Xiaomeng Guo

Environmental pollution is a pressing global issue, characterized by diverse contaminants and the unsustainability of traditional treatment methods. Biodegradation offers an effective strategy to address this challenge, targeting pollutants such as antibiotics, pharmaceuticals, pesticides, dyes, polycyclic aromatic hydrocarbons, petroleum-derived compounds, plastics, persistent polymers, gaseous substances and so on. This review systematically summarizes recent advances in the use of microorganisms and enzymes for pollutant removal or transformation. Studies on microorganisms and enzymes capable of degrading different pollutant classes are presented, along with their degradation mechanisms and practical feasibility, providing guidance for researchers and industry practitioners and highlighting candidates with higher degradation potential. Furthermore, emerging approaches, including enzyme evolution and gene editing, synergistic strategies, immobilization technologies, and machine-learning-assisted optimization, are discussed as ways to enhance biodegradation stability and efficiency. Notably, directed evolution has achieved up to 400-fold enhancement in catalytic efficiency, while machine-learning models have reached high classification accuracy (AUC = 0.99) in predicting pollutant degradation.

The Fe-N ₄ /Te-CN catalyst achieves 2.31-fold higher activity than its non-polar Fe-N ₄ /CN counterpart, underscoring the role of induced polarity as a pivotal lever for NRA performance.

ZnCdS quantum dots (QDs) are highly coveted in photocatalysis research for their exceptional visible-light responses and high light-absorption coefficients. However, their practical application is hindered by their tendency to aggregate, due to having high surface energies. To address this issue, herein, a heterostructure is synthesized by growing ZnCdS QDs with a size of approximately 5 nm onto the surface of a two-dimensional (2D) covalent organic framework (COF), TpPa-1-COF. This approach suppresses the aggregation of the QDs and improves their stability. The ZnCdS/TpPa-1-COF composite exhibited a peak hydrogen evolution rate of 6244.16 µmol·g⁻¹·h⁻¹, which was 2.89 and 4.18 times greater than that of ZnCdS and TpPa-1-COF, respectively. The zero-dimensional/two-dimensional (0D/2D) heterojunction formed by ZnCdS and TpPa-1-COF generates a strong interfacial force, which is attributed to the intimate contact between the interfaces. Tight connections accelerate charge separation, improve the utilisation of reduced electrons, and reduce the extent of agglomeration of the ZnCdS QDs, thereby resulting in high hydrogen production activity of the composites. Meanwhile, the photocatalytic mechanism is studied using Kelvin probe force microscopy and theoretical calculations. This study offers a novel approach for creating sulfide photocatalysts and is crucial for investigating the potential practical applications of the related photocatalysts.

Local hypoxia in solid malignancies often results in resistance to radiotherapy (RT) and chemotherapy (CT), which may be one of main reasons for their failure in clinical application. Especially oxygen is an essential element for enhancing DNA damage caused by ionizing radiation in radiotherapy. Here, two biomimetic oxygen delivery systems were designed by encapsulating hemoglobin (Hb) alone into a liposome (Hb-Lipo) or co-encapsulating Hb and doxorubicin (DOX) into a liposome (DOX-Hb-Lipo). Our data indicated that both Hb-Lipo and DOX-Hb-Lipo could effectively alleviate the hypoxia in tumors. We demonstrated that RT plus tumor-targeting delivery of oxygen mediated by Hb-Lipo could significantly overcome the tolerance of hypoxic cancer cells to RT, showing significantly enhanced cancer cells killing and tumor growth inhibition ability, mainly attributing to hypoxia alleviation and increased ROS production under RT in cancer cells. Furthermore, a melanoma model that was quite insensitive to both RT and CT was used to test the efficacy of chemo-radiotherapy combined with hypoxia alleviation. RT plus Hb-Lipo only caused a limited increase in antitumor activity. However, extremely strong tumor inhibition could be obtained by RT combined with DOX-Hb-Lipo-mediated CT, attributing to radio-triggered DOX release and an enhanced immunogenic cell death induced by RT under oxygen supplement. Our study provided a valuable reference for overcoming hypoxia-induced radioresistance and a useful therapeutic strategy for cancers that are extremely insensitive to chemo- or radiotherapy.