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Various immune cell‐mediated drug delivery systems have been reported for precision medicine, but the proinflammatory differentiation of immunocyte vehicles can exacerbate disease progression, resulting in a formidable obstacle to efficacious pharmacotherapy. The progression of atherosclerosis is closely related to the recruitment of blood immunocytes into the plaques, as the migrated macrophages can differentiate into harmful foam cells, leading to dysregulation of macrophage immunity. In this study, a "Trojan horse" based on zombie macrophages (denoted as Z‐Møs) as a biomimetic drug delivery system (denoted as ZARMs) is constructed to regulate macrophage immunity inside plaques. Reactive oxygen species‐responsive nanoparticles (denoted as AR‐NPs) loaded with atorvastatin (denoted as ATT) are encapsulated into Z‐Møs to construct ZARMs. After intravenous administration, ZARMs selectively migrate into plaques, and insusceptible biological characteristics are kept even in the presence of high levels of ROS within the plaques, which simultaneously triggers ATT release from AR‐NPs loaded in Z‐Møs. Treatment assessments indicate that ZARMs can efficiently boost macrophage immunity to reduce the inflammatory burden by inhibiting the expression of CD47 on foam cells without the risk of detrimental domestication of immunocytes in the plaques. This Z‐Møs‐mediated drug delivery system may arouse an advanced therapeutic strategy for preventing atherosclerotic cardiovascular disease. [ABSTRACT FROM AUTHOR]

Escherichia coli (E. coli) is a common Gram-negative bacterium that is widely distributed in nature and is susceptible to natural and random genetic factors. It is a pathogenic factor for many diseases. Sensitive and specific detection of E. coli is an important means to ensure food safety and prevent foodborne disease outbreaks. Ultrasensitive and specific detection of E. coli is still an urgent problem that needs to be solved. An intuitive and convenient colorimetric assay method with high sensitivity based on a DNAzyme-powered AuNR-DNA walker is proposed here for detection of E. coli. The strategy, dependent on the targeted activation of Mg2+-DNAzyme, starts an efficient DNA walking machine, induces the formation of countless peroxidase-mimicking enzymes, and produces a color change via a chromogenic reaction for visual detection of E. coli. This strategy features several aspects. First, this is the first time that an AuNR-based DNA walker is integrated with a colorimetric assay of E. coli. By combining the DNAzyme-powered AuNR-DNA walker and visual detection via the peroxidase-mimicking enzyme, the detection sensitivity is significantly improved compared to those of previously reported colorimetric-based methods, which provides a paradigm for the development of highly sensitive colorimetric assay methods. Second, an activity-controlled nano-DNAzyme is constructed via target-triggered formation of G-quadruplex DNAzyme to achieve low background and high signal-to-noise detection. In addition, this strategy has the advantages of simple operation, short analysis time, low cost, and easy on-site detection. Therefore, the proposed strategy has the potential for application in the detection of E. coli and related food safety analysis and clinical diagnosis. [ABSTRACT FROM AUTHOR]

Atherosclerosis can form intimal plaques in the arteries and undergo plaque rupture with followed stroke or myocardial infarction under certain pathological conditions. However, suboptimal intraplaque accumulation, along with severe off‐target effects, remain formidable obstacles for efficient pharmacotherapy of atherosclerosis. A characteristic feature of the progression of atherosclerosis is the continuous recruitment of inflammatory monocytes that differentiate into foamy macrophages with the generation of legumain in the plaques. In this study, a bio‐activatable nano‐shuttle based on human serum albumin is conceived that contained curcumin to allow the precise inhibition of atherosclerosis progression. Following intravenous injection, the nano‐shuttles are almost exclusively engulfed by inflammatory monocytes in an efferocytosis‐mimetic manner and selectively co‐migrated with the monocytes towards the plaques. The nano‐shuttles are readily activated to release the initially arrested curcumin in response to the generation of legumain upon the differentiation of monocytes into foamy macrophages within the plaques. Treatment assessments on atheroprone apolipoprotein‐E‐deficient mice indicated that the nano‐shuttles substantially inhibit the progression of atherosclerosis by attenuating the plaque inflammation burden without any obvious adverse effects. The integration of highly selective accumulation and specific drug activation of the nano‐shuttles in plaques can arouse an advanced therapeutic strategy to prevent atherosclerotic cardiovascular disease. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have become stars in photovoltaics due to their rapidly increased efficiency. However, their stability is still below par due to moisture permeation from grain boundaries and defects. To conquer both problems at once, a passivation agent 3,4,5,6‐tetrafluorophthalicacid (TFPA) is rationally designed to heal both for not only improved cell efficiency but also better stability. It is found that the TFPA is prone to distribute along grain boundaries and has little influence within the bulk of the perovskite film. In addition, it appears that the TFPA helps to reduce the film roughness, to adjust the energy level, to facilitate hole transporting from perovskite to spiro‐OMeTAD, and to increase the hydrophobicity of the perovskite film, as it is demonstrated by the inhibited nonradiative recombination and prolonged carrier lifetime. Owing to strong interactions between F, ‐COOH, and Pb, the device with TFPA shows outstanding efficiency and stability. A perovskite solar cell with TFPA modification delivers a champion efficiency of 23.70% and a significantly enhanced stability that the device maintains 90% of its initial efficiency after 5200 h, among the best ambient stability. Herein, an effective strategy of grain boundary passivation is provided to improve the stability of perovskite solar cells. [ABSTRACT FROM AUTHOR]