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.
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.