Metal–organic framework (MOF)–polymer mixed-matrix membranes (MMMs) have shown their superior performance in gas separation. However, their biological application has not been well-explored yet. ...Herein, a series of zirconium-based MOF MMMs with high MOF loading and homogeneous composition have been prepared through a facile drawdown coating process. Poly(ε-caprolactone) (PCL) has been selected as a binder for its good biocompatibility and biodegradability. Zr-MOF nanoparticles, UiO-66, and MOF-525, have been utilized as “filler” because of their superior chemical stability, good biological safety, and versatile functions. Both UiO-66/PCL MMMs and MOF-525/PCL MMMs have a uniform appearance even at the highest loading of 50 wt % for UiO-66 and 30 wt % for MOF-525, respectively. The integrity of pore structures of UiO-66 within MMMs maintains well, which is evidenced by dye separation. All obtained MMMs possess good biocompatibility and mechanical property. Upon irradiation, MOF-525/PCL MMMs generate reactive oxygen species and serve as effective antibacterial photodynamic agents against Escherichia coli. This study offers an alternative system for forming homogeneous MOF/polymer MMMs and represents the first example of exploiting hybrid MMMs for biological applications.
The development of a simple and straightforward strategy to synthesize multifunctional carbon dots for photodynamic therapy (PDT) has been an emerging focus. In this work, diketopyrrolopyrrole-based ...fluorescent carbon dots (DPP CDs) were designed and synthesized through a facile one-pot hydrothermal method by using diketopyrrolopyrrole (DPP) and chitosan (CTS) as raw materials. DPP CDs not only maintained the ability of DPP to generate singlet oxygen (1O2) but also have excellent hydrophilic properties and outstanding biocompatibility. In vitro and in vivo experiments demonstrated that DPP CDs greatly inhibited the growth of tumor cells under laser irradiation (540 nm). This study highlights the potential of the rational design of CDs for efficient cancer therapy.
The introduction of multiple components into one crystalline metal–organic framework (MOF) provides a feasible approach to fully understand the correlation of component heterogeneity and the whole ...performance. Herein, photoactive tetratopic chlorin (TCPC) ligands with different geometry and connectivity have been successfully incorporated into the Hf-UiO-66 archetype structure without altering the underlying topology by a facile strategy. Unlike previous porphyrin-nanoscale-MOFs (porphyrin-NMOFs) with homogeneous periodical porphyrin arrangements typically for photodynamic therapy (PDT) usage, we demonstrate that TCPC component heterogeneity within as-synthesized TCPC-UiO possesses both PDT and photothermal therapy (PTT) simultaneously, but PTT takes a more potent antitumor efficacy as proven in several photophysical characterizations and biological experiments in vitro. The high photothermal conversion efficiency, favorable photostability and biocompatibility, and strong X-ray attenuating ability of the Hf element within TCPC-UiO make it a potential platform for further application in multimodal CT/thermal/photoacoustic imaging. Additionally, TCPC-UiO shows an impressive anticancer activity against H22 tumor-bearing mice in vivo, and its tumor inhibition rate is above 90%. We anticipate that the current work may offer in-depth insight into the component heterogeneity and property relationship and also extend biological applications of NMOFs.
Covalent organic frameworks (COFs) have shown great potential in catalysis and the biomedical fields, but monodisperse COFs with tunable sizes are hard to obtain. Herein, we successfully developed a ...series of COFs based on electron donor–acceptor strategy in mild conditions. The synthetic COFs exhibit excellent colloidal stability with uniform spherical morphology. The sizes can be flexibly adjusted by the amount of catalyst, and the absorption spectra also vary with the sizes. By changing the electron-donating ability of the monomers, the corresponding COFs possess a wide range of absorption spectra, which can be even extended to the second near-infrared biowindow. The obtained COFs possess potent photothermal activity under laser irradiation, and could inhibit the growth of tumors effectively. This work provides a strategy for the synthesis of monodisperse COFs with variable absorption for their potential applications.
Porphyrin-based porous organic polymers are highly potential candidates for cancer theranostics. However, un-controllable particle size and unclear photoactive mechanisms have been deemed to be ...“Achilles’ heels” for their biomedical application. Herein, a facile self-template strategy has been applied to integrate two types of porous materials to build the MOF@POP-PEG nanocomposite (named HUC-PEG). As-synthesized HUC-PEG exhibited controllable particle shape and size, good biocompatibility, and better colloidal stability. Importantly, synergy “0 + 1 > 1” interface effects have been demonstrated to simultaneously enhance both the generation of more singlet oxygen (1O2) for photodynamic therapy (PDT) and local hyperthermia for photothermal therapy (PTT), thus to achieve favorable proliferation inhibition of tumor cell both in vitro and in vivo. Moreover, the strong X-ray attenuating ability of Hf element and excellent photothermal conversion efficacy endow this nanocomposite with computed tomography (CT)/photothermal imaging functions. We believe that our ingenious design may open a new horizon for the preparation of nanoscale POP-based therapeutic agents and also realize a paradigm shift in the understanding of photoactive mechanism in porous materials.
