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A series of hollow carbon nanospheres embedded with MRI agents γ-Fe2O3 and GdPO4 nanoparticles (Fe–Gd/HCS), were prepared and applied to in vitro/vivo evaluation with well defined sizes of ∼100 nm, ∼200 nm, ∼300 nm, respectively.

Nitric oxide is critical for eliminating infection and promoting regeneration in diabetic wounds. However, clinical uses of nitric oxide are limited by its high activity and lack of specificity in targeting infections. Herein, we develop an intelligent nitric oxide nanogenerator comprising isosorbide dinitrate (ISDN)-coated copper sulfide (CuS)/calcium carbonate (CaCO

Improvement of the low-cost transition metal electrocatalyst used in sluggish oxygen evolution reaction is a significant but challenging problem. In this study, ultrafine Fe-modulated Ni nanoparticles embedded in a porous Ni-doped carbon matrix were produced by the pyrolysis of zirconium metal-organic-frameworks, in which 2,2′-bipyridine-5,5′-dicarboxylate operating as a ligand can coordinate with Ni2+ and Fe3+. This strategy allows formation of Fe-modulated Ni nanoparticles with a uniform dimension of about 2 nm which can be ascribed to the spatial blocking effect of ZrO2. This unique catalyst displays an efficient oxygen evolution reaction electro-catalytic activity with a low overpotential of 372 mV at 10 mA·cm−2 and a small Tafel slope of 84.4 mV·dec−1 in alkaline media. More importantly, it shows superior durability and structural stability after 43 h in a chronoamperometry test. Meanwhile, it shows excellent cycling stability during 4000 cyclic voltammetry cycles. This research offers a new insight into the construction of uniform nanoscale transition metals and their alloys as highly efficient and durable electrocatalysts.

Nano-immunotherapy has been recognized as a highly promising strategy for cancer treatment in recent decades, which combines nanotechnology and immunotherapy to combat against tumors. Hybrid nanomaterials consisting of at least two constituents with distinct compositions and properties, usually organic and inorganic, have been engineered with integrated functions and enormous potential in boosting cancer immunotherapy. This review provides a summary of hybrid nanomaterials reported for cancer immunotherapy, including nanoscale metal-organic frameworks, metal-phenolic networks, mesoporous organosilica nanoparticles, metallofullerene nanomaterials, polymer-lipid, and biomacromolecule-based hybrid nanomaterials. The combination of immunotherapy with chemotherapy, chemodynamic therapy, radiotherapy, radiodynamic therapy, photothermal therapy, photodynamic therapy, and sonodynamic therapy based on hybrid nanomaterials is also discussed. Finally, the current challenges and the prospects for designing hybrid nanomaterials and their application in cancer immunotherapy are outlined.

Immunomodulation has made remarkable progress in fighting infectious disease and cancer. Conventionally, immunomodulation largely relies on chemical/biochemical agents, which, unfortunately, suffer from sever off-target adverse effects. Recent insights into nano-bio interactions suggest that nanomaterials can directly participate in immunomodulation. A range of physical and chemical cues at the nano-bio interface have been harnessed to regulate diverse immuno-signaling for disease control and treatment. In this Minireview, we summarize recent studies on the physical and chemical cues enabled by intrinsic nanomaterials to trigger immunological signaling. First, we discuss physical cues mediated by surface topography, hydrophobicity, charge, and heat at the nano-bio interface for immunomodulation. Then, various nanomaterials enabled chemical cues, such as metal species and oxidative species are outlined. Finally, our perspectives on challenges and possible future directions are provided.

The rapid, discriminative, and portable detection of highly toxic chemical warfare agents is extremely important for response to public security emergencies but remains a challenge. One plausible solution involves the integration of porous molecular traps onto a photoelectrochemical (PEC) sensor. Here, a fast and facile protocol is developed to fabricate sub-1 nm AgNPs encapsulated hydrogen-bonded organic framework (HOF) nanocomposite materials through an in situ photoreduction and subsequent encapsulation process. Compared to traditional semiconductors and selected metal-organic frameworks (MOF) materials, these AgNPs@HOFs show significantly enhanced photocurrent. Most importantly, the portable PEC device based on AgNPs@HOF-101 can selectively recognize 13 different mustard gas simulants, including 2-chloroethyl ethyl sulfide (CEES), based on synergistic size-exclusion and specific recognition. The extremely low detection limit for CEES (15.8 nmol L

