphors show green emission upon ultraviolet or near ultraviolet excitation. In optimized conditions, the products show a sub-microrod morphology with average size of about 200 nm. Under the excitation of 254 nm light, the Zn 2 GeO 4 : Mn2+ nanophosphors exhibit bright green emission at peak wavelength of 535 nm. [ABSTRACT FROM AUTHOR]