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The serious environmental risks caused by Pb(II) and Sb(V) co-contamination increase the need for their efficient and simultaneous removal. In this study, the remediation feasibility by Fe-doped phosphogypsum (FPG) was elucidated for single systems with Pb or Sb pollutant and coexisting systems with both from water. As for single systems, Fe doping effectively enhanced the Pb(II) removal performance by phosphogypsum (PG) at low Pb(II) concentrations of below 100 mg/L via the combination of precipitation and complexation. The optimal removal rate of Sb(V) by FPG increased by 2.08-3.31 times as compared to that of by PG (10-120 mg/L), mainly due to the strong affinity of iron hydroxyl (≡Fe-O-H) towards Sb(V). Compared with the single systems, the coexistence greatly enhanced the Pb(II) and Sb(V) removal performance by FPG, and the interaction behavior between Pb(II) and Sb(V) on the FPG was concentration dependent. Briefly, the sorption of FPG controlled the elimination of low coexisting concentrations of Pb(II) and Sb(V), whereas the co-precipitation process between Pb(II) and Sb(V) predominated with high ions concentration. The significant synergistic effects were found during the removal of Pb(II) and Sb(V) on FPG in the coexisting system, which mainly attributed to precipitation, bridging complexation and electrostatic attraction. Considering the advantages such as facile preparation, low cost and high removal capacity, FPG is a promising material to uptake Pb(II) and/or Sb(V) from contaminated water.

PROteolysis TArgeting Chimeras (PROTACs) technology is a new protein-degradation strategy that has emerged in recent years. It uses bifunctional small molecules to induce the ubiquitination and degradation of target proteins through the ubiquitin–proteasome system. PROTACs can not only be used as potential clinical treatments for diseases such as cancer, immune disorders, viral infections, and neurodegenerative diseases, but also provide unique chemical knockdown tools for biological research in a catalytic, reversible, and rapid manner. In 2019, our group published a review article “PROTACs: great opportunities for academia and industry” in the journal, summarizing the representative compounds of PROTACs reported before the end of 2019. In the past 2 years, the entire field of protein degradation has experienced rapid development, including not only a large increase in the number of research papers on protein-degradation technology but also a rapid increase in the number of small-molecule degraders that have entered the clinical and will enter the clinical stage. In addition to PROTAC and molecular glue technology, other new degradation technologies are also developing rapidly. In this article, we mainly summarize and review the representative PROTACs of related targets published in 2020–2021 to present to researchers the exciting developments in the field of protein degradation. The problems that need to be solved in this field will also be briefly introduced.

The discovery of effective therapeutic treatments for cancer via cell differentiation instead of antiproliferation remains a great challenge. Cyclin-dependent kinase 2 (CDK2) inactivation, which overcomes the differentiation arrest of acute myeloid leukemia (AML) cells, may be a promising method for AML treatment. However, there is no available selective CDK2 inhibitor. More importantly, the inhibition of only the enzymatic function of CDK2 would be insufficient to promote notable AML differentiation. To further validate the role and druggability of CDK2 involved in AML differentiation, a suitable chemical tool is needed. Therefore, we developed first-in-class CDK2-targeted proteolysis-targeting chimeras (PROTACs), which promoted rapid and potent CDK2 degradation in different cell lines without comparable degradation of other targets, and induced remarkable differentiation of AML cell lines and primary patient cells. These data clearly demonstrated the practicality and importance of PROTACs as alternative tools for verifying CDK2 protein functions.

The rapid development of nanoparticles (NPs) and their broad applications in medicine caused concerns about biological effects and biosafety. Here, the interaction of silver NPs (Ag NPs) and trypsin is studied with ultravioletvisible spectra, circular dichroism, and fluorescence spectra. Trypsin is exposed to various sizes and concentrations of Ag NPs. The intensities of the trypsin ultraviolet-visible absorption peaks are proportional to the Ag NP concentration and size. In the circular dichroism spectra, there was evidence that Ag NPs affected the secondary structure of trypsin. Fluorescence spectra show that the formation of the protein-nanoparticle complexes alters the protein chromophore chemical environment or structure and quenches its fluorescence. Hence, the extent of Ag NP binding of trypsin depends on both NP concentration and size, and changes the Ag NPs physicochemical properties as well as the trypsin secondary structure. With regard to nanomaterial safety, the interaction of NPs with proteins must be explored further for establishing NP toxicity and design guidance.