Porous materials bearing stepwise-controlled pore-shape change that are capable of executing sophisticated tasks are of considerable interest due to their fascinating features. In this work, we present a (3,4,6)-connected metal–organic framework built of 1D hinge-like zig–zag chain and tritopic ligand, formulated as (H3O)2[Zn3(dmtrz)2(tipa)2]·4H2O (MAC-20, Hdmtrz = 3,5-dimethyl-1H-1,2,4-triazole, H3tipa = 5-(2H-tetrazol-5-yl)isophthalic acid). By regulating the hinge angle and hydrogen bond interaction of 1D chain and tritopic ligand precisely, we realize a unique two-step pore-shape change in MAC-20 structure, which reveals that 1D chain and tritopic ligands have a synergistic effect on the structural transformation. Furthermore, the MAC-20 structure executes the sequential adsorption of indigo blue (ID) and sudan-I (SD-I) stepwise-controlled by trimethylamine and N,N-dimethylformamide, which offers the potential to exploit the flexible MOFs for smart multi-step stimuli-responsive applications.

Integrating magnetic resonance (MR) and photoacoustic (PA) contrast agents into porous nanomaterials is a favorable way for screening of potential theranostic nanomedicines. Hollow carbon nanospheres (HCSs) dotted with GdPO4 and γ-Fe2O3 (Gd-Fe) nanoparticles are therefore prepared and studied in this work. The resultant Gd-Fe/HCSs possess a size of ∼100 nm with a cavity of ∼80 nm and a shell thickness of ∼10 nm, where the magnetic Gd-Fe nanoparticles are dotted. Owing to the synergistic effects, the Gd-Fe/HCSs give 2.5 times enhanced PA signals as compared with HCSs as well as the inherited MR imaging properties from Gd-Fe nanoparticles. In vivo MR and PA imaging of the liver in mice are consequently evaluated and validated. Furthermore, taking the tunable particle size, hollow cavity, shell thickness, and dotted amounts of nanoparticles into consideration, our studies here provide a useful structural model for the synergistic integration of MR and PA imaging in HCSs.

Tumor cells are rich in antigens, which provide a reliable antigen library for the design of personalized vaccines. However, an effective tumor vaccine vector that can efficiently deliver antigens to lymphoid organs to stimulate strong CD8+ cytotoxic T-lymphocyte immune response is still lacking. Here we designed a dual-antigen delivery system based on hepatitis B virus core antigen virus-like particles (HBc VLPs). We first confirmed that different antigen-loaded HBc VLP monomers could be assembled into nanoparticles (hybrid VLPs). Hybrid VLPs could slightly enhance bone marrow-derived dendritic cell maturation in vitro. Strikingly, hybrid VLPs could generate antigen-specific antitumor immunity and innate immunity in vivo which could significantly inhibit tumor growth or metastatic formation in a subcutaneous tumor or lung metastatic tumor model, respectively. Moreover, dual-epitope vaccination generated enhanced T-cell responses that potently inhibited tumor growth and metastatic formation. Together, this study provides a new powerful concept for cancer immunotherapy and suggests a novel design for VLP-based personalized nanomedicine.

Domain switching in ferroelectrics is at the heart of many functionalities, and the visualization of switching pathway is the key to understand the fundamental properties and to promote the applications of high-performance ferroelectrics. Here, we directly documented the multi-step domain switching in [110]-oriented 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (PMN-0.33 P T) single crystals under a cycling electric field with the help of in situ polarized light microscopy. Based on the characteristic domain configuration analysis, we demonstrated that the 180° switching process was consisted of multi-step 60° switching. Such a multi-step 60° switching pathway resulted in a large negative strain and an internal electric field, which contributes to a large polarization fatigue rate under the alternating electric field. Our works may provide a window to study the domain switching process and its effect on polarization fatigue in relaxor-ferroelectric single crystals.

