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The healing of chronic diabetic wounds remains a formidable challenge in modern times. In this study, a novel traditional Chinese medicine microneedle patch was designed based on the physiological characteristics of wounds, with properties including hemostasis, anti-inflammatory, antioxidant, antimicrobial, and induction of angiogenesis. Initially, white peony polysaccharide (BSP) with hemostatic properties and carboxymethyl chitosan (CMCS) with antimicrobial capabilities were used as materials for microneedle fabrication. To endow it with antimicrobial, procoagulant, and adhesive properties. Among them, loaded with ROS-sensitive nanoparticles of Astragalus polysaccharides (APS) based on effective components baicalein (Bai) and berberine (Ber) from Scutellaria baicalensis (SB) and Coptis chinensis (CC) drugs (APB@Ber). Together, they are constructed into multifunctional traditional Chinese medicine composite microneedles (C/B@APB@Ber). Bai and Ber synergistically exert anti-inflammatory and antimicrobial effects. Microneedle patches loaded with BSP and APS exhibited significant effects on cell proliferation and angiogenesis induction. The combination of composite polysaccharides enabled the microneedles to adhere stably to wounds and provide sufficient strength to penetrate the biofilm and induce dispersion. The combination of composite polysaccharides enabled the microneedles to adhere stably to wounds and provide sufficient strength to penetrate the biofilm and induce dispersion. Therefore, traditional Chinese medicine multifunctional microneedle patches offer potential medical value in promoting the healing of diabetic wounds., 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 © 2024 Elsevier Ltd. All rights reserved.)

Achyranthes plays the role of dredging the meridians and clearing the joints with a certain anti-inflammatory effect, peripheral analgesic activity and central analgesic activity. A novel self-assembled nanoparticles containing Celastrol (Cel) with matrix metalloproteinase (MMP)-sensitive chemotherapy-sonodynamic therapy was fabricated targeting macrophages at the inflammatory site of rheumatoid arthritis. Dextran sulfate (DS) with highly expressed SR-A receptor on the surface of macrophages is used to specifically target the site of inflammation; by introducing PVGLIG enzyme-sensitive polypeptides and ROS-responsive bonds, it can achieve the desired effect on MMP-2/9 and reactive oxygen species at the joint site. The preparation forms DS-PVGLIG-Cel&Abps-thioketal-Cur@Cel nanomicelles, referred to as D&A@Cel. The resulting micelles had an average size of 204.8 nm and the zeta potential -16.46 mV. The results show that activated macrophages can effectively capture Cel in in vivo experiments, indicating that Cel delivered by nanoparticles can significantly improve bioavailability., 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. Published by Elsevier B.V.)

Metabolic syndromes are a group of metabolic disorders for which the molecular mechanisms are still unclear. An increasing number of studies have implicated metabolic syndrome in the association with inflammation. Currently, lipsomes is known to improve nanoparticle hydrophobicity. Meanwhile, in drug delivery systems the application of cholesterol, which is commonly used to stabilise liposomal structures, has essentially no pharmacological effect on liposomes. Herein, we developed an 'anti-inflammatory liposome' (Phy-Lip) to effectively handle these challenges via employing Phytosterol instead of cholesterol. Different with the conventional liposomes, Phy-Lip is a much more brilliant nanoparticle with anti-inflammatory functions. In Phy-Lip, cholesterol was substituted by Phy, which works as membrane stabiliser, anti-inflammatory adjuvant at the same time. The experimental results show that Phy-Lip has a strong anti-inflammatory effect, and improves Metabolic syndromes. This study aims to provide a way to solve the challenge.