In order to improve the mass transfer of anodic oxidation, an inverse opal-like marcoporous RuO2 electrode (IOMP-RuO2) was designed to enhance the concentration diffusion and molecule-to-electrode collision. Characterization methods including SEM, XRD, BET, LSV, CV, EIS and CA were performed to evaluate the properties of the IOMP-RuO2. In addition, the electro-oxidation capacity of the RuO2 electrode prepared at varying calcination temperature was also investigated. Results show that calcination temperature can affect the electro-oxidation performance of IOMP-RuO2 from the specific surface area, crystallinity of RuO2, voltammetric charge and impedance. Thereinto, crystallinity of RuO2 and impedance played decisive roles in the electrochemical oxidation. The fine crystallinity and lower impedance of IOMP-RuO2 acquired by 450 °C increased the electronic transport rate and allowed less redox couple to be involved in oxygen evolution, contributing to the best oxidation performance amongst others. Under this calcination temperature, the IOMP-RuO2 possesses larger electro-active areas, smaller electric resistance and enhanced mass transfer as compared to the planar RuO2 electrode. Furthermore, the IOMP-RuO2 gave a 42.7% higher degradation rate than that observed for the planar RuO2 electrode in the abatement of tricyclazole (TC) after 180 min. The high rate constant (2.14 × 10–2 min−1) and current efficiency (61.1%) achieved by IOMP-RuO2 contributed to a low energy consumption of 0.04744 kWh mg−1. Thus, these findings promoted the IOMP-RuO2 as an alternative electrode for wastewater decontamination.

The discovery and development of a novel HER-2 tyrosine kinase inhibitor for the treatment of HER2-positive breast cancer are presented in this article. EGFR family has been recognized as a crucial meditator in the cancer progression; HER-2 tyrosine kinase was one of the members among them. In the effort to explore potent HER-2 inhibitors, a novel series of 4-anilino-3-cyanoquinoline derivatives have been designed, synthesized and evaluated. Most compounds possessed modest proliferation inhibition on SK-BR-3 cell line and HER-2 kinase. Compound 16 appeared to be the most potent compound (HER-2 kinase IC50: 19.4 nM, SK-BR-3 IC50: 94 nM). In the experiment of cellular cytotoxicity assay, compound 16 shows a much lower cytotoxicity than neratinib on Beas-2b cell line (Human bronchial epithelial cells). In conclusion, compound 16 would be a promising lead compound for further anti-breast cancer drug discovery.

The important criteria in anaerobic digestion is the rate-limiting step which decides the fate of value-added products especially from waste-activated sludge (WAS). Hence, the present study investigated the effect of magnesium (Mg2+) addition on anaerobic digestion of WAS. The lab-scale experiments were conducted at 25 °C with Mg2+ doses ranging from 0.01 to 0.2 mol/L. Maximum total volatile fatty acids (VFAs) production (372.78 mg COD/L) occurred at a Mg2+ dose of 0.2 mol/L, which was about eight times higher than the control tests. Further, Mg2+ addition facilitated sludge dewaterability and phosphorus removal. The mechanism of improved VFAs generation was analyzed from the view of both chemical and biological effects. Chemical effect significantly enhanced the release of calcium and iron in WAS, resulting in the disintegration of WAS, which benefited hydrolysis and acidification processes. Illumina MiSeq sequencing analysis revealed that enrichment of functional bacteria and the increase of bacterial diversity were obtained in the 0.2 mol Mg2+/L experiment, while the influence was negative on the reactor with 0.025 mol/L Mg2+. Meanwhile, methanogens were accordantly inhibited in the experiments with Mg2+ addition.

For the treatment of high-strength pyridine containing wastewater, a bioaugmented continuous-flow self-forming dynamic membrane bioreactor (CSFDMBR), which was consisted of a continuous flow airlift reactor (CFAR) and a dynamic membrane bioreactor (DMBR), was developed in this study. The results indicated that through the bioaugmentation by Rhizobium sp. NJUST18, CSFDMBR could be successfully started, which was confirmed by complete removal of pyridine, efficient nitrification, and significant increase of biomass. Pyridine could be effectively degraded in the CSFDMBR even at influent pyridine loading rate as high as 9.0 kg m−3 day−1, probably due to the efficient biomass retention in the CSFDMBR, which could be attributed to the formation of aerobic granules and the key role of dynamic membrane. CSFDMBR presented good polishing performance in treating pyridine wastewater, with effluent total organic carbon (TOC) and turbidity as low as 22.5 ± 6.8 mg L−1 and 3.8 ± 0.5 NTU, respectively. Membrane fouling could be effectively controlled, as indicated by backwash period as long as 60 days. The observed efficient performance highlights the potential for the full-scale application of the bioaugmented CSFDMBR, particularly for highly recalcitrant pollutant removal.