The need for an accurate model that can derive the absorption coefficient of optical activity constituents from both marine water and coastal water remains necessary. This study aimed to develop an algorithm for determining the absorption coefficients for both phytoplankton and non-phytoplankton pigments [aph(λ) and adg(λ), respectively]. This algorithm included two portions: (1) the total absorption coefficients at the blue and green bands were computed using a neural network technology-based, quasi-analytical algorithm; and (2) the relationship between the adg(λ) coefficient and the coefficient of total absorption was analyzed. This algorithm was evaluated with both in-situ observations and remote-sensed satellite data. The results showed that the algorithm could produce acceptable results in the retrievals of adg(λ) and aph(λ) in both turbid and clear waters. The results also indicated that the proposed algorithm was effective for distinguishing between adg(λ) and aph(λ) from the total coefficients of absorption, even though more independent assessments using in-situ and remote-sensed data are required to further improve the approach.

As the largest consumer of coal energy, coal-fired power plants emit large amounts of PbCl2 each year, which is of wide concern due to its high toxicity, global migration, and accumulation. Unburned carbon is considered a promising adsorbent for effective PbCl2 removal. However, there is a problem that the current unburned carbon model cannot show the structure of carbon defects on the actual unburned carbon surface. Therefore, it is important to construct defective unburned carbon models with practical significance. In addition, the adsorption mechanism of PbCl2 by an unburned model is not studied deeply enough and the reaction mechanism is not clear yet. This has seriously affected the development of effective adsorbents. To reveal the adsorption mechanism of PbCl2 on unburned carbon, the adsorption mechanism of PbCl2 on defective unburned carbon surfaces was analyzed by using the density flooding theory to investigate the adsorption process of PbCl2 on different unburned carbon models. This will provide theoretical guidance for the design and development of adsorbents for the removal of PbCl2 from coal-fired power plants.

Advanced antibacterial methods are urgently needed to deal with possible infectious diseases. As promising alternatives to antibiotics, enzyme-mimic nanocatalysts face bottlenecks of low activities and indistinct catalytic mechanisms, which seriously restrict their development for anti-infection treatment. Herein, metastable copper sulfide (Cu2-xS) nanozymes with diversiform sizes and compositions were selected to adjust the electronic structure for enhancing enzyme-mimic activities. The as-synthesized large and thin nanoplates (L/TN nanoplates), with the stoichiometric ratio of Cu1.25S, were proven to possess the optimal peroxidase (POD)-mimic activity. Using quantum mechanics, it was theoretically revealed that the sulfur vacancies could alter the electronic structure of copper active sites and thus reduce the reaction energy barrier of H2O2 to·OH to promote the POD-mimic performance. Moreover, through enhanced enzyme-mimic activities, L/TN nanoplates achieved efficient depletion of glutathione and ascorbic acid for improving antibacterial performances. Further, synergizing with the NIR irradiation, the satisfactory destruction capability for bacteria and biofilm was achieved for L/TN nanoplates under an inflammatory level of hydrogen peroxide (50 μM). Altogether, this work provides a deeper understanding of geometrical and electronic properties-dependent antibacterial performance, and paves the way toward precise compositions and structures engineering of nanozymes.

IntroductionAbdominal surgery is associated with common complications, including decreased or poor appetite, abdominal distension, abdominal pain caused by decreased or absent gastrointestinal motility, anal arrest with flatus and defecation, and nausea and vomiting resulting from the use of anaesthetics and opioid analgesics. These complications seriously affect postoperative recovery, prolong hospital stay and aggravate patient burden. This study aims to investigate for the first time the efficacy of transcutaneous electrical acupoint stimulation (TEAS) combined with electroacupuncture (EA) therapy for rapid recovery after laparotomy for gastrointestinal surgery. There have been no clinical studies of this combination therapy.Methods and analysisThis will be a prospective, single-centre, three-arm, randomised controlled trial. A total of 480 patients undergoing abdominal surgery will be stratified according to surgery type (ie, gastric or colorectal procedure) and randomised into three groups; namely, the EA, TEAS +EA and control groups. The control group will receive enhanced recovery after surgery (ERAS)-standardised perioperative management, including preoperative education, optimising the anaesthesia scheme, avoiding intraoperative hypothermia, restrictive fluid infusion and reducing surgical trauma. The EA group will receive EA stimulation at LI4, PC6, ST36, ST37 and ST39 based on the ERAS-standardised perioperative management. Moreover, the TEAS +EA group will receive ERAS-standardised perioperative management; EA stimulation at the LI4, PC6, ST36, ST37 and ST39; and TEAS stimulation at ST21 and SP15. The primary outcome will be the GI-2 (composite outcome of time to first defaecation and time to tolerance of a solid diet). Secondary outcomes will include the time of first passage of flatus, time to first defaecation, time to tolerance of a solid diet, time to first ambulation, hospital duration from operation to discharge, pain and nausea vomiting scores on the Visual Analogue Scale, medication use, incidence of postoperative complications and evaluation of treatment modality acceptability. All statistical analyses will be performed based on the intention-to-treat principle.Ethics and disseminationEthics approval has been granted by the Ethics Committee on Biomedical Research, West China Hospital of Sichuan University (approval number: 2021; number 52). The results are expected to be published in peer-reviewed journals.Trial registration numberChiCTR2100045646.

