Jun Zhu

Tuning residual Zn content represented a promising strategy to overcome iron aggregation and metal leaching defects of MOF-derived Fe/NC persulfate activators. Herein, ZnFe/NC bimetallic catalysts with tunable Fe/Zn ratios were synthesized via reduction-passivation pyrolysis of Fe-ZIF-8. Regulating residual Zn via reduction time suppressed Fe sintering and optimized Fe⁰, Fe-N_x, and graphitic-N active sites. ZnFe/NC–4 (4 h reduction, Fe/Zn ratio = 3.08) exhibited the optimal persulfate activation performance, achieving complete rhodamine B (RhB) removal within 20 min and 71.61% mineralization under visible-light irradiation (300 W Xe lamp, 0.96 W/cm²). This was 1.21 and 1.87 times higher than that of the dark catalyst group and catalyst-free blank group, respectively. Meanwhile, only 6.37% cumulative Fe leaching was detected after three cycles, verifying that residual Zn effectively anchored Fe species within the carbon framework. The coupling effect of residual-Zn-tuned dual active sites and visible-light-assisted persulfate activation promoted charge separation and interfacial electron transfer, generating singlet oxygen (¹O₂) for RhB mineralization with reduced ecological risk. This present work provided a facile strategy to construct high-efficiency MOF-derived bimetallic activators for refractory organic wastewater treatment.

Driven by the progress of sustainable development, environmental remediation and water treatment have become increasingly important. Photocatalysis, capable of degrading pollutants through light (especially visible light) irradiation, has received widespread research attention. Titanium dioxide(TiO₂) is a promising photocatalyst, yet its practical use is limited by low visible-light utilization and rapid photogenerated charge recombination. Herein, an S-scheme TiO₂-WO₃(Tungsten trioxide) heterojunction was successfully fabricated; the difference in Fermi levels induces a built-in electric field directed from TiO₂ to WO₃, which thus constructs the S-scheme heterojunction. The as-prepared heterojunction exhibits a markedly enhanced transient photocurrent density, with the carrier lifetime prolonged from 2.69 ns to 41.61 ns. Under visible-light irradiation, the heterojunction achieves a methylene blue (MB) removal efficiency of over 95% within 90 min, and its pseudo-first-order kinetic rate constant k reaches 0.032 min⁻¹, which is approximately 16 times that of pure TiO₂. Radical trapping experiments confirm that the dominant active species responsible for the catalytic process are photogenerated holes and the hydroxyl radicals derived therefrom.

Although zinc oxide nanoparticles (ZnO NPs) with distinct physicochemical properties have attracted great attention, the application of ZnO NPs is still limited due to their potential biotoxicity. In this work, ZnO-Polygonatum sibiricum (PS) NPs are synthesized to overcome this challenge. The ZnO NPs stably combine with PS according to microstructural observation, particle size distribution, zeta potential results and Fourier transform infrared spectroscopy analysis. The cytotoxicity of ZnO NPs is alleviated by combining them with PS as a consequence of the diminished generation of reactive oxygen species and reinforced superoxide dismutase activity. Furthermore, the respiratory index and histopathologic results of mice exposed to NPs manifest that the pulmonary dysfunction caused by ZnO NPs is avoided in the ZnO-PS NPs group. This study provides the foundations for the amelioration and universal utilization of ZnO NPs and emphasizes the potential of ZnO-PS NPs in biomedical applications.

The anticancer treatment is largely affected by the microenvironment of the tumors, which not only resists the tumors to the thermo/chemo-therapy, but also promotes their growth and invasion. In this work, the angiogenesis factor is balanced by combining with the breathing hyperoxygen, for regulating the tumor microenvironment and also for relieving hypoxia and high tissue interstitial pressure, which promote drug delivery to tumor tissues by increasing the in vivo perfusion and reversing the immunosuppressive tumor. In addition, the designed multifunctional nanoparticles have a great potential for applications to the tumor dual-mode imaging including magnetic resonance (MR) and photoacoustic (PA) imaging. This work proposes a promising strategy to enhance the thermo/chemo-therapy efficacy by remodeling the tumor microenvironment, which would provide an alternative to prolong the lifetime of tumor patients. Graphical Abstract

In recent years, with the widespread use of zinc oxide (ZnO) nanoparticles (NPs), more and more attentions are being given to its biological toxicity, the toxicity of ZnO NPs under different exposure methods is necessary to investigate. In this study, we prepared two ZnO dispersions with different particle sizes, namely small-size ZnO (S-ZnO) and Bigsize ZnO (B-ZnO), using polycarboxylic acid as dispersant. Mice were poisoned by intravenous injection and inhalation, respectively. The respiration coefficient, superoxide dismutase (SOD), Zn content in the organs of the mice were detected. It was discovered that ZnO NPs with smaller particle diameter can cause more serious toxicity in vivo after intravenous exposure and respiratory exposure. In addition, the mice showed symptoms of dyspnea after respiratory exposure and a massive number of fibroblasts were found in the alveolar structure of the lungs. In the intravenous injection group, the content of Zn in the liver and spleen of mice increased significantly, resulting in organ edema, and the organ coefficient of mice increased. Finally, the increase of GSH/GSSG indicated that cells were regulated under the antioxidant mechanism, which accelerated the removal of H₂O₂ from cells. In addition, the increase of GSH+GSSG content also indicated that ZnO NPs stimulated the creation of reactive oxygen species (ROS) in organs of experimental animals.

To estimate the effect of a steady-state magnetic field (SMF) with low magnetic intensity gradient on the apoptosis-promoting factors related to cancer cells, we systematically select SMF with 0.2T, 0.4T and 0.6T to study their effect on different ovarian cancer lines. An in vitro cell model system about two kinds of ovarian cancer lines is established, whose viability and intracellular factors are detected by CCK-8, confocal microscopy and flow cytometry method. The results demonstrate that the apoptosis rate of ovarian cancer cells is increased with the enhancement of SMF magnetic intensity. Furthermore, we detect an increasing ROS and intracellular Ca²⁺ levels in ovarian cancer cells, which can be caused by SMF. The results suggest that ROS and Ca²⁺ levels are the main reason for the significant apoptosis of ovarian cancer cell lines in SMF. Moreover, an in vivo experiment also reveals that SMF has a strong inhibitory effect on ovarian cancer. Therefore, the inhibitory strategy is an effective, which has a great potential in the treatment of drug-resistant ovarian cancer.

A new kind of coating consisting of zinc oxide (ZnO)/tetracalcium phosphate (TTCP)/gelatin (Gel) on the PET woven nets is prepared chemically by the method of atomic layer deposition (ALD) and hydrothermal method. The prepared materials are confirmed by XRD and SEM. XRD results show that ZnO and TTCP are well coated on the surface of PET woven nets and ALD-assisted ZnO leads to a surprising coating adhesion of about 8 MPa. Furthermore, SEM results indicate the diameter and morphology of ZnO, TTCP and Gel of PET woven nets. And the water contact angles of PET’s surface are decreased with ZnO, TTCP and Gel of PET woven nets. Moreover, the confocal imaging of NIH3T3 cells shows that the obtained product could promote the cells proliferation, which indicates that the good biocompatibility of the prepared PET/ZnO/TTCP/ Gel woven builds a foundation for their future application. The results aim to obtain an efficient method to modify PET for fabricating an ideal artificial implant meeting the clinical needs, and imply a positive effect in promoting the compatibility of PET for enhancing graft-bone healing after implantation.