Volatile fatty acids (VFAs) production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow hydrolysis and/or poor substrate availability. Increased attention has been given to enhance the hydrolysis and acidification of WAS recently. This study presented an efficient and green strategy based on the combined use of nitrite pretreatment and alkaline pH to stimulate hydrolysis and VFA accumulation from WAS. Results showed that both proteins and polysaccharides increased in the presence of nitrite, indicating the enhancement of sludge solubilization and hydrolysis processes. Mechanism investigations showed that nitrite pretreatment could disintegrate the sludge particle and disperse extracellular polymeric substances (EPS). Then, anaerobic digestion tests demonstrated VFA production increased with nitrite treatment. The maximal VFA accumulation was achieved with 0.1 g N/L nitrite dosage and pH 10.0 at a sludge retention time (SRT) of 7 days, which was much higher VFA production in comparison with the blank, sole nitrite pretreatment, or sole pH 10. The potential analysis suggested that the combined nitrite pretreatment and alkaline pH is capable of enhancing WAS digestion with a great benefit for biological nutrient removal (BNR).

The activated carbon fiber(ACF) was prepared from polyacrylonitrile-based pre-oxidized fiber(PANOF) by KOH direct activation. The influence of activation conditions including impregnation ratio(the mass ratio of PANOF to KOH), activation temperature and activation time on the pore structure and electrochemical properties of ACF was investigated, and the corresponding activation mechanism was proposed. The ACF prepared at an activation temperature of 800 °C and an impregnation ratio(the mass ratio of PANOF to KOH) of 1:2 for an activation time of 1 h in 6 mol/L KOH solution exhibits a specific surface area of 3029 m2/g, a mesoporosity of 84.2% and a specific capacitance of 288 F/g, and shows a good capacitive performance. The prepared ACF can be used as the electrode material for supercapacitors.

The highly recalcitrant 1H-1,2,4-triazole (TZ) is widely used in the synthesis of agricultural pesticide and considered to be an environmental pollutant. In this study, a novel strain NJUST26 capable of utilizing TZ as the sole carbon and nitrogen source, was isolated from TZ-contaminated soil, and identified as Shinella sp. The biodegradation assays suggested that optimal temperature and pH for TZ degradation by NJUST26 were 30 °C and 6–7, respectively. With the increase of initial TZ concentration from 100 to 320 mg L−1, the maximum volumetric degradation rate increased from 29.06 to 82.96 mg L−1 d−1, indicating high tolerance of NJUST26 towards TZ. TZ biodegradation could be accelerated through the addition of glucose, sucrose and yeast extract at relatively low dosage. The main metabolites, including 1,2-dihydro-3H-1,2,4-triazol-3-one (DHTO), semicarbazide and urea were identified. Based on these results, biodegradation pathway of TZ by NJUST26 was proposed, i.e., TZ was firstly oxidized to DHTO, and then the cleavage of DHTO ring occurred to generate N-hydrazonomethyl-formamide, which could be further degraded to biodegradable semicarbazide and urea.

A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating resin for Pb2+ were studied by batch adsorption, and the adsorption process was analyzed from thermodynamics and kinetics aspects. The adsorption mechanism of Pb2+ on the modified D401 chelating resin was discussed by FT-IR spectrometry. Experimental results show that in the Pb2+ concentration range of 200–400 mg/L, the adsorption capacities of the modified D401 chelating resin for Pb2+ increase by 77%–129%, and Langmuir isothermal adsorption model is more suitable for the equilibrium adsorption data. Adsorption is an endothermic process that runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best pH value under adsorption condition is 4–5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the adsorption capacity remains stable after five consecutive adsorption-desorption cycles. The maximal static saturated adsorption capacity of the resin is 206 mg/g at 333 K in the Pb2+ concentration range of 200–400 mg/L. The modified D401 chelating resin is an efficient adsorbent for the removal of Pb2+ from its single-metal ion solution.