Hierarchically ordered porous materials with tailored and inter-connected macro-, meso-, and micro-pores would facilitate the heterogeneous adsorption and catalysis processes for a wide range of applications but remain a challenge for synthetic chemists. Here, a general and efficient strategy for the synthesis of inverse opal metal-organic frameworks (IO MOFs) with a tunable size of macro-, meso-, and micro-pores is reported. The strategy is based on the step-wise template formation, precursor infiltration, solvo-thermal reaction, and chemical etching. As a proof of the general applicability of this strategy, a series of inverse opal zirconium-based MOFs with intrinsic micro- and/or meso-pores, including UiO-66, MOF-808, NU-1200, NU-1000 and PCN-777, and tunable macropores (1 µm, 2 µm, 3 µm, 5 µm, and 10 µm), have been prepared with outstanding yields. These IO MOFs demonstrate significantly enhanced absorption rates and faster initial hydrolysis rates for organophosphorus (OPs) aggregates compared to those of the pristine MOFs. This work paves the way for the further development of hierarchically ordered MOFs for advanced applications.

The size modulation of hollow carbon nanospheres (HCSs) has attracted great interest in the contexts of cellular uptake, drug delivery and bioimaging. In this study, a facile fabrication method was specifically used to minimize all influencing factors except for the particle size. A series of nanoparticles of hollow carbon nanospheres embedded with magnetic resonance imaging (MRI) nanoagent γ-Fe

In situ incorporating versatile magnetic iron nanoparticles into ordered mesoporous carbon (OMC) by means of synthetic methodology for functional integration is a great challenge. Inspired by the phenomenon of uniovular twins in nature, a homometallic [Fe9(μ3-O)4(O3PPh)3(O2CCMe3)13] ({Fe9P3}) cluster was synthesized and used as the ovulum to in situ produce dual-Fe nanoparticle (γ-Fe2O3 and Fe(PO3)3)-functionalized OMC (dual-Fe/OMC). In vitro magnetic resonance imaging (MRI) studies showed a longitudinal relaxation (r1) and transverse relaxation (r2) of 9.74 and 26.59 mM−1 s−1 with a r2/r1 ratio of 2.73 at 0.5 T. The MRI performances were further examined by mouse model with a subcutaneous HeLa tumor. In addition, the low cytotoxicity, considerable loading capacity and delivery of doxorubicin hydrochloride (DOX) were also studied in vitro. These results demonstrate the feasibility of the concept of uniovular twins in the one-pot preparation of dual-Fe/OMC for functional integration.

A series of isostructural lanthanide phosphonocarboxylate frameworks {(H3O)3[Ln7(pbpdc)6(DMF)4(H2O)3]·4H2O}n (named LnPCF, Ln = Tb, Eu and Gd, H4pbpdc = 4′-phosphono-[1,1′-biphenyl]-3,5-dicarboxylic acid) were solvothermally synthesized and characterized by the single crystal X-ray diffraction technique. By combining lanthanide cations with a phosphonocarboxylate ligand, a heptametallic lanthanide phosphonate [Ln7(PO3)6(COO)12] core was obtained. This core exhibited as a rare highly 18-connected node and was linked by the 3-connected pbpdc4− ligand, forming a (3,18)-connected framework with a novel topology of {43}6{438·676·839}. This LnPCF structure is an ideal platform for accommodating various lanthanide ions. The TbPCF and EuPCF show efficient luminescence emission due to the “antenna effect” and incorporating Gd3+ into the TbPCF results in a drastic luminescence enhancement. Fine colour tuning between green and red can be easily achieved in bimetallic TbxGd1−xPCFs. More significantly, upon combining a few percent of Nd3+ and Gd3+ with Tb3+, the resulting trimetallic Tb0.4Gd0.5Nd0.1PCF shows dual emissions of both visible and near-infrared light.

