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Quasi‐two‐dimensional (quasi‐2D) perovskites are emerging as efficient emitters in blue perovskite light‐emitting diodes (PeLEDs), while the imbalanced crystallization of the halide‐mixed system limits further improvements in device performance. The rapid crystallization caused by Cl doping produces massive defects at the interface, leading to aggravated non‐radiative recombination. Meanwhile, unmanageable perovskite crystallization is prone to facilitate the formation of nonuniform low‐dimensional phases, which results in energy loss during the exciton transfer process. Here, we propose a multifunctional interface engineering for nucleation and phase regulation by incorporating the zwitterionic additive potassium sulfamate into the hole transport layer. By using potassium ions (K+) as heterogeneous nucleation seeds, finely controlled growth of interfacial K+‐guided grains is achieved. The sulfamate ions can simultaneously regulate the phase distribution and passivate defects through coordination interactions with undercoordinated lead atoms. Consequently, such synergistic effect constructs quasi‐2D blue perovskite films with smooth energy landscape and reduced trap states, leading to pure‐blue PeLEDs with a maximum external quantum efficiency (EQE) of 17.32 %, spectrally stable emission at 478 nm and the prolonged operational lifetime. This work provides a unique guide to comprehensively regulate the halide‐mixed blue perovskite crystallization by manipulating the characteristics of grain‐growth substrate. [ABSTRACT FROM AUTHOR]

Two new mixed-ligand copper(ii) complexes, [Cu(PyTA)(l-Phe)Cl]·2H2O (1), [Cu(PyTA)(l-Met)Cl]·0.5H2O (2) (where PyTA = 2,4-diamino-6-(2′-pyridyl)-1,3,5-triazine, l-Phe = l-phenylalanine, l-Met = l-methionine), were synthesized and characterized by elemental analysis, IR, UV-vis, molar conductivity, ESI-MS, and X-ray crystal diffraction. The copper centers of complexes 1 and 2 are in slightly distorted square pyramidal environments, and fluorescence quenching experiments and calorimetry showed that the complexes bound to human serum albumin (HSA) with high affinities (binding constants KD = 3.71 × 106 L mol−1 for 1 and 1.99 × 106 L mol−1 for 2, 1 ＞ 2). UV-vis and circular dichroism (CD) spectroscopic investigations revealed that the complexes induced the alteration of hydrophobic environments and the decrease in the α-helix level of HSA during binding processes. Synchronous fluorescence spectra demonstrated that the binding sites of the complexes on HSA were close to the Trp-214 residue in the IIA subdomain, which was further verified by site marker competitive experiments and the molecular docking method. In vitro cytotoxicity experiments showed that the effective HSA-binding interactions enhanced the cytotoxicity of the complexes. Both 1 and 2 displayed strong anticancer activities against the Eca-109 cell line and induced cell death through the apoptosis pathway. [ABSTRACT FROM AUTHOR]

Perovskite light‐emitting diodes (PeLEDs) have garnered extraordinary attention in displaying field owing to their excellent luminescence properties. Although exogenous additives are extensively employed for optimizing PeLEDs, their comprehensive regulation including side effects still lacks in‐depth study. Here for the first time, it is demonstrated that the deprotonation degree of additives significantly influences the performance of blue PeLEDs. Benzenesulfonic acid (BSA) and ammonium benzenesulfonate (ABS) with similar molecular structures while distinctly different acid dissociation constants (pKa) are used for modifying blue perovskites. By comparison, high‐pKa ABS holds greater potential in boosting device performance, contributing to an improved peak external quantum efficiency of 18.8%. This discrepancy is ascribed to the fact that low‐pKa BSA is prone to induce prominent perovskite chlorine loss owing to its intense deprotonation, while high‐pKa ABS significantly suppresses chlorine vacancy formation. Meanwhile, the adsorption energy of organic spacer onto perovskite is greatly reduced due to the strong intermolecular hydrogen bonding with ABS, contributing to a concentrated phase arrangement for smooth exciton energy transfer. Additionally, ABS modification further suppresses trap‐mediated nonradiative recombination by coordinating with the undercoordinated lead (II) ions at grain boundaries. This work provides valuable guidelines for optimizing additive screening toward high‐performance blue PeLEDs. [ABSTRACT FROM AUTHOR]

