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Quaternary ammonium compounds (QACs) are well‐known for their antimicrobial properties, but their widespread use is limited due to suboptimal antimicrobial efficiency and safety concerns. Recent progress in materials science has paved the way for the development of QAC‐based composites (QACCs). QACCs with diverse compositions have shown enhanced antimicrobial effectiveness and biosafety for various applications, such as food packaging, capacitive deionization, and household antimicrobials. This review provides a comprehensive summary of the synthesis approaches and different types of QACCs. Moreover, this review examines their antimicrobial applications, taking the underlying structure‐activity relationship into consideration. In addition, this perspectives are presented on the remaining challenges and future research directions for the further development of QACCs. It is expected that this review will provide a valuable reference for the design of next generation QACC‐based antimicrobial agents. [ABSTRACT FROM AUTHOR]

Bacterial infection is a major threat to public health. Nanotechnology offers a solution by combining nanomaterials with antibacterial agents. The development of an effective nanocomposite against drug‐resistant bacteria such as methicillin‐resistant Staphylococcus aureus (MRSA) is highly important yet challenging. Here, an anti‐MRSA core–shell structure is designed, containing antibacterial zeolitic imidazolate framework‐8 (ZIF‐8) as the core and bactericidal benzalkonium chloride (BAC) templated rough‐surface mesostructured silica nanocomposite (RMSN) as the shell. The resultant ZIF‐8@RMSN nanocomposite exhibits sustained release of BAC and zinc ions, effective disruption of the bacterial membrane, generation of oxidative damage of bacterial DNA, leakage of intracellular components, and finally bacterial death. Furthermore, the synergistic antibacterial mechanisms lead to enhanced biofilm elimination performance. In addition, the ZIF‐8@RMSN‐modified band‐aid effectively combats MRSA infection in vivo. This work has provided a promising nanocomposite against MRSA‐related infections. [ABSTRACT FROM AUTHOR]

This study empirically examines the impact of business environments on trade partners' economic growth using the Ease of Doing Business Score of the World Bank's Doing Business project for 2004–2018. The results show that with a threshold level of economic development, business environments have a significant positive impact on trade partners' economic growth, which is the spatial spillover effect of the business environment. Further, we find that this effect is heterogeneous, and it is much easier for a more developed country to drive the economic growth of less developed countries. [ABSTRACT FROM AUTHOR]

The article discusses the development of a core-shell structured nanocomposite that can effectively combat antibiotic-resistant bacterial infections. The nanocomposite consists of a zeolitic imidazolate framework (ZIF-8) as the core and a rough-surface mesostructured silica nanocomposite (RMSN) containing benzalkonium chloride (BAC) as the shell. The nanocomposite releases BAC and zinc ions, which enhance its antibacterial properties and ability to eliminate biofilms. The modified antibacterial band-aid made with this nanocomposite demonstrates excellent efficacy against drug-resistant bacterial infections both in laboratory tests and in vivo. [Extracted from the article]

Nucleic acid delivery in hard-to-transfect macrophages have attracted increasing attention in diverse applications such as defence against bacterial infection. Regulated by microenvironments in specific applications, macrophages have a heterogenous nature and exist in different phenotypes with diverse functions, e.g., pro-inflammatory and anti-inflammatory. However, it is not clear whether macrophage phenotype affects nucleic acid delivery, and which one is harder to transfect, and the design of nucleic acid carriers in harder-to-transfect macrophage phenotypes is largely unexplored. Herein, it is first revealed that nucleic acid delivery efficacy in macrophages is influenced by phenotype: IL-4-treated "M2-like" macrophages with suppressed mammalian target of rapamycin complex 1 (mTORC1) levels are harder-to-transfect than "M1-like" macrophages for mRNA and DNA. This knowledge is then translated to the purpose-design of gene delivery carriers for harder-to-transfect M2 phenotype macrophages dominant upon bacteria immune evasion. By loading chloroquine in tetrasulfide bond-containing organosilica nanoparticles, the resultant composite promotes macrophage M2 polarization to M1 and increases mTORC1 levels for enhanced translation. The design is demonstrated in vitro and in vivo for pathogenic Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) infections. It is expected that the findings may provide new knowledge and gene delivery solutions in other applications where the M2 phenotype macrophage is dominant., (© 2024 Wiley‐VCH GmbH.)