Recessive dystrophic epidermolysis bullosa (RDEB) is a severe congenital skin fragility disease caused by COL7A1 mutations that result in type VII collagen (C7) deficiency. Herein, we report a synergistic polyplex system that can efficiently restore C7 expression in RDEB keratinocytes. A highly branched multifunctional poly(β-amino ester) (HPAE), termed as HC32-122, was optimized systematically as the high-performance gene delivery vector for keratinocytes, achieving much higher transfection capability than polyethylenimine, SuperFect, and Lipofectamine 2000 without inducing obvious cytotoxicity. Concurrently, a 12 kb length minicircle DNA encoding ∼9 kb full-length COL7A1 (MCC7) devoid of bacterial sequence was biosynthesized as the therapeutic gene. Combining the highly potent polymer and the miniaturized gene structure, HC32-122/MCC7 polyplexes achieve 96.4% cellular uptake efficiency, 4019-fold COL7A1 mRNA enhancement, and robust recombinant C7 expression. Structure-property investigations reveal that HC32-122 can effectively condense MCC7 to form small, uniform, compact, and positively charged spherical nanoparticles with high DNA release flexibility. Moreover, formulation study shows that sucrose is conductive to lyophilized HC32-122/DNA polyplexes for maintaining the transfection capability. Direct frozen polyplexes can maintain full gene transfection capability after one-year storage. High efficiency, biocompatibility, facile manipulation, and long-term stability make the HC32-122/MCC7 system a promising bench-to-bed candidate for treating the debilitating RDEB.

Drug-loaded injectable hydrogels have been proven to possess huge potential for applications in tissue engineering. However, increasing the drug loading capacity and regulating the release system to adapt to the microenvironment after myocardial infarction face a huge challenge. In this research, an ROS-sensitive injectable hydrogel strengthened by self-nanodrugs was constructed. A hyperbranched ROS-sensitive macromer (HB-PBAE) with multiacrylate end groups was synthesized through dynamic controlled Michael addition. Meanwhile, a simple protocol based on dopamine polymerization was employed to generate a polydopamine (PDA) layer deposited on the tanshinone IIA (TIIA) nanoparticles (NPs) formed from spontaneous hydrophobic self-assembly. The HB-PBAE reacted with thiolate-modified hyaluronic acid (HA-SH) to form an in situ hydrogel, where TIIA@PDA NPs can be conveniently entrapped through the chemical cross-link between thiolate and quinone groups on PDA, which doubles the modulus of hydrogels. The in vivo degradation behavior of the hydrogels was characterized by MRI, exhibiting a much slower degradation behavior that is markedly different from that of in vitro. Importantly, a significant improvement of cardiac functions was achieved after hydrogel injection in terms of increased ejection fraction and decreased infarction size, accompanied by inhibition of the expression of inflammation factors, such as IL-1β, IL-6, and TNF-α.

