SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3649-0
Injectable hydrogels formed via dynamic chemical crosslinks hold great promise as drug delivery platforms due to their robust yet adaptable nature, stimuli-responsiveness, and tunable structures and properties. However, their inherently high water content poses a significant challenge for the efficient encapsulation and sustained release of hydrophobic drugs. Here, we present a novel injectable hydrogel system constructed via a strain-promoted disulfide-thiol exchange between dithiolane-functionalized polymer strands and thiolated core-shell nanoparticles (NPs) under physiological conditions. The hydrophobic core and hydrophilic shell structure of the NPs enables effective loading and protection of hydrophobic drugs, while rapid gelation occurs upon mixing the thiolated NPs with dithiolane-polymers in phosphate-buffered saline. The hydrogel shows excellent injectability, self-healing capability, in vitro biodegradability, and cytocompatibility. This hydrogel system enables sustained release of hydrophobic drugs over 32 days in aqueous media and supports sequential dual-drug release. Its redox-responsiveness under tumor-mimicking reducing conditions, enabled by the disulfide crosslinks, further facilitates controlled intracellular drug release. This multi-component platform offers a versatile strategy for designing advanced injectable hydrogels with potential applications in hydrophobic drug delivery and other biomedical fields.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025062404
To investigate the pollution characteristics and temporal variations of water-soluble ions in atmospheric fine particulate matter (PM2.5) during autumn and winter in Taiyuan City, continuous sampling and analysis were conducted using a Swiss Metrohm ion chromatograph in autumn and winter 2023. The results show that the daily mean concentration of nine water-soluble ions was 26.04 μg m−3, accounting for 52.1% of the average PM2.5 mass concentration. Ion concentrations ranked in descending order: NO3−, NH4+, SO42−, Cl−, K+, Na+, Ca2+, F−, and Mg2+. Secondary inorganic ions (SNA) constituted 87.6% of total water-soluble ions. The mass ratio of NO3− to SO42− reached 1.83, indicating a shift from sulfate-dominated to nitrate-dominated aerosol chemistry. During pollution episodes, water-soluble ion concentrations increased exponentially, with distinct ion-specific trends: on moderately polluted days, SO42− increased to 5.31 times that on clean days, whereas on heavily polluted days, NO3− increased to 5.37 times, highlighting nitrate as a primary driver of severe pollution. Comparison with historical data reveals a recent increase in the proportion of water-soluble ions in PM2.5, with higher proportions during more polluted periods. Analysis of NH4+ forms and PM2.5 acidity suggests that acidic components contribute more under heavier pollution. Positive matrix factorization (PMF) identified four major sources: secondary sources, combustion and motor vehicles, industrial sources, and dust. The secondary source contributions were 45.4%, 64.7%, and 63.4% on clean, lightly polluted, and moderate-to-heavy polluted days, respectively, indicating a significantly higher secondary contribution on polluted days.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025012501
Dibutyl phthalate (DBP) is a ubiquitous environmental pollutant posing potential risks to aquatic ecosystems. This study assessed the developmental toxicity of DBP in Japanese medaka (Oryzias latipes) embryos. Embryos were exposed to gradient DBP concentrations (1, 5, 50, 500 μg·L−1, and 5 mg·L−1) for 15 days. Endpoints included embryonic heart rate, hatching time, survival rate, larval swimming behavior, and expression of genes related to cardiovascular, nervous, thyroid, antioxidant systems, and estrogenic effects. Results showed that 5 mg·L−1 DBP significantly reduced embryonic heart rate (P < 0.0001), leading to hatching failure and mortality. Exposure to 500 μg·L−1 DBP significantly reduced hatching rate (P < 0.01) and survival rate (P < 0.0001). DBP exposure caused developmental delay, cardiovascular hemorrhage, spinal curvature, yolk sac edema, and inhibited larval swimming behavior. At the molecular level, DBP significantly altered expression of atrap, dkk1, bnpa, fx, and dvl mRNA, affecting cardiovascular development; downregulated trha, mbp, and elavl3 mRNA, indicating endocrine disruption and neurotoxicity; upregulated cat, gpx2, and gsta mRNA, inducing oxidative stress; and upregulated vtg1, erβ1, and chgl mRNA, demonstrating estrogenic effects. This study demonstrates that DBP exposure adversely affects growth, development, hatching, survival, swimming behavior, and gene expression in Japanese medaka embryos, highlighting ecological risks of DBP pollution in aquatic environments.