Precise design of dual active-site catalysts for synergistic catalytic therapy of tumors.

A proven and promising method to improve the catalytic performance of single-atom catalysts through the interaction between bimetallic atoms to change the active surface sites or adjust the catalytic sites of reactants is reported. In this work, we used an iron-platinum bimetallic reagent as the metal source to precisely synthesise covalent organic framework-derived diatomic catalysts (FePt-DAC/NC). Benefiting from the coordination between the two metal atoms, the presence of Pt single atoms can successfully regulate Fe-N3 activity. FePt-DAC/NC exhibited a stronger ability to catalyze H2O2 to produce toxic hydroxyl radicals than Fe single-atom catalysts (Fe-SA/NC) to achieve chemodynamic therapy of tumors (the catalytic efficiency improved by 186.4%). At the same time, under the irradiation of an 808 nm laser, FePt-DAC/NC exhibited efficient photothermal conversion efficiency to achieve photothermal therapy of tumors. Both in vitro and in vivo results indicate that FePt-DAC/NC can efficiently suppress tumor cell growth by a synergistic therapeutic effect with photothermally augmented nanocatalytic therapy. This novel bimetallic dual active-site monodisperse catalyst provides an important example for the application of single-atom catalysts in the biomedical field, highlighting its promising clinical potential.

A dual gate-controlled intelligent nanoreactor enables collaborative precise treatment for cancer nanotherapy.

Recently, disulfiram (DSF), approved by the FDA as an anti-alcoholic drug, has been proved as an effective antitumor drug after chelating with Cu2+. To overcome the shortage of intracellular Cu2+, we have constructed a dual gate-controlled intelligent nanoreactor (HA-DSF@HCuS@FePtMn, HDHF) via the ingenious combination of hollow copper sulfide (HCuS) nanoparticles, DSF and FePtMn nanocrystals. HDHF has a NIR-actuated gate and enzyme-actuated gate that could be opened in the hyaluronidase-abundant tumor microenvironment with NIR laser irradiation to trigger drug (DSF/FePtMn) release and synergistic therapy. Moreover, the FePtMn nanocrystals could continuously release Fe2+, which could catalyze H2O2 into highly cytotoxic hydroxyl radicals (˙OH), triggering chemodynamic therapy (CDT). When exposed to NIR laser, HCuS could collapse and release Cu2+, which could immediately chelate with DSF, forming the effective anticancer drug (Cu(DTC)2) and enabling DSF-based chemotherapy. More importantly, the efficient photothermal therapy (PTT) effect of HCuS could accelerate the FePtMn-based CDT and the release of Cu2+/DSF, improving tumor treatment efficiency. Thus, this study represents a distinctive paradigm of a dual gate-controlled intelligent nanoreactor enabled PTT-augmented DSF-based chemotherapy and FePtMn-based CDT for cancer nanotherapy.

Oncocyte Membrane-Camouflaged Multi-Stimuli-Responsive Nanohybrids for Synergistic Amplification of Tumor Oxidative Stresses and Photothermal Enhanced Cancer Therapy.

The combination of various therapeutic modalities has received considerable attention for improving antitumor performance. Herein, an innovative nanohybrid, namely CaO2@FePt-DOX@PDA@CM (CFDPM), was developed for synergistic chemotherapy/chemodynamic therapy/Ca2+ overloading-mediated amplification of tumor oxidative stress and photothermal enhanced cancer therapy. Camouflage of the 4T1 cell membrane enabled CFDPM to escape the immune surveillance and accumulate in the tumor tissue. Ca2+, released from CaO2, could lead to mitochondrial dysfunction and facilitate the production of reactive oxygen species to amplify intracellular oxidative stress. Meanwhile, the increase of H2O2 concentration could enhance the efficiency of the chemodynamic therapy (CDT). Moreover, the hypoxic condition could be alleviated remarkably, which is attributed to the sufficient O2 supply by CaO2, resulting in the suppression of drug resistance and promotion of the chemotherapeutic effect. The nanohybrids involving Ca2+ overloading/CDT/chemotherapy could synergistically amplify the tumor oxidative stresses and remarkably aggravate the death of cancer cells. Significantly, the excellent photothermal conversion performance of CFDPM could further promote the tumoricidal effect. The in vitro and in vivo studies revealed that CFDPM could effectively advance the therapeutic efficiency via the cooperation of various therapeutic modalities to optimize their individual virtue, which would open a valuable avenue for effective cancer treatment.