Immunoassay for pesticides is an emerging analytical method since it is rapid, efficient, sensitive, and inexpensive. In this study, a recombinant antigen-binding fragment (Fab) against a broad set of O,O-diethyl organophosphorus pesticides (DOPs) was produced and characterized. The κ chain and Fd fragment were amplified via PCR and inserted into the vector pComb3XSS and the soluble Fab on phagemid pComb3XSS was induced by isopropyl β-d-thiogalactoside in E. coli TOP 10F’. SDS-PAGE, Western blotting, and indirect competitive ELISA results indicated that Fab maintained the good characteristics of the parental mAb. To better understand antibody recognition, the three-dimensional (3D) model of Fab was built via homologous modeling and the interaction between Fab and DOPs was studied via molecular docking and dynamics simulations. The model clearly explained the interaction manner of Fab and DOPs, and showed that the Arg-L96 and Arg-H52 were mainly responsible for antibody binding. This work provided a foundation for further mutagenesis of Fab to improve its characteristics. [ABSTRACT FROM AUTHOR]

Two new copper(II)-amino acid complexes, [Cu(PyTA)( l -Thr)(ClO 4 )] 2 ·1.5H 2 O ( 1 ) and [Cu(PyTA)( l -Arg)(ClO 4 )(H 2 O)]·ClO 4 ( 2 ) (PyTA = 2,4-diamino-6-(2-pyridyl)-1,3,5-triazine, l -Thr = l -threonine, l -Arg = l -arginine), were successfully synthesized and characterized. The results determined by single crystal X-ray diffraction showed that the five-coordinated copper of 1 and the six-coordinated copper of 2 were located in the distorted square-pyramidal and distorted octahedral environments, respectively. Spectroscopic titrations, thermal denaturation experiments, viscosity measurements revealed that the complexes bound to DNA via a groove binding mode, with the DNA-binding constants of 6.126 × 10 4 M −1 for 1 and 6.464 × 10 4 M −1 for 2 . Electrophoresis experiments revealed that the complexes cleaved pBR322 DNA by an oxidative pathway involving in the generation of superoxide free radical (O 2 − ). Multi-spectroscopic analyses showed that the complexes bound to site I of human serum albumin (HSA) with moderate affinities. In particular, in vitro cytotoxicities of the complexes against Bel-7402 cell line showed promising anticancer effects (IC 50 = 42.1 ± 1.7 μM for 1 ; IC 50 = 36.3 ± 0.9 μM for 2 ). In addition, the binding mechanism and mode of the complexes with DNA/HSA were verified by molecular docking technique. [ABSTRACT FROM AUTHOR]

Abstract: A series of Nd–TiO2 powders have been prepared by the sol–gel technique with neodymium nitrate and tetra-n-butyl titanium as raw materials, and then Nd–TiO2 nanotubes were fabricated by the hydrothermal method with a 10moll−1 NaOH solution. The as-prepared Nd–TiO2 nanotubes were characterized by TEM, XRD, DRS, and XPS, and their photocatalytic activity was also tested in the case of the degradation of methyl orange in water. TEM photograph showed that Nd–TiO2 nanotubes were about 10–20nm in diameter, with the lengths range from 100 to 300nm. TiO2 nanotubes contained anatase and rutile crystallites. However, 0.3% Nd–TiO2 nanotubes contained anatase crystallites, and only little rutile crystallites, so it is shown that neodymium doping hindered the phase transformation from anatase into rutile. Nd doping increased the visible-light absorption ability of Nd–TiO2 nanotubes, and a red shift for Nd–TiO2 nanotubes appeared when compared to TiO2 nanotubes. XPS analysis showed that two types of oxygen existed on the photocatalyst surface, including metal–O and hydroxyl group, and more hydroxyl group was on the surface of 2% Nd–TiO2 nanotubes than on the surface of TiO2 nanotubes. Nd doping enhanced the photocatalytic activities of Nd–TiO2 nanotubes, and 0.3% Nd–TiO2 nanotubes exhibited the highest photocatalytic activity. [Copyright &y& Elsevier]