Ischemic stroke is one of the major leading causes for long-term disability and mortality. Collateral vessels provide an alternative pathway to protect the brain against ischemic injury after arterial occlusion. Aiming at visualizing the collaterals occurring during acute ischemic stroke, an integrin α v β 3 -specific Fe 3 O 4 -Arg-Gly-Asp (RGD) nanoprobe is prepared for magnetic resonance imaging (MRI) of the collaterals. Rat models are constructed by occluding the middle cerebral artery for imaging studies of cerebral ischemia and ischemia-reperfusion on 7.0 Tesla MRI using susceptibility-weighted imaging sequence. To show the binding specificity to the collaterals, the imaging results acquired with the Fe 3 O 4 -RGD nanoprobe and the Fe 3 O 4 mother nanoparticles, respectively, are carefully compared. In addition, an RGD blocking experiment is also carried out to support the excellent binding specificity of the Fe 3 O 4 -RGD nanoprobe. Following the above experiments, cerebral ischemia-reperfusion studies show the collateral dynamics upon reperfusion, which is very important for the prognosis of various revascularization therapies in the clinic. The current study has, for the first time, enabled the direct observation of collaterals in a quasi-real time fashion and further disclosed that the antegrade flow upon reperfusion dominates the blood supply of primary ischemic tissue during the early stage of infarction, which is significantly meaningful for clinical treatment of stroke., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Single-chain technology (SCT) allows the manipulation of polymeric architectures at an individual polymer chain level, providing a new platform for the fabrication of nanoscale polymeric objects. However, it remains problematic to apply this newborn technology to the biological and medical fields, since synthesis of single-chain polymeric nanoparticles relies heavily on controlled/living radical polymerization of vinyl based monomers, yielding a persistent non-degradable carbon-carbon based backbone. Moreover, the ultrahigh dilution conditions often required for single-chain polymer nanoparticle synthesis limits large-scale applicability. A versatile approach to achieve backbone degradability in single-chain cyclized polymers was developed by combining ring-opening addition polymerization and intramolecular cyclization into a one-pot RAFT copolymerization of cyclic and mono/multi-vinyl monomers system under concentrated conditions. The in situ intramolecular cyclization of individual propagating chains was achieved by kinetic control and statistical manipulation of mono- and multi-vinyl monomer copolymerization. The cyclic allylsulfide monomer 3-methylidene-1,9-dioxa-5,12,13-trithiacyclopentadecane-2,8-dione (MDTD) was copolymerized via the ring-opening pathway to introduce disulfide groups into the vinyl-based backbone without compromising the single chain propagation nature. Backbone degradable single chain polymeric nanoparticles were obtained with molecular weights of 10kDa and MDTD incorporation ratios of 4.7%. Chemical degradation of the nanoparticles confirmed both their single chain nature, as well as backbone degradability. The single-chain cyclized polymeric nanoparticles were evaluated for their gene transfection capabilities. The backbone degradable nanoparticles displayed high transfection efficiencies and low cytotoxicities in both 3T3 and HeLa cells., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Overabundance of hydrogen peroxide originating from environmental stress and/or genetic mutation can lead to pathological conditions. Thus, the highly sensitive detection of H2 O2 is important. Herein, supramolecular fluorescent nanoparticles self-assembled from fluorescein isothiocyanate modified β-cyclodextrin (FITC-β-CD)/rhodamine B modified ferrocene (Fc-RB) amphiphile were prepared through host-guest interaction between FITC-β-CD host and Fc-RB guest for H2 O2 detection in cancer cells. The self-assembled nanoparticles based on a combination of multiple non-covalent interactions in aqueous medium showed high sensitivity to H2 O2 while maintaining stability under physiological condition. Owing to the fluorescence resonance energy transfer (FRET) effect, addition of H2 O2 led to obvious fluorescence change of nanoparticles from red (RB) to green (FITC) in fluorescent experiments. In vitro study showed the fluorescent nanoparticles could be efficiently internalized by cancer cells and then disrupted by endogenous H2 O2 , accompanying with FRET from "on" to "off". These supramolecular fluorescent nanoparticles constructed via multiple non-covalent interactions are expected to have potential applications in diagnosis and imaging of diseases caused by oxidative stresses., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Multifunctional and modular block copolymers prepared from biocompatible monomers and linked by a bioreducible disulfide linkage have been prepared using a combination of ring-opening and atom-transfer radical polymerizations (ATRP). The presence of terminal functionality via ATRP allowed cell-targeting folic acid groups to be attached in a controllable manner, while the block copolymer architecture enabled well-defined nanoparticles to be prepared by a water-oil-water double emulsion procedure to encapsulate DNA with high efficiency. Gene delivery assays in a Calu-3 cell line indicated specific folate-receptor-mediated uptake of the nanoparticles, and triggered release of the DNA payload via cleavage of the disulfide link resulted in enhanced transgene expression compared to nonbioreducible analogues. These materials offer a promising and generic means to deliver a wide variety of therapeutic payloads to cells in a selective and tunable way.

Chemodynamic therapy (CDT) is a highly effective clinical treatment strategy based on the Fenton or Fenton‐like responses. However, its efficacy has been greatly limited by the complex tumor microenvironment, TME, such as the low levels of H2O2 and the overexpression of the glutathione (GSH). Polyoxometalates (POMs) are compounds that consist of anionic transition metal oxide clusters, such as tungsten (W) and molybdenum (Mo), and notably, these compounds have excellent redox properties in biological systems that can be utilized therapeutically. Therefore, POM‐CaO2@ZIF‐8 nanoparticles (NPs) have been synthesized and used as a mediator to develop an electrically enhanced CDT strategy. It is hoped that the simultaneous modulation of endogenous (the H2O2 generated by CaO2 NPs and GSH depletion by POM) and exogenous (Electric, E) stimulation enhanced Fenton‐like responses will lead to better therapeutic results. Such a treatment strategy has shown excellent tumor cell killing effects in both in vitro and in vivo studies. [ABSTRACT FROM AUTHOR]

