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Lyophilization is a prevalent technique for preparing paclitaxel (PTX) clinical formulations. However, the instability of PTX nanoparticles poses challenges in producing lyophilized formulations. Such an instability involves maintaining stable dispersions and structural integrity during lyophilization. To tackle these issues, flash nanoprecipitation method is employed to prepare highly stable and loaded lyophilizable diPTX-SS nanoparticles, achieving over a month of nanosuspension stability and 91 wt % loading capacity. Furthermore, adjusting the concentrations and stabilizer ratios allows for controlled nanoparticle preparation with surface structures suitable for lyophilization. The hybridization of PLGA-PEG and DSPE-PEG increases the surface PEG layer content, creating a corona-like outer layer that maintains nanoparticle integrity during lyophilization, and ensures excellent redispersibility for postlyophilization without excessive cryoprotectants. Additionally, responsive release behavior, along with in vitro and in vivo experiments, confirms that these lyophilizable hybrid diPTX-SS nanoparticles effectively suppress tumor growth and vascular endothelial proliferation, offering insights for clinical PTX formulation development. [ABSTRACT FROM AUTHOR]

Pesticides are indispensable in agricultural development, but their effectiveness is often hindered by natural factors like rain‐off and degradation. Herein, tebuconazole nanopesticides (TEB NPs) with leaf‐adhesive, water‐stable, and small‐sized were successfully prepared by flash nanoprecipitation using the biodegradable polyethylene glycol‐b‐poly (lactic‐co‐glycolic acid) as a carrier. The nanopesticides could be efficiently deposited on plant leaves with uniform distribution and exhibited a 14° lower contact angle with foliage compared to commercial suspensions. The encapsulation of TEB within the polymer enhanced its resistance to photolysis, resulting in a 5‐h extension of its half‐life. TEB NPs were readily taken up by fungi and plants, thereby enhancing fungicidal efficacy. This nanopesticide could achieve the desired antifungal effect with reduced dosage and improved pesticide utilization. Therefore, the work is expected to provide a simple nanoplatform for improving pesticide utilization and promoting green agriculture. [ABSTRACT FROM AUTHOR]

Benefiting from a series of pollution prevention initiatives, fine particle (PM2.5) pollution was effectively controlled in 2018–2020, but ground-level ozone pollution during warm season has become a major issue for the continuous air quality improvement in Beijing. As a key source of hydroxyl (OH) radical, nitrous acid (HONO) has attracted much attention for its important role in the atmospheric oxidant capacity (AOC) increase; the elucidation of the pollution characteristics, unknown sources and the contribution to secondary pollution of HONO has become a research hotspot. In this study, we made a comparative study on the ambient levels, variation patterns, sources and formation pathway in warm season (from June to October in 2021) on a basis of a continuous intensive observation in an urban site of Beijing. The monthly average mixing ratio of HONO were 1.26 ppb, 1.28 ppb, 1.01 ppb, 0.96 ppb, 0.89 ppb, respectively, showing a larger contribution to OH radical relative to ozone at daytime with a mean OH production rate of 2.70, 2.91, 2.00, 2.25, and 0.93 ppb/h, respectively. The emission factor from the vehicle emissions, Pemis, was estimated to be 0.017, higher than most studies conducted in Beijing, the observation site and traffic control policies could affect this phenomenon. The homogeneous production of HONO via reaction of NO + OH, PnetOH+NO, in each month were 0.050, 0.045, 0.033, 0.052, and 0.17 ppb/h, respectively. The average nocturnal NO2 to HONO conversion frequency CHONO in each month were 0.011 h−1, 0.0096 h−1, 0.013% h−1, 0.0081 h−1, and 0.0017 h−1, respectively. In warm seasons, the missing source of HONO, Punknown, around noontimewere 0.29–2.37 ppb/hr. Punknown in each month might be various. According to the observation results, relatively low humidity and strong solar illumination were conductive to HONO formation in June, which might be due to light-induced heterogeneous reactions of NO2. In July in Beijing, high humidity condition was beneficial to the heterogeneous reaction of NO2, and due to the increase of precipitation, more HONO would enter the liquid phase (the high Henry coefficient of HONO). For days with high humidity and strong sunlight in June and August, photolysis of nitrate was also one important HONO source. For August and September, light-induced reactions of NO2 on non-aerosol surfaces under relatively low humidity and strong light conditions could be an important HONO source. In addition, the presence of Cl ions and sulfate could enhance the photolysis of nitrate, and this was obvious in July and October; the presence of organic compounds also could have this effect, which was obvious in June and October. Not only the HONO concentration but also the HONO source has temporal patterns, even within a season, it varies from month to month. This work highlights the importance of HONO for AOC in warm season, while encouraging long-term HONO observation to assess the contribution of HONO sources over time compared to the capture of pollution processes. [ABSTRACT FROM AUTHOR]

Unpredictable in vivo therapeutic feedback of reactive oxygen species (ROS) efficiency is the major bottleneck of photodynamic therapy (PDT). Herein, novel PDT‐based nanotheranostics Pa–Mn&CH‐A@P are elaborately constructed for in vivo tracking biodistribution and in situ self‐reporting PDT, which innovatively unites magnetic resonance imaging (MRI) and chemiluminescence (CL) signals. Taking advantages of the versatility of lanthanide coordination chemistry and flash nanoprecipitation (FNP) technology, photosensitizers, MRI, and CL agents are unprecedently integrated within a stable and uniform nanotheranostic. Specifically, MRI signal offers detailed dose distribution of nanotheranostics with high‐spatial resolution, and CL signal timely performs in situ evaluation of ROS generation with high sensitivity. This dual‐modal MRI/CL nanotheranostic makes a breakthrough in high fidelity feedback for oral tumor, conquering the inherent unpredictable obstacles on spatially and sensitively reporting PDT. [ABSTRACT FROM AUTHOR]