Latest ArticlesProgrammed cell death protein 1/programmed cell death 1 ligand 1(PD-1/PD-L1) protein-protein interaction represents an appealing target for cancer therapy. Several antibody drugs have been developed to target this interaction, but they are less effective in the treatment of melanoma. To overcome the limitations, the first proteolysis-targeting chimeric (PROTAC) small molecules simultaneously targeting PD-L1 and Src homology phosphotyrosyl phosphatase 2 (SHP2) were designed. By employment of PD-1/PD-L1 inhibitors BMS01 or BMS-37, SHP2 inhibitor SHP099 and E3 ligase ligands, a series of potent PD-L1 and SHP2 dual PROTACs were synthesized. The most promising compounds BS-7C-V2 and BS327V2 efficiently induced PD-L1 and SHP2 degradation and demonstrated significantly improved immune potency in B16-F10 and A375 cell lines. More importantly, the efficacy of BS-7C-V2 and BS327V2 in a B16-F10 transplanted mouse model was further evaluated based on their degradation ability in vivo. Taken together, our work qualifies the new dual PROTACs as a potent degrader of PD-L1 and SHP2. The biological and mechanism investigations with BS-7C-V2 and BS327V2 prove that dual PROTACs can play an anti-tumor role in vivo and in vitro, and can provide a new therapeutic strategy for melanoma.
Proteolysis-targeting chimera (PROTAC) has emerged as an efficient strategy to accurately control intracellular protein levels. However, conventional PROTACs are generally limited by nonspecific protein degradation and off-tissue side effects. Particularly, there is a lack of effective chemical tools for visualizing protein degradation. Herein, a near-infrared fluorescent and theranostic PROTAC (PRO-S-DCM) was designed for imaging the degradation of bromodomain-containing protein 4 (BRD4). PRO-S-DCM could be tumor-specifically activated and exhibited favorable imaging effects both in vitro and in vivo. PRO-S-DCM was proven to be a theranostic probe, which potently inhibited growth, invasion and migration of HeLa cells and induced cell apoptosis.
The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching (ACQ). In this study, an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters (Au NCs). Interestingly, the gold ion complexes coated with proteins of low isoelectric point (pI) nucleate at the secondary structure of proteins with high pI through ionic exchange within cells, generating fluorescent Au NCs. It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs, the distance between Au NCs can be controlled, avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ. This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects. Therefore, this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.
Although the powder Fenton-like catalysts have exhibited high catalytic performances towards pollutant degradation, they cannot be directly used for Fenton-like industrialization considering the problems of loss and recovery. Therefore, the membrane fixation of catalyst is an important step to realize the actual application of Fenton-like catalysts. In this work, an efficient catalyst was developed with Co-Nx configuration facilely reconstructed on the surface of Co3O4 (Co-Nx/Co3O4), which exhibited superior catalytic activity. We further fixed the highly efficient Co-Nx/Co3O4 onto three kinds of organic membranes and one kind of inorganic ceramic membrane installing with the residual PMS treatment device to investigate its catalytic stability and sustainability. Results indicated that the inorganic ceramic membrane (CM) can achieve high water flux of 710 L m-2 h-1, and the similar water flux can be achieved by Co-Nx/Co3O4/CM even without the pressure extraction. We also employed the Co-Nx/Co3O4/CM system to the wastewater secondary effluent, and the pollutant in complicated secondary effluent could be highly removed by the Co-Nx/Co3O4/CM system. This paper provides a new point of view for the application of metal-based catalysts with M-Nx coordination in catalytic reaction device.
Graphene quantum dots (GQDs) are a class of promising carbon-based nanomaterials that have attracted considerable interest from researchers due to their excellent physical, chemical, and biological properties. However, the high cost, toxicity, and laborious preparation process of GQDs also limit their widespread use. To address this issue, the actual research directions consist in replacing traditional non-renewable feedstocks via screening cheap, easily available, and renewable biomass materials based on the concept of resource conservation and environmental friendliness. Herein, the state-of-the-art technologies in the green preparation of GQDs using biomass as carbon source are reported. Initially, the green synthesis strategies as well as the structural, optical, and biosafety properties of GQDs are discussed in detail. Subsequently, the most representative applications of GQDs in energy and environmental remediation fields are summarized. Finally, the current challenges and future potential of the GQDs are presented.
Pollutants contained in wastewater pose serious harm to the environment. Graphene-based water treatment materials show significant advantages in wastewater treatment. However, with the development of graphene-based materials, its progress in water treatment has reached a bottleneck. The challenge lies in effectively enhancing its performance in water treatment and ensuring its practicality. By employing biomimetic approaches, some exceptional properties and structures found in nature can be mimicked in graphene materials, effectively enhancing graphene’s adsorption and mechanical properties. Current biomimetic methods include biomimetic mineralization, self-assembly, and templating. unfortunately, all of the above methods suffer from the disadvantages of complexity and poor bionic effect. Nevertheless, 3D printing, a form of additive manufacturing (AM) technology, offers integrated molding and excellent biomimetic performance in creating biomimetic materials. This paper will cover the following aspects: (1) An overview of objects suitable for bionics in terms of functional and structural aspects, along with their properties, and a discussion of various bionic objects combined with graphene materials in water treatment and related research; (2) a comparison of different methods for preparing graphene-based bionic materials; (3) an examination of the current drawbacks and limitations of graphene-based biomimetic materials; and (4) a conclusion and future prospects, exploring the potential of using 3D printing technology to produce graphene biomimetic materials. This review aims to serve as a guide for effectively leveraging natural inspirations to create graphene-based biomimetic materials and enhance graphene properties.
Small interfering RNA (siRNA), a promising revolutionary therapy, faces delivery obstacles due to its poor targeting, strong charge negativity and macromolecular nature. Clinical-approved siRNAs can now only be delivered to the liver mediated by the chemically conjugated N-acetylgalactosamine (GalNAc) ligand, the conjugate can be effectively uptaken into cells through interaction with asialoglycoprotein receptor (ASGPR) highly expressed on liver hepatocytes. To further explore an efficient non-hepatic targeted delivery strategy, in this study, we designed a delivery system that chemically conjugated p53 siRNA to renal tubular cell-targeting peptides for targeting the kidney, which was suitable for industrial transformation. Results showed that peptide-siRNA conjugate could specifically enter renal tubular epithelial cells and silence target genes. In cisplatin-induced acute kidney injury (AKI) mice, peptide-siRNA conjugate blocked the p53-mediated apoptotic pathway and alleviated renal damage. The innovative proposed system to conjugate kidney-targeting peptides with siRNA achieved the efficient kidney-targeted delivery of siRNA and provided a prospective choice for treating AKI.
Covalent organic frameworks (COFs) are crystalline porous polymeric materials composed of organic monomers connected by strong covalent bonds and offer high stability, good crystallinity, a large specific surface area, and controllable structures. COFs are widely used in the fields of adsorption and separation, catalysis, photovoltaics, and drug-delivery. The structural regulation and performance optimization of COFs can be realized through the modification of ligands and the selection of linkage methods. In which, the types of linkage are closely related to the stability and performance of COFs. In this review, nitrogen-containing linkage-bonds (NCLBs) in COFs are divided into N-containing double bonds, N-containing conjugated rings and N-containing unconjugated rings. The association between structure and performance of COFs is elaborated and the synthesis methods of COFs are systematically summarized. Moreover, the structural design, theoretical prediction and machinable application of COFs are prospected
Metal halide perovskite nanocrystals (MHP NCs) are of great candidates in photocatalytic applications due to their extreme light utilization efficiency. However, the instability towards humid environment severely restrict their practical application. Herein, the CsPbBr3/CsPb2Br5 heteronanocrystals (HNCs) were successfully encapsulated into ZIF-8 through a thermal injection method via controlling the molar ratio of Cs+/Pb2+. The surface of ZIF-8 was then modified with hydrophobic copolymer of poly(methyl methacrylate) (PMMA) to improve the water stability. Benefiting from the intimate interfacial interaction and staggered energy band structure, the type-Ⅱ heterojunction of CsPbBr3/CsPb2Br5 guarantees efficient separation and migration of photogenerated electron/hole pairs. Meanwhile, the formation of Z-scheme heterojunction between ZIF-8 and CsPbBr3/CsPb2Br5 HNCs contributes to the adsorption and enrichment of pollutants, further accelerates the photocatalytic antibiotic degradation efficiency towards tetracycline hydrochloride (TCH) in aqueous solution. Nearly 87% of TCH (40 mg/L, 50 mL) was degraded by 40 mg catalyst within 100 min. This work offers a feasible approach in assembling high-performance MHP NCs-based efficient photocatalyst with expanding application in aqueous solution.
Studies widely acknowledge the enhancement of permanganate (Mn(Ⅶ)) oxidation of organic contaminants by coexisting matrices in water. This study investigated the positive influence of Mn(Ⅱ), a common soluble metal ion, on the removal of trace organic pollutants by Mn(Ⅶ). Results showed that introducing 20 µmol/L Mn(Ⅱ) at pH 5.0 accelerated trace organic pollutant removal by promoting colloidal MnO2 formation. UV−vis spectrum, quenching, and probe experiments confirmed role of MnO2 in sulfamethoxazole (SMX) oxidation, with Mn(Ⅲ) playing a predominant role. Meanwhile, in situ-generated MnO2 facilitated Mn(Ⅶ)* formation, enhancing oxidation performance, as indicated by Raman spectroscopy and electrochemical analysis. Eleven transformation products (TPs) of SMX in the Mn(Ⅶ)/Mn(Ⅱ) process were detected by UPLC-QTOF-MS/MS. Subsequently, the reaction pathways of SMX were elucidated through Fukui index analysis and the identification of TPs. Additionally, toxicity simulations with Toxicity Estimation Software Tool (T.E.S.T.) software revealed significantly lower cytotoxicity of TPs of SMX compared to the parent compound. This study unveils an effective strategy to enhance Mn(Ⅶ)-mediated degradation of organic pollutants in water, elucidating Mn(Ⅱ)-induced Mn(Ⅶ) activation mechanisms.