Nanoparticle assembled from organic molecules is a versatile platform to integrate various functionalities for theranostics. In this work, nanoparticles are constructed from chlorin dimers that are ...synthesized by reducing porphyrin molecules. Chlorin dimers can assemble into nanoscale aggregates in the absence of surfactants or other auxiliary agent. The resulting nanoparticles of chlorin dimer exhibit much higher absorbance than the porphyrin counterparts, resulting in enhanced photodynamic and photothermal activity upon irradiation. The forming nanoparticles can be effectively endocytosed by the tumor cells, inducing apoptosis under irradiation. Tumor growth on mice model is inhibited by the photodynamic and photothermal treatment in vivo. Furthermore, this nanoparticle can be used for photoacoustic imaging. It is believed that the integrated imaging and phototherapeutic capability in one nanoparticle is beneficial for future cancer diagnosis, therapy, and molecular imaging.
Robust organic nanoparticles are developed for simultaneous photodynamic and photothermal therapy as well as photoacoustic imaging. The formed nanoparticles possess enhanced absorbance, which results in better efficacy of phototherapy in tumor inhibition. This result can eventually be very helpful in design of simple and ideal nanoparticle formulations for cancer patients.
Cancer immunotherapy has witnessed significant advances in the past decade, however challenges associated with immune‐related adverse effects and immunosuppressive tumor microenvironment, have ...hindered their clinical application. Stimuli‐activatable nanomedicines hold great potential for improving the efficiency of cancer immunotherapy and minimizing the side effects via tumor‐specific accumulation, controllable drug release profile, and combinational therapy by integrating multiple therapeutic regimens. In this review, the recent advances of stimuli‐activatable nanomedicines for cancer immunotherapy are first described, with particular focus on endogenous stimuli including pH, glutathione, reactive oxygen species, and excessive enzymes within the tumor microenvironment. Then, the endogenous stimuli‐activatable nanomedicines that target tumor cells, immune cells, or periphery immune systems for eliciting sustained systemic immune activation and modulating the immunosuppressive tumor microenvironment, are described. Next, the general mechanisms underlying nanomedicine‐based immunotherapy by eliciting anti‐tumor immune responses and overcoming immunologic tolerance are described. Further, the emerging application of bioimaging techniques for monitoring immune response and evaluating therapy performance is described. Finally, the authors’ perspectives are provided for the clinical translation of nanomedicine‐based cancer immunotherapy.
The tumor microenvironment is different from normal tissues, due to factors such as tumor acidity, overproduced GSH/ROS, and excessive enzyme secretion. These endogenous stimuli can serve as triggers for the controllable release of the immunological agents. Thus, stimuli‐activatable nanomedicine can selectively interact with tumor cells, immune cells, or peripheral immune systems, which can offer innovative approaches for activating systematic antitumor immunity.
Smart responsive nanomaterials, which are sensitive to biological signals, are promising therapeutic formulations. It has been well studied that redox potential is much different at both tissue and ...cellular level. In this work, three organic nanoparticles with variable redox sensitivity were fabricated, and their redox sensitivity was evaluated and compared in detail. First, diselenide, disulfide, and carbon–carbon bond containing porphyrin dimers TPP-SeSe/TPP-SS/TPP-CC were synthesized. Then, the corresponding self-assembled nanoparticles (TPP-SeSe/TPP-SS/TPP-CC NPs) were prepared via nanoprecipitation method. As-synthesized nanoparticles were utilized to systematically compare the stimuli responsiveness to reductive agents (e.g., glutathione) in different conditions, especially in the living cells, through the singlet oxygen generation ability and the cytotoxicity. A series of experimental results demonstrated that the diselenide bond shows better superiority in reduction sensitivity than that of the disulfide or carbon–carbon bond, which contributed to faster delivery of the photosensitizer and facilitated exertion of better PDT activity. These results highlight the potential of the diselenide bond to be developed as a novel and effective platform to fabricate more functional stimuli-responsive nanomaterials.
To assess the risk of foodborne disease caused by Salmonella in broiler chickens from retail to table, and to find effective preventive measures according to the risk assessment results.
Using ...dose-response model and Combase database, to evaluate the chicken-Salmonella poisoning risk through the crosscontamination in the kitchen with @ RISK by combining monitoring data of broiler chickens in Heilongjiang Province and related data.
According to the results of the quantitative risk assessment, there was a high risk of chicken-Salmonella poisoning because of cross-contamination in the kitchen. Scenario analysis suggested that, if the raw chicken was frozen or refrigerated storage in retail, the average risk of chicken-Salmonella poisoning can be reduced 1/5.
The risk of Chinese residents suffering from chicken-Salmonella poisoning will be reduced effectively by using cold chain management of raw chicken in retail.
Porphyrin‐containing carbon dots (CDs) possess ultrasmall size, excellent water solubility, and photostability. These CDs can effectively generate cytotoxic singlet oxygen upon irradiation, and ...induce the cell apoptosis. Photodynamic ability of CDs inhibits the growth of hepatoma. This work not only sheds light on developing functional carbon dots, but also highlights the importance of special‐structure precursor molecules in synthesizing functional CDs.
