Biomimetic Fibrous Leaf-Vein Membrane Enabling Unidirectional Water Penetration and Effective Antibacterial PM Filtration

Abstract

Air pollution induced by pathogenic particulate matter (PM) has posed a serious threat to public health worldwide. Advanced air filters are thus required, not only exhibiting high PM capture efficiency, low breathing resistance, and high internal moisture transferring performance but also isolating and inactivating external pathogenic aerosols. In this study, we demonstrated a facile approach to construct a biomimetic fibrous leaf-vein membrane with unidirectional water penetration and effective antibacterial PM filtration by one-step electrospinning of poly­(vinylidene fluoride) (PVDF)-based multilayer nanofibers. With ultrathin fibers penetrating the skeletal framework of bimodal thick fibers, the membranes showed gradient interconnected porous structures and achieved a highly efficient and stable (in an acid and alkali environment) PM0.3 interception (>99.98%) with low air drag (51–71 Pa). In addition, the gradient narrow pores of the membranes contributed to a gradient higher hydrophilicity. The subsequent unidirectional water motion effectively isolates pathogenic aerosols typically generated by external individuals or ultrafast water penetration from the inverse face. Moreover, the membranes demonstrated an antibacterial efficacy (>99.99%) in a 5 min contact, inactivating the intercepted airborne pathogens efficiently. The test results proved that the proposed membranes were promising advanced air filters for respirator applications.

Durable and Nontoxic Natural Rubber-Based Composites with Antibacterial Properties

“…This enhanced the binding force between the whiskers and the rubber matrix. The mechanical properties of the NDZ101–CaCOw/NR composites and NDZ101–MOSw/NR composites were superior to those of pure NR …”

“…The absorbance value (OD) at 450 nm was measured using a microplate reader after incubating the plates for 2 h without light. (2) The cytocompatibilities of pure NR and NDZ101-whiskers/NR were confirmed via live/dead fluorescent staining: an AM/PI staining kit and a culture medium were prepared accordingly in the volume ratio of 1:1000; the reaction solution was added to the 96-well plates and incubated for 20 min; photographs of the plates were captured with a fluorescence microscope …”

Preparation of fluffy bimodal conjugated electrospun poly(lactic acid) air filters with low pressure drop

“…Long-term exposure to air pollution and particulate matter (PM) can cause individuals to develop pneumoconiosis and other diseases. 1,2 Small airborne particles, such as PM 2.5 and PM 0.3 (with a diameter of less than 2.5 mm and 0.3 mm), can bypass the body's defenses and enter our respiratory and circulatory systems. This can result in damage to our lungs, heart, and brain, making it crucial to address air pollution to safeguard public health.…”

Structural design of single functional jersey with moisture comfort based on yarn combination

“…In other words, the principle is mainly to achieve the maximum flux transport of water through the multistage bifurcation structure. 19,20 In this work, we provide a novel method of moisture conduction fabric, which is a structural design based on the fabric with a special yarn configuration, to achieve the above goals. We knitted the 75 dtex/288 f yarn and 50 dtex/14 f yarn together into a fabric.…”

“…In other words, the principle is mainly to achieve the maximum flux transport of water through the multistage bifurcation structure. 19,20…”