Biomimetic helical fiber cellulose acetate/thermoplastic polyurethanes photodynamic antibacterial membrane: Synthesis, characterization, and antibacterial application

Recent advances in cellulose-based antimicrobial films: A review

Cellulose, known as the most abundant natural polymer, has renewability, good film-forming, biodegradability, safety, non-toxicity, etc. It can serve as an excellent carrier or substrate for antibacterial agents. In recent years, cellulose antibacterial membranes have become a research hotspot of new antibacterial materials. Cellulose-based antimicrobial films are extensively applied because of their impressive biocompatibility, antimicrobial performance, and other advantages. They are expected to be an effective alternative to petroleum-based antibacterial films. Therefore, the review focuses on the recent progress in cellulose-based antimicrobial films. First, the most widely used antimicrobial agents are described, along with their antibacterial mechanisms. Secondly, the latest research progress on cellulose-based antimicrobial membranes is summarized from the perspective of cellulose-based materials. The fabrication methods of cellulose-based antimicrobial films are then concluded. Finally, the recent advances in the application of cellulose-based antimicrobial film in food packaging, biomedicine, and water treatment are outlined. Moreover, the prospects are made for the study of cellulose-based antimicrobial films.

Frontiers in Bioinspired Polymer-Based Helical Nanofibers from Electrospinning

Helices are among the most significant structures in nature, representing an emerging group of materials distinguished by their unique helical geometry. Recently, helical nanofibers have attracted considerable attention due to their exceptional structural characteristics and versatile applications in various fields, including tissue engineering, biomedicine, nanotechnology, and chiral materials. Therefore, developing methods to fabricate biomimetic helical fibers on demand, which can exhibit a diverse range of physical properties and forms, is of great interest across multiple disciplines. Despite the significant interest in helical fibrous materials, the fabrication of such complex structures at the micro- or nanoscale level remains a major challenge. Electrospinning offers a simple and versatile technique for producing micro- and nanofibers in various helical shapes. This review systematically summarizes and classifies the state-of-the-art advancements in electrospun helical nanofibers into four categories based on their forming mechanisms: viscoelastic asymmetric contraction, bending instability motion, jet-induced buckling response, and rotary winding molding. Additionally, the recent applications of these helical nanofibrous materials in areas such as environmental remediation, interactive textiles, and biomedical engineering are also summarized. Furthermore, the current challenges and future perspectives in the field are put forward. We anticipate that the insights provided will contribute to the rational design of advanced artificial helical materials, thereby enhancing their practical applications in the future.

Construction of Self-Cleaning Membrane Integrating Underwater Superoleophobicity, Photocatalysis, and Antibacterial Activity for Water