Construction of Z-scheme AgCl/BiOCl heterojunction with oxygen vacancies for improved pollutant degradation and bacterial inactivation.

A facile Z-scheme AgCl/BiOCl heterojunction photocatalyst with oxygen vacancies was fabricated by a water-bath method. The structural, morphological, optical and electronic properties of as-synthesized samples were systematically characterized. The oxygen vacancies were confirmed by EPR, which could optimize the band-gap of the AgCl/BiOCl heterojunction and improve the photo-induced electron transfer. The optimized AgCl/BiOCl heterojunction showed excellent photocatalytic degradation efficiency (82%) for tetracycline (TC). Simultaneously, E. coli was completely inactivated within 60 min due to the AgCl/BiOCl heterojunction. The elevated catalytic activity of the optimal AgCl/BiOCl heterojunction was ascribed to the synergistic effect of the enhanced light absorption and effective photoinduced charge carrier separation and transfer. Moreover, the degradation efficiency of the AgCl/BiOCl heterojunction towards ofloxacin, norfloxacin and Lanasol Red 5B was 73%, 74% and 96%, respectively. The experimental factors for the degradation efficiency of TC were also studied. Furthermore, active species trapping experiments indicated that superoxide radicals (˙O2-) were the main reactive species, and the Z-scheme charge transfer mechanism helped to improve the photocatalytic activity.

Research Note: Isolation and immunomodulatory activity of bursal peptide, a novel peptide from avian immune system developments.

The bursa of Fabricius (BF) is pivotal for B lymphocyte ontogenesis. In the present investigation, a novel bursal peptide, designated BP7, was extracted from BF and was found to stimulate colony-forming unit pre-B (CFU pre-B) formation at various concentrations (1 µg/mL, P < 0.05; 5 µg/mL, P < 0.05; 25 µg/mL, P < 0.05). Moreover, BP7 modulated B cell differentiation pathways. The immunoregulatory potential of BP7 was further assessed in avian and murine models subjected to immunization with inactivated avian influenza virus (AIV, H9N2 subtype). BP7 significantly augmented AIV-specific antibody levels (Prime immunization: 5 mg/kg, P < 0.05; Boost immunization: 0.4, 1, and 5 mg/kg, P < 0.05) and cytokine secretion in the avian model (IL-4 and IFN-γ: 0.4, 1, and 5 mg/kg, P < 0.05). Similarly, in the murine model, AIV-specific antibody levels (Prime and Boost immunization: 0.4, 1, and 5 mg/kg, P < 0.05) and cytokine production (IL-4 and IFN-γ: 0.4, 1, and 5 mg/kg, P < 0.05) were notably enhanced. This study offers novel insights into the mechanisms underlying B cell maturation and holds implications for future immunopharmacological interventions.

Construction of a novel two-dimensional AgBiO3/BiOBr step-scheme heterojunction for enhanced broad-spectrum photocatalytic performance.

Efficient S-scheme heterojunction photocatalysts were prepared through in situ growth of AgBiO3 on BiOBr. The self-assembled hierarchical structure of AgBiO3/BiOBr was formed from flower-like AgBiO3 and plate-like BiOBr. The optimized AgBiO3/BiOBr heterojunction possessed excellent visible-light photocatalytic degradation efficiency (83%) for ciprofloxacin (CIP) after 120 min, with 1.46- and 4.15-times higher activity than pure AgBiO3 and BiOBr, respectively. Furthermore, the removal ratio of multiple organic pollutants including tetracycline, Rhodamine B, Lanasol Red 5B and methyl orange was also investigated. Environmental interference experiments demonstrated that high pollutant concentrations, low photocatalyst dose and the addition of ions (SO4 2-, PO4 3-, HPO4 2-, H2PO4 -) inhibited the photocatalytic activities. Subsequently, a simultaneous degradation experiment showed the competitive actions between CIP and RhB for radicals, decreasing the photocatalytic activity of CIP. Furthermore, trapping and electron spin resonance experiments showed that h+ and ˙O2 - played a certain role in the degradation process and that ˙OH acted as assistant.