Nonhealing wounds have become a major healthcare burden worldwide. Chronic wound healing is universally hampered by the presence of bacterial infections that form biofilms. Therefore, in this study, a novel nanoliquid dressing based on a mild photothermal heating strategy was designed to provide safe healing of biofilm-infected wounds. Dilute nitric acid (HNO3) solution was employed to induce a redox process triggered by copper sulfide (CuS) nanoplates in the nanoliquid dressing. This redox process was further promoted by the mild photothermal effect (≤47.5 °C) that generated a sufficient amount of reactive oxygen species, resulting in less thermal injury to normal tissues. Correspondingly, with the safe concentration of CuS nanoplates (0.4 mg/mL), excellent bactericidal efficiencies up to 98.3 and 99.3% against ampicillin-resistant Escherichia coli (Ampr E. coli) and Staphylococcus aureus (S. aureus) were achieved, respectively. Moreover, the nanoliquid dressing exhibited a near-infrared enhanced destructive effect on mature biofilms. According to in vivo wound healing experiments in mice, the nanoliquid dressing increased the healing rate and reduced the inflammatory response. This study provides a novel insight into treating the biofilm-infected chronic wounds in the "post-antibiotic era".

Developing functional porous carbon is greatly desired for the capture of N-glycans from complex bio-samples. In this work, ferronickel graphene-based porous carbon composites (FeNi-G/PC-T, T = carbonization temperature) are facilely prepared and are characterized by the synergistic integration of magnetic separation, porosity and polar interaction. Studies of capture of N-linked glycans reveal that FeNi-G/PC-800 shows a remarkable performance to enrich N-linked glycans from standard bio-samples and real human serum, resulting in the successful profiling of 48 N-linked glycans in 5 μL human serum. Structure-property relationship studies further demonstrate that the synergistically integrated FeNi nanoparticles and graphene-based porous carbon in FeNi-G/PC-800 should play a key role in the capture performance.

We report a robust and rigid etb-type metal–organic framework, in which its pore surface is decorated with flexible ethoxyl groups. It shows unprecedentedly selective adsorption of acetone (ETN value of 0.355, kinetic diameter of 4.6 A) over methanol (ETN value of 0.762, kinetic diameter of 3.6 A) for their azeotropic mixture.

Developing feasible ways to achieve tunable gate-opening pressure (Pgo) while minimizing the side effects on the adsorption capacity and enthalpy is greatly desired for flexible MOFs. In this work, we focused on solving this issue by cobalt substitution. We showed the successful modulation of the energy required for the reversible transformation of a soft paddle-wheel so that the whole framework presented a substitution-dependent Pgo for CO2 adsorption.

There is great interest in integration of paramagnetic gadolinium compounds and superparamagnetic iron oxide-based nanoparticles into ordered mesoporous carbon spheres (OMCSs) as a combined platform for T

Urban Black and Odorous Water (BOW) has become an environmental problem in many cities in China. The use of satellite remote sensing technology to identify BOW is still in its infancy, and there are many problems that need further solutions. In order to monitor BOW by satellite, between 2016 and 2017, the reflectance of remote sensing and some other parameters of 173 samples were collected from multiple field water experiments first. The samples were located at the major BOW in the urban areas of four Chinese cities, and the differences in remote sensing reflectance of severe BOW (SBOW), moderate BOW (MBOW), and general water (GW) were analyzed. Based on field measurements of spectral data, six remote sensing classification or identification models of BOW were compared in terms of their correct identification rate and reliability. The results show that compared with the GW in the study area, the urban BOW has the lowest reflectance. The peaks and valleys were not obvious in the visible band, especially the remote sensing reflectance of heavy BOW, which fluctuated very little in the visible band. Compared with the other five models, the H Index model had the best identification correctness and reliability.