Latest ArticlesPhotodynamic therapy (PDT) has been gaining popularity in both scientific research and clinic applications due to its non-invasiveness and spatiotemporal targeting properties. Nevertheless, the local hypoxic microenvironment in tumor tissue impedes PDT universality. To overcome this drawback, a 2-pyridone-bearing BODIPY photosensitizer was synthesized rationally and introduced to polyethyleneglycol-b-poly(aspartic acid) to form a photosensitizer-1O2 generation, storage/release agent dual-loading system (PEG-b-PAsp-BODIPY). The investigation of the PDT effect at different illumination conditions in vitro and in vivo revealed that the system tremendously inhibited tumor proliferation, indicating that this new PEG-b-PAsp-BODIPY could act as a potentially effective photo therapeutic system for cancer therapeutics.
Metal-organic framework materials (MOFs), such as zeolitic imidazolate framework (ZIF), have been widely used in energy storage due to their advantages such as high structural stability, large specific surface, more active sites and skeleton structures. Herein, a novel two-dimensional (2D) CoCu-ZIF was synthesized by a facile solvothermal method. The as-prepared CoCu-ZIF nanosheets exhibit an ultrahigh reversible capacity of 2287.4 mAh/g and remains at 1172.1 mAh/g after 300 cycles at a current density of 100 mA/g, far better than that of the single Co-ZIF and Cu-ZIF. Additionally, the specific discharge capacity of CoCu-ZIF nanosheets can maintain at about 590 mAh/g after 1000 cycles at the current density of 2 A/g. Owing to the synergistic effect of two metals, function of nitrogen in the molecular and self-assembly 2D nanosheets, our research can provide strong support for the practical application of CoCu-ZIF materials in lithium ion batteries.
The selection and development of cathode of alkaline zinc batteries (AZBs) is still hindered and often leads to poor rate capability and short cycle life. Here, amorphous hollow nickel-cobalt-based sulfides nanocages with nanosheet arrays (AM-NCS) are designed and constructed with ZIF-67 as the self-template to exchange with Ni2+ and S2− by using a two-step ion exchange method. The synthesized AM-NCS possess the high specific capacity (160 mAh/g at 2 A/g), and the assembled battery has excellent rate performance (146 mAh/g reversible capacity at 5 A/g). The assembled device has excellent rate performance (155 mAh/g at 2 A/g) and long cycling stability (7000 cycles, 62.5% of initial capacity). The excellent electrochemical properties of the electrode materials are mainly attributed to the unique structure, in particular, polyhedron structure with hollow structure can improve the cyclic stability, and the amorphous structure can expose more reactive sites on the surfaces of nickel, cobalt and sulfur. This work provides a new strategy for the design and fabrication of high performance cathode materials for AZBs.
Metabolites can directly reflect and modulate cell responses and phenotypical changes by influencing energy balances, intercellular signals, and many other cellular functions throughout the lifespan of cells. Taking into account the heterogeneity of cells, single-cell metabolite analysis offers an insight into the functional process within one cell. Microfluidics as a powerful tool has attracted significant interest in the single-cell metabolite analysis field. The microfluidic platform is possible to observe, classify, and stimulate individual cells. It can also transport single-cell to subsequent analysis steps in a fast and controllable way to determine and analyze the composition and content of metabolites. The reviews of topics in microfluidics for single-cell metabolite analysis have been published in the past few years. However, most of them focused on metabolite analysis with mass spectrometry. Here, we covered the advances of microfluidic devices for single-cell metabolite analysis, with a focus on single-cell isolation and manipulation. What is more, we summarized the detection methods and applications of single-cell metabolites.
Mn-Si-MEL zeolite was developed as a bi-functional adsorption-catalytic oxidation material for volatile organic compounds (VOCs) elimination due to its good hydrophobicity & good organophileproperty brought by the substitution of Mn for Al in zeolite and the superior catalytic oxidation property endowed by the existence of Mn species. Various Mn-Si-MEL samples were obtained by introducing Mn to MEL crystallization system via different ways. It was found the incorporated Mn ways have a significant effect on the behavior of Mn being involved in the crystallization of MEL and finally influenced the distribution of Mn in zeolite as well the physicochemical properties of product zeolite. The seeding method (Mn-S2(Seed)) is favorable for the good incorporation and uniform distribution of Mn in zeolite while both recrystallization method (Mn-S2(RC)) and direct synthesis method (Mn-S2(DH)) are favorable for obtaining more reducible Mn species and surface adsorbed oxygen species. The Mn amount incorporated into zeolite follows Mn-S2(RC) (1.96 wt%) > Mn-S2(Seed) (1.07 wt%) ≈ Mn-S2(DH) (0.97 wt%), the adsorption capacity of various samples follows Mn-S2(Seed) (83.3 μmol/g) ≈ Mn-S2(RC) (82.1 μmol/g) > Mn-S2(DH) (76.1 μmol/g), while the catalytic oxidation ability of three samples follows Mn-S2(RC) ≈ Mn-S2(DH) > Mn-S2(Seed). Furthermore, Mn-S2(RC) which exhibits both superior adsorption capacity and catalytic oxidation ability shows good hydrophobicity and superior recyclability, demonstrating its great potential to be applied in the VOCs elimination by an enrichment-degradation route.
Neuromuscular blocking agents (NMBAs) are extensively used during anesthesia to improve surgical conditions by relaxing skeletal muscle movements. Rapid neuromuscular recovery after surgery is desirable to facilitate the recovery of muscle function and prevent residual blockade. Decamethonium (C10) is a classic NMBA, which has been restricted over the past decades ascribed to lack of a suitable antidote in clinic. Herein we used carboxylatopillar[6]arene (CP6A) to reverse neuromuscular blocker effect of C10 through direct host-guest encapsulation. NMR and isothermal titration calorimetry served to confirm the complexation between CP6A and C10 with robust affinity [(1.07 ± 0.14) × 107 L/mol]. The CP6A was further used as a reversal agent of C10, which facilitated to decrease C10 concentration in mice blood and excrete via urinary clearance, resulting in rapid recovery from muscle relaxation. These favorable outcomes might lead us to suggest that this supramolecular strategy could allow patients to regain lucidity much faster than spontaneous recovery from anesthesia.
Gestational diabetes mellitus (GDM), a frequently-occurring disease during pregnancy, may cause some adverse healthy outcome of both mother and offspring. However, the knowledge about metabolite alterations during the pathogenesis and development process is limited. Here, a large longitudinal non-targeted metabolomics study of 195 pregnant women (64 women with subsequently developed GDM and 131 healthy controls) was conducted. Each participant provided urine samples at three timepoints during early, middle and late pregnancy, respectively. The metabolic profiles of 585 urine samples (195 × 3) were measured by using ultra-high performance liquid chromatography coupled with Orbitrap high-resolution mass spectrometry. Among the 56 identified metabolites, the levels of eight metabolites increased and three ones decreased in the first trimester, the concentration of one metabolite increased and those of 20 decreased in the second trimester, as well as the levels of five metabolites increased and two decreased in the third trimester. After false discovery rate correction, the levels of valine and 5-acetamidovalerate in GDM group significantly increased in the first trimester, the levels of 1-methylguanine and 1, 3-dihydro-(2H)-indol-2-one significantly decreased in the second trimester and three metabolites (threonine, OH-octanedioyl-carnitine and pimelylcarnitine) increased and N-acetyltryptophan decreased in the third trimester, respectively. Six metabolites, such as pantothenic acid and threonine, had significant interaction effects between gestational stage (different trimester) and group (GDM or control). The differential metabolites were involved in "tryptophan metabolism", "purine metabolism", "valine, leucine and isoleucine degradation" and other pathways. The findings may provide insights into further pathogenesis study of GDM.
Bismuth-rich Bi5O7Br is a promising photocatalyst for pollutant removal owing to its stability and appropriate band structure in comparison with bismuth oxybromide. However, bulk-phase Bi5O7Br suffers from poor light absorption and high charge recombination rates resulting in poor activity. Elemental doping is a powerful strategy to enhance photocatalytic activity. In this study, we prepared a series of Br auto-doped ultrathin Bi5O7Br nanotubes and explored the effect of Br doping on photocatalytic NO removal. The optimal doping content was determined via a photocatalytic NO removal experiment, which revealed the optimal ratio of Bi and Br was approximately 3:1. In situ diffuse reflectance infrared Fourier transform spectroscopy (In situ DRIFT) and density functional theory (DFT) studies revealed that NO removal mechanism catalyzed by Br doped Bi5O7Br. Our work presents a new strategy for the enhancement of photocatalytic pollutant degradation by bismuth oxyhalide photocatalysts.
Transition metal selenides attract significant attention as advanced anode materials for sodium-ion batteries (SIBs) in recent years due to their appropriate working potential and high theoretic capacity. However, the poor structural stability and rate capability limit their further practical applications. Herein, zeolite imidazole framework-8/zeolite imidazole framework-67 is used as a template to prepare Co0.85Se and ZnSe nanoparticles embed in N-doped carbon matrix successfully, and then coated a carbon layer (ZCS@NC@C) by in-situ polymerization. One side, the N-doped carbon matrix with rich pore structure not only shorten the diffusion path of Na+ and improve the conductivity of the electrode, but also prevent structural collapse and agglomeration of active particles during the sodium insertion/extraction process. On the other side, the carbon shell preparation by coating can form a protective layer to buffer the volumetric stress generated in the electrochemical process and further improve the electrical conductivity. As a result, the as-prepared ZCS@NC@C anode material exhibits an excellent electrochemical performance for SIBs. This investigation provides a promising approach to optimize the electrochemical performance of SIBs by incorporating active metal compounds into conductive carbons to form multidimensional structure.
Semiconductor electrocatalysis with weak conductivity can accumulate extremely high carriers at semiconductor-electrolyte interface by self-gating effect, which strongly promotes electrocatalytic efficiency. The correlation between semiconductor carrier mobility and electrocatalysis performance is still unclear. Herein atomic-thin transition metal dichalcogenides based composites have been developed for hydrogen evolution reaction (HER) performed with on-chip microdevices. Electrical and electrochemical measurement of individual flack verified the key role of high carrier mobility for enhanced HER activity. Carrier mobility regulation further demonstrated its high dependence with HER performance under self-gating. Our study provides new insight into the carrier mobility of the semiconductor in the electrocatalysis, paving the way for designing high-performance semiconductor catalysts.