Propylene epoxidation by oxygen over Cu-based catalysts is a most ideal and economical process. The unsupported CuOx nanoparticles were synthesized by liquid phase reduction method. The crystalline phase and size of CuOx nanoparticles were characterized by XRD and TEM, respectively. The catalytic performances of CuOx with different pretreatment temperatures and atmospheres were also investigated. The as prepared unsupported CuOx nanoparticles were composed of Cu and Cu2O. With elevating the pretreatment temperatures under N2 atmosphere, the size of CuOx nanoparticles increased gradually from 25 nm to 58 nm. However, the relative content between Cu and Cu2O remained almost unchanged, indicating that the valence state of Cu species in CuOx was kept nearly constant. The C3H6 epoxidation activities showed a first increases and then decreases trend with enhancing the particle size of CuOx. The highest activity of propylene epoxidation was achieved when the particle size of CuOx was 41 nm. The conversion of propylene was 0.14% and the selectivity of propylene oxide was 30% respectively under the reaction temperature of 150 °C. The results indicated that the appropriate CuOx particle size was a key factor for propylene oxide formation on Cu-based catalysts. The C3H6 epoxidation activities showed a first increases and then decreases trend with enhancing the particle size of CuOx. When the CuOx particle size was 41 nm, the formation rate of PO reached maximum. The appropriate particle size of Cu species with low valence state was crucial to the generation of PO for C3H6 epoxidation reaction by O2 on Cu-based catalysts. [ABSTRACT FROM AUTHOR]

Overabundance of hydrogen peroxide originating from environmental stress and/or genetic mutation can lead to pathological conditions. Thus, the highly sensitive detection of H2O2 is important. Herein, supramolecular fluorescent nanoparticles self-assembled from fluorescein isothiocyanate modified β-cyclodextrin (FITC-β-CD)/rhodamine B modified ferrocene (Fc-RB) amphiphile were prepared through host-guest interaction between FITC-β-CD host and Fc-RB guest for H2O2 detection in cancer cells. The self-assembled nanoparticles based on a combination of multiple non-covalent interactions in aqueous medium showed high sensitivity to H2O2 while maintaining stability under physiological condition. Owing to the fluorescence resonance energy transfer (FRET) effect, addition of H2O2 led to obvious fluorescence change of nanoparticles from red (RB) to green (FITC) in fluorescent experiments. In vitro study showed the fluorescent nanoparticles could be efficiently internalized by cancer cells and then disrupted by endogenous H2O2, accompanying with FRET from 'on' to 'off'. These supramolecular fluorescent nanoparticles constructed via multiple non-covalent interactions are expected to have potential applications in diagnosis and imaging of diseases caused by oxidative stresses. [ABSTRACT FROM AUTHOR]

A fabrication process that combines an ultrathin alumina membrane (UTAM) surface nanopatterning technique and a physical vapor deposition method has been designed for realizing well-defined Au nanoparticle arrays for sensitive, uniform, and stable surface-enhanced Raman scattering (SERS)-active substrates. High Raman signals are obtained by adjusting the structural parameters of the metallic nanoparticles when rhodamine 6G (R6G) and 4-mercaptopyridine (4-MP) are used as the probe molecules. The corresponding estimated enhancement factors (EFs) are 6.5×106 (R6G) and 6.8×105 (4-MP), respectively. The simulated distributions of the electric field of SERS substrates coincide with the experimental results. Raman measurements at randomly selected spots on a substrate show a standard EF deviation of about 5 %, which indicates a desirable SERS uniformity. An advantageous feature of our SERS substrate is its long-term stability of enhanced Raman signals. Raman measurements on a substrate after one year show almost the same magnitude of Raman signal (106 for R6G and 105 for 4-MP) as that of the original measurement. Such substrates with good SERS sensitivity, uniformity, and stability should have high potential for SERS-related applications. [ABSTRACT FROM AUTHOR]

