Atherosclerosis, a disease that mainly affects human blood vessels, can cause various cerebral ischaemic diseases such as coronary heart disease and peripheral arterial disease. However, conventional drugs for the treatment of atherosclerosis have the disadvantages of low bioavailability and high toxicity. Bowl-shaped particles not only have the excellent properties of traditional spherical particles, such as improved drug distribution, increased drug absorption, reduced drug toxicity and side effects, but also are easier to circulate in the blood for a long time, have reduced immune rejection and have a larger specific surface area. Chitosan/polycaprolactone bowl-shaped particles were prepared via electrostatic spraying, and the effects of precursor solution concentration and polymer ratio on particle morphology were investigated. Chitosan/polycaprolactone composite bowl-shaped particles containing hirudin were prepared under optimal parameters for sustained anticoagulation. The anticoagulant molecules of hirudin could be continuously released from the composite scaffold as the bowl particles degraded. The biocompatibility and haemocompatibility of the composite particles were assessed using mouse glial cells and rabbit blood, and the results showed that the cell viability of the drug-loaded particles was overall above 90% and the haemolysis rate was below 2%. By controlling the release rate of hirudin, bowl-shaped particles can achieve a long-term anticoagulant drug delivery system and have wider application potential as a novel blood contact material.

Amidst rapid industrialization and urbanization, air pollution has emerged as a global environmental challenge. Traditional air filtration materials face challenges in effectively filtering PM0.3 and often result in discomfort due to high air resistance when used for personal protection, as well as excessive energy consumption in industrial air purification applications. This study initially utilized extremely high environmental humidity to induce fiber formation, resulting in the preparation of a fluffy fiber membrane with a three-dimensional curly morphology, which increased the porosity to 96.93%, significantly reducing air resistance during filtration. Subsequently, rutile TiO₂ with a high dielectric constant was introduced, exploiting the low pressure drop characteristic of the fluffy 3D curly fiber membrane combined with the electret effect of TiO₂ nanoparticles to notably improve the issue of excessive pressure drops while maintaining filtration efficiency. The microstructure, morphology, and element distribution of the fibers were analyzed using FESEM and EDS. FTIR and XRD were employed to examine the functional groups and crystal structure within the fibers. The electret effect and filtration performance of the fiber membrane were investigated using an electrostatic tester and a particulate filtration efficiency tester. The results demonstrated that inducing fiber formation under high-humidity conditions could produce fibers with a 3D curly structure. The fiber membrane was highly fluffy, significantly reducing the pressure drop. Introducing an appropriate amount of titanium dioxide markedly improved the electrostatic effect of the fiber membrane, enhancing the filtration performance of the 3D curly PVDF/TiO₂ composite fiber membrane. With a 0.5% addition of TiO₂ nanoparticles, the filtration efficiency of the fiber membrane reached approximately 99.197%, with a pressure drop of about 49.83 Pa. This study offers a new approach to developing efficient, low-resistance air filtration materials, showcasing the potential of material innovation in addressing air quality challenges within the sustainable development framework.

Processing polyethylene terephthalate (PET) into functional materials has both sustainable and economic significance. Therefore, this study aims to prepare functional nanofibers using PET, combining electrospun nanofibers with metal–organic frameworks (MOFs), which is an effective solution to increase the added value of functional nanofiltration membranes (NFMs). The surface morphology of PET fibers is successfully controlled by electrospinning parameters and post-treatment. The formation of a uniform coating of CuBTC crystals on the PET surface is induced by a simple and low-cost in situ growth technique. CuBTC@PET was treated to prepare superhydrophobic CuBTC@PET (SCP), thus improving the stability of CuBTC in water and expanding its potential applications. Through a series of optical and thermal characterizations, the porous morphology formation mechanism and MOF in situ growth mechanism of SCP fibers were discussed. Then, the air filtration performance and bacteriostatic properties of SCP nanofiltration membranes were investigated. The as-prepared SCP showed a high water contact angle (146.4°), low-pressure drop (39.7 Pa), and high filtration efficiency (95.3%, 3 μm NaCl), as well as unique, broad-spectrum antibiosis potency against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). This study shows that SCP nanofiltration membranes can be practically applied in high-performance antibacterial filtration membranes.