Latest ArticlesSodium percarbonate (Na2CO3·1.5H2O2, SPC) has been extensively employed as a solid substitute of H2O2 for Fenton process in water treatment, because of its high stability during the production, transport, storage and usage. In addition, SPC can be applied in a wider range of work pH, it is also applied as a buffer in Fenton reaction for preventing a drop in pH. Herein, we have synthesized basic copper molybdate (BCM) nanoblocks with the molecular formula of Cu3(MoO4)2(OH)2 as an efficient and heterogeneous catalyst for antibiotics degradation via percarbonate activation. First, fully physical characterizations confirmed BCM nanocomposite exhibited a structure of nanoblocks. We also found that BCM/SPC system could work in a much wider pH range, compared with H2O2. Then, BCM/SPC system presented a good anti-interference ability for natural organic matter in OTC degradation. EPR results and Quenching tests confirmed that the co-presence of ·CO3−, ·O2−, 1O2 and ·OH in BCM/SPC system.
Spin-orbit, charge-transfer intersystem crossing (SOCT-ISC) can directly overcome the disadvantages of the traditional heavy-atom effect and improve the generation efficiency of reactive oxygen species (ROS). Since orthogonal molecular orbitals of donor-acceptor (D-A) pairs favor the SOCT-ISC transition, herein aza-borondipyrromethenes (aza-BODIPYs) with 1,7-di-anthracyl groups (An-azaBDP) was successfully prepared, owing to steric hindrance to produce a big dihedral angle between the two molecular orbital (MO) planes. Moreover, according to density functional theory (DFT) and time-dependent density functional theory (TDDFT), the energy difference between the S1-T1 orbitals of An-azaBDP is small and more inclined towards ISC. An-azaBDP can effectively generate singlet oxygen under light irradiation. An-azaBDP with light irradiation can induce apoptosis in SW620 cells, and can serve as a potential candidate for the treatment of cancer cells and tumors.
Recently, non-centrosymmetric (NCS) Hg-based chalcogenides have garnered significant interest due to their strong second-harmonic-generation intensities (deff), making them attractive candidates for infrared nonlinear optical (IR-NLO) application. However, achieving both wide band gaps (Eg) and large phase-matched deff simultaneously in these materials remains a challenge due to their inherent constraints on each other. In this research, we have successfully obtained two quaternary NCS Hg-based chalcogenides, Rb2HgGe3S8 and Cs2HgGe3S8, by implementing a bandgap engineering strategy that involves alkali metal introduction and Hg/Ge ratio regulation. Both compounds consist of 2D [HgGe3S8]2– anionic layers made of 1D [HgGeS6]6– chains and dimeric [Ge2S6]4– polyhedra arranged alternately, and the charge-balanced Rb+/Cs+ cations located between these layers. Remarkably, Rb2HgGe3S8 and Cs2HgGe3S8 exhibit overall properties required for promising IR-NLO materials, including sufficient PM deff (0.55–0.70 × AgGaS2@2050 nm), large Eg (3.27–3.41 eV), giant laser-induced damage thresholds (17.4–19.7 × AgGaS2@1064 nm), broad optical transmission intervals (0.32–17.5 µm), and suitable theoretical birefringence (0.069–0.086@2050 nm). Furthermore, in-depth theoretical analysis reveals that the exceptional IR-NLO performance is attributed to the synergy effects of distorted [HgS4] and [GeS4] tetrahedra. Our study provides a useful strategy for enhancing the Eg and advancing Hg-based IR-NLO materials, which is expected to extended and implemented in other chalcogenide systems.
Post-synthetic installation strategy is an effective approach to improve the functions of metal-organic frameworks (MOFs). Herein, a pair of chiral MOFs is successfully constructed through solvothermal subcomponent self-assembly and exhibit circularly polarized luminescence (CPL). These MOFs contain coordinatively unsaturated Zn sites and channels, which allow the installation of pyridyl-terminated pillars into the original structure. Such a post-synthetic installation process reinforces the MOFs' rigidity and increases the photoluminescence quantum yields (PLQYs). Furthermore, the luminescence dissymmetry factors (glum) of these post-modified MOFs are amplified after installing the pillars. This work provides an appealing strategy for boosting the CPL performance of chiral MOFs.
The combination of interface engineering and defect engineering is a promising strategy for developing new semiconducting surface-enhanced Raman scattering (SERS) substrate. Herein, an organic/inorganic hybrid g-C3N4/TiO2-X heterojunction with synchronous generation of strong interface effect and abundant surface oxygen vacancy (OV) defect was prepared by a simple sol-hydrothermal procedure with a help of urea. Due to the improved substrate-to-molecule charge transfer (CT) from joint contribution of high-efficiency carrier separation induced by strong interface coupling effect and multiple CT paths derived from abundant surface OV, g-C3N4/TiO2-X substrate exhibits greatly enhanced SERS effect for non-resonant 4-mercaptobenzoic acid (4-MBA) probe. The enhancement factor of g-C3N4/TiO2-X substrate for 4-MBA is as high as 5.57 × 106, and the substrate exhibits ultra-high stability and excellent spectral reproducibility. More meaningfully, the developed g-C3N4/TiO2-X heterojunction can be used to execute an ultrasensitive detection for antibiotic residues in real water system, even comprehensive evaluation of multi-component residues.