• SnO 2 /MoS 2 nanocomposite ammonia sensor was prepared by hydrothermal synthesis. • SnO 2 /MoS 2 had a flower-like structure with SnO 2 nanocrystals decorated on MoS 2 nanosheets. • SnO 2 /MoS 2 exhibited remarkable sensitivity much higher than that of pure MoS 2. • SnO 2 /MoS 2 showed rapid response and recovery times and excellent selectivity. • SnO 2 /MoS 2 sensors have potential applications in the NH 3 gas-sensing field. In this work, MoS 2 nanosheets decorated with SnO 2 nanoparticles were prepared via a facile two-step hydrothermal method, which possesses a proposed sensing composite structure of supporting layer/sensitive dots. The SnO 2 /MoS 2 nanocomposites exhibited an excellent sensing response (2080.36) toward 200 ppm NH 3 , which was ∼27.5 times higher than that of pristine MoS 2 films, a fast response/recovery time (23/1.6 s) toward 50 ppm at room temperature (22℃), and outstanding selectivity to NH 3 against CH 4 , H 2 , CO, H 2 S, and NO 2 and good repeatability. The excellent gas sensing properties could be dominated by the unique thin layers assembled flower-like structures of 2D MoS 2 , which foster the carrier charge transfer process and the reaction to SnO 2 /MoS 2 and NH 3. These results present the SnO 2 /MoS 2 nanocomposites promising candidate materials for high-performance NH 3 gas sensing at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: Rare-earth ions (Eu3+, Tb3+, Dy3+) doped SrMoO4 nanoparticles were prepared by solvothermal route using oleic acid as surfactant to control the particle shape and size. X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), photoluminescence spectra (PL) and the kinetic decay times were applied to characterize the obtained samples. The XRD patterns reveal that all the doped samples are assigned to the scheelite-type tetragonal structure of SrMoO4 phase. In addition, the as-synthesized SrMoO4:Ln (Ln=Eu3+, Tb3+, Dy3+) particles are high purity well crystallized and with the average size of 30–50nm. The possible formation process of SrMoO4:Ln (Ln=Eu3+, Tb3+, Dy3+) nanoparticles have been discussed as well. Upon excitation by ultraviolet radiation, the as-synthesized SrMoO4:Ln (Ln=Eu3+, Tb3+, Dy3+) nanoparticles exhibit the characteristic emission lines of corresponding Eu3+, Tb3+, Dy3+, respectively. [Copyright &y& Elsevier]

Abstract: A novel strategy to synthesize hybrid metal–polymer nanocomposites has been achieved based on in situ free radical suspension and bulk polymerization techniques. An organometallic precursor complex is dissolved in a liquid monomer phase prior to polymerization, where upon the precursor molecules are immobilized inside the polymer matrix during its formation. In a separate step, metal nanoparticles are then formed by H2-assisted reduction of the precursor in the polymer product in supercritical carbon dioxide (scCO2). The synthesized nanocomposites were characterized by GPC, TGA, SEM and TEM. It is shown that the metal nanoparticles are uniformly distributed inside the polymer matrix and the inclusion of the metal precursor has no significant influence on the polymerization process. The current work represents a simple and universal way to prepare a variety of metal–polymer nanocomposite functional materials. [Copyright &y& Elsevier]

Abstract: Stable aqueous dispersions of silver nanoparticles have been synthesized from an organometallic precursor dissolved in an organic phase. Hydrogen gas is used to reduce the precursor to form silver nanoparticles which spontaneously transfer into an immiscible aqueous phase where they are stabilized. This route provides a simple pathway for the preparation of aqueous nanoparticle solutions and avoids production of the inorganic ions that are usually associated with aqueous methods. The effectiveness of a variety of aqueous stabilizing agents is evaluated. All products show plasmon absorption bands characteristic of silver nanoparticles and transmission electron microscopy reveals most particles to be below 40 nm in diameter. [Copyright &y& Elsevier]

Abstract: Eu3+, Dy3+ and Sm3+ doped nano-sized YP0.8V0.2O4 phosphors were synthesized by a simple and facile microwave assisted hydrothermal process. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) spectra as well as kinetic decay were used to characterize the samples. Under ultraviolet excitation, the YP0.8V0.2O4:Ln3+ showed the VO4 3− self-emission band at approximately 452nm and the characteristic emission of doped lanthanide ions (Ln3+). The VO4 3− self-emission band decreases when the concentration of lanthanide ion increases, because lanthanide ions acts as activator and receives an efficient energy transfer from VO4 3−. Through changing the kinds and concentrations of doped Ln3+, the emission colors of the nanophosphor can be tuned in a wide region on CIE color coordinates, making the material have potential application in biolabels. [Copyright &y& Elsevier]