Precise Design of Atomically Dispersed Fe, Pt Dinuclear Catalysts and Their Synergistic Application for Tumor Catalytic Therapy.

Recently, extending single-atom catalysts from mono- to binary sites has been proved to be a promising way to realize more efficient chemical catalytic processes. In this work, atomically dispersed Fe, Pt dinuclear catalysts ((Fe, Pt)SA-N-C) with an ca. 2.38 Šdistance for Fe1 (Fe-N3) and Pt1 (Pt-N4) could be precisely controlled via a novel secondary-doping strategy. In response to tumor microenvironments, the Fe-N3/Pt-N4 moieties exhibited synergistic catalytic performance for tumor catalytic therapy. Due to its beneficial microstructure and abundant active sites, the Fe-N3 moiety effectively initiated the intratumoral Fenton-like reaction to release a large amount of toxic hydroxyl radicals (•OH), which further induced tumor cell apoptosis. Meanwhile, the bonded Pt-N4 moiety could also enhance the Fenton-like activity of the Fe-N3 moiety up to 128.8% by modulating the 3d electronic orbitals of isolated Fe-N3 sites. In addition, the existence of amorphous carbon revealed high photothermal conversion efficiency when exposed to an 808 nm laser, which synergistically achieved an effective oncotherapy outcome. Therefore, the as-obtained (Fe, Pt)SA-N-C-FA-PEG has promising potential in the bio-nanomedicine field for inhibiting tumor cell growth in vitro and in vivo.

Advances in FePt-involved nano-system design and application for bioeffect and biosafety.

The rapid development and wide application of nanomaterial-involved theranostic agents have drawn surging attention for improving the living standard of humankind and healthcare conditions. In this review, recent developments in the design, synthesis, biocompatibility evaluation and potential nanomedicine applications of FePt-involved nano-systems are summarized, especially for cancer theranostic and biological molecule detection. The in vivo multi-model imaging capability is discussed in detail, including magnetic resonance imaging and computed tomography. Furthermore, we highlight the significant achievements of various FePt-involved nanotherapeutics for cancer treatment, such as drug delivery, chemodynamic therapy, photodynamic therapy, radiotherapy and immunotherapy. In addition, a series of FePt-involved nanocomposites are also applied for biological molecule detection, such as H2O2, glucose and naked-eye detection of cancer cells. Ultimately, we also summarize the challenges and prospects of FePt-involved nano-systems in nanocatalytic medicine. This review is expected to give a general pattern for the development of FePt-involved nano-systems in the field of nanocatalytic medicine and analytical determination.

Core-shell FePt-cube@covalent organic polymer nanocomposites: a multifunctional nanocatalytic agent for primary and metastatic tumor treatment.

Metastasis and spread are currently the main factors leading to high mortality of cancer, so developing a synergetic antitumor strategy with high specificity and hypotoxicity is in urgent demand. Based on the design concept of "nanocatalytic medicine", multifunctional nanotherapeutic agent FePt@COP-FA nanocomposites (FPCF NCs) are developed for cancer treatment. Specifically, in the tumor microenvironment (TME), FePt could catalyze intracellular over-expressed H2O2 to generate highly active hydroxyl radicals (˙OH), which could not only induce the apoptosis of tumor cells, but also activate the "ferroptosis" pathway resulting in the lipid peroxide accumulation and ferroptotic cell death. Moreover, owing to the excellent photothermal effect, the FPCF NCs could effectively ablate primary tumors under near-infrared (NIR) laser irradiation and produce numerous tumor-associated antigens in situ. With the assistance of a checkpoint blockade inhibitor, anti-CTLA4 antibody, the body's specific immune response would be initiated to inhibit the growth of metastatic tumors. In particular, such synergistic therapeutics could produce an effective immunological memory effect, which could prevent tumor metastasis and recurrence again. In summary, the FPCF NC is an effective multifunctional antitumor therapeutic agent for nanocatalytic/photothermal/checkpoint blockade combination therapy, which exhibits great potential in nanocatalytic anticancer therapeutic applications.

Preparation of mono-dispersed, high energy release, core/shell structure Al nanopowders and their application in HTPB propellant as combustion enhancers.

Mono-dispersed, spherical and core/shell structure aluminum nanopowders (ANPs) were produced massively by high energy ion beam evaporation (HEIBE). And the number weighted average particle size of the ANPs is 98.9 nm, with an alumina shell (3-5 nm). Benefiting from the passivation treatment, the friction, impact and electrostatic spark sensitivity of the ANPs are almost equivalent to those of aluminum micro powders. The result of TG-DSC indicates the active aluminum content of ANPs is 87.14%, the enthalpy release value is 20.37 kJ/g, the specific heat release S 1/Δm 1* (392-611 °C) which determined the ability of energy release is 19.95 kJ/g. And the value of S 1/Δm 1* is the highest compared with ANPs produced by other physical methods. Besides, the ANPs perfectly compatible with hydroxyl-terminated polybutadiene (HTPB), 3 wt. % of ANPs were used in HTPB propellant replaced micron aluminum powders, and improved the burning rate in the 3-12 MPa pressure range and reduced the pressure exponential by more than 31% in the 3-16 MPa pressure range. The production technology of ANPs with excellent properties will greatly promote the application of ANPs in the field of energetic materials such as propellant, explosive and pyrotechnics.

[Study on the Design of Explosive (HNS) Content Analysis System Based on THz Spectrum Monomer].

HNS quantitative spectral analysis can not be achieved with the existing infrared Fourier transform spectrometer. As a common monomer explosive concerned, quick identification and quantitative analysis of the substance is important, so it is necessary to research and design a HNS detection system based on THz spectroscopy. Transmissive mode was used in the system to calculate the content of HNS. Electro-optic modulator module was introduced in the system, in order to achieve steady and rapid static scanning optical path. In the experiments HNS characteristic absorption peak positions were acquired. With this basis, combined air absorption characteristics of the wavelength band and spectrum data correlation expression was obtained, thus more characteristic wavelengths selected were determined. According to Beer-Lambert law, the function expression of HNS content and coefficient formula were presented. In the experiment different content of HNS sample powder was obtained with chemical configuration method with the content at the standard level. It made HNS sample powder into HNS Sample slice for all HNS samples, and it carried out HNS content testing with MINI-Z Terahertz spectroscopy and the system. Experimental results show that the results of the two methods are similar in the range of 0.10% to 50.00% for HNS content. Their error is less than 5.0% compared to the standard value, and the system has better linearity.

[CNN]-pincer nickel(II) complexes of N-heterocyclic carbene (NHC): synthesis and catalysis of the Kumada reaction of unactivated C-Cl bonds.

Three novel [CNN]-pincer nickel(ii) complexes with NHC-amine arms were synthesized in three steps. Complex was proven to be an efficient catalyst for the Kumada coupling of aryl chlorides or aryl dichlorides under mild conditions.

Magnetically recoverable SiO2-coated Fe3O4 nanoparticles: a new platform for asymmetric transfer hydrogenation of aromatic ketones in aqueous medium.

A magnetically recoverable chiral rhodium catalyst exhibited excellent catalytic activity and enantioselectivity in asymmetric transfer hydrogenation of aromatic ketones in aqueous medium, which could be recovered easily via a small magnet and used repetitively ten times without obviously affecting its enantioselectivity.

[Research on improving sensitivity of the characteristic spectrum in micro-gas monitor].

In order to realize the indoor micro noxious gas real-time monitor, and enhance measuring accuracy based on the characteristic spectrum examination method, a characteristic wavelengths filtration window was designed, in which the container is full with the highly concentrated testing gas. The container with the highly concentrated testing gas was used as the filtration window, the standard air as the reference window, the air chamber sufficient testing gas for testing density. The experiment demonstrated that using the WQF-520-FTIR infrared spectroscope to obtain the infrared absorption spectrum of dipropyl sebacate, there were mainly four characteristic wavelength lines: 3.385 26, 3.417.64, 5.797 11, and 8.561 65 microm, and the corresponding extinction was 1.520 0, 1.542 1, 2.431 8 and 1.352 6 respectively. The smallest content examined was 50 ppb, but using the characteristic wavelengths filtration window, the method could realize the 10(-4) nm magnitude alignment. The sensitivity was enhanced nearly 10 times, and the characteristic wavelengths filtration window method has the merits of high sensitivity, no discontinuity, real-time examination, and so on.