Monosescinol A (1), the first example of sesquiterpene–polycyclic polyprenylated acylphloroglucinol (PPAP) adduct, which represented a new subclass of PPAP-type natural products, along with two new congeners with normal spiro 6/6/5 tricyclic architecture, were isolated from Hypericum longistylum. Monosescinol A possessed an unprecedented 6/5/5/6/6 pentacyclic carbon skeleton that might be assembled from the 6/6/5 carbon skeleton, via the splitting decomposition of C-3/C-14, and the attack from the C-3 in the PPAP core to C-28 in sesquiterpene section. In addition, we have firstly confirmed that 24R configuration was existed in sec–Bu containing PPAPs by single crystal diffraction data analysis of monosescinol B (2), that might provide an enlightenment in the configurational determination of sec–Bu containing PPAPs. Significantly, further pharmacological research has found that compound 1 exhibited remarkable pharmacological effects against acute myeloid leukemia (AML) cell lines, with direct inhibition of mitochondrial complex Ⅴ and an increase in mitochondrial membrane potential, and led to an induction of oxidative stress, endogenous inflammation, and apoptosis of AML cells.
Carbon dots (CDs), as a solid-state phosphor, have great potential for application in a new solid-state lighting device—laser diode (LD). For high efficiency LD devices, both high photoluminescence quantum yield (PLQY) and high photothermal stability of CDs are essential. Herein, yellow CDs@ZIF-8 composites with high structural stability were prepared by encapsulating CDs in zeolitic imidazolate framework-8 (ZIF-8) through electrostatic adsorption between CDs and ZIF-8, in which CDs with amino groups on the surface were used as luminescent feeders and ZIF-8 was used as a protective layer matrix. The as-prepared CDs@ZIF-8 not only possess a high PLQY of up to 81.17%, but also maintain a high fluorescence intensity of 100% and 80% under long-term illumination (60 min) and high temperature (478 K), respectively. The hydrogen bonding between CDs and ZIF-8 in the encapsulated structure can enhance the degree of electron cloud delocalization, which can improve the PLQY of CDs@ZIF-8. Meanwhile, CDs@ZIF-8 has high photothermal stability due to the binding effect of ZIF-8 on CDs and high thermal stability of ZIF-8. The white LD device, fabricated from CDs@ZIF-8 as a phosphor in combination with 450 nm blue LD, has a color coordinate of (0.37, 0.33), a color temperature of 3762 K, and a high color rendering index of 86. This study provides a new strategy for the construction of solid-state phosphors with high PLQY and high photothermal performance.
Chemotherapy has been recommended as the standard protocol for triple-negative breast cancer (TNBC) at the advanced stage. However, the current treatment is unsatisfactory due to inefficient drug accumulation and rapid chemo-resistance. Thus, rational design of advanced drug delivery systems that can induce multiple cell death pathways is a promising strategy to combat TNBC. Ferroptosis is a powerful non-apoptotic cell death modality, showing potential in tumor inhibition. Herein, we propose a binary prodrug nanoassemblies that combines chemotherapy with ferroptosis for TNBC treatment. In this system, paclitaxel is linked with paracetamol (ferroptosis activator) by a disulfide linkage to construct self-assembly prodrug. Meanwhile, 2-distearoyl-sn-glycerol-3-phosphoethanolamine-N-methyl(polyethylene glycol)-2000-tyrosine (DSPE-PEG2k-tyrosine) is applied for large neutral amino acid transporter 1 (LAT1) targeting, which is highly expressed in TNBC. The prodrug nanoassemblies exhibit good stability and a glutathione (GSH)-responsive release profile. Furthermore, the LAT1-targeted nanoassemblies show stronger cytotoxicity, higher cellular uptake, and more obvious ferroptosis activation than non-decorated ones. In a TNBC mice model, the prodrug nanoassemblies demonstrate strong anti-tumor efficacy. The application of ferroptosis-assisting chemotherapy may provide a promising strategy for TNBC therapy.
The application of nanotechnologies in formulation has significantly promoted the development of modern medical and pharmacological science, especially for nanoparticle-based drug delivery, bioimaging, and theranostics. The advancement of engineering particle design and fabrication is largely supported by a better understanding of how their apparent characteristics (e.g., size and size distribution, surface morphology, colloidal stability, chemical composition) influence their in vivo biological performance, which raises an urgent need for practical nanoformulation methods. Based on turbulent flow mixing and the self-assembly of molecules in fluids, flash technologies emerged as effective bottom-up fabrication strategies for effective nanoformulation. Among the flash technology family, flash nanocomplexation (FNC) is considered a novel and promising candidate that can promote and optimize formulation processes in a precise spatiotemporal manner, thus obtaining excellent fabrication efficiency, reproducibility and expandability. This review presents an overview of recent advances in fabricating drug-delivery nanoparticles using FNC platforms. Firstly, brief introductions to the basic principles of FNC technology were carried out, followed by descriptions of turbulent microvolume mixers that have significantly promoted the efficiency of FNC-based fabrications. Applications of real formulation cases were then categorized according to the self-assembly-driven interactions (including electrostatic interaction, coordination interaction, hydrogen bonding and hydrophobic interaction) and discussed to reveal the progressiveness of fabricating nanoparticles and discuss how its flexibility will provide advances and replenish the philosophy of nanomedicine formulation. In the end, the commercial potential, current limitations, and prospects of FNC technology for nanoformulation will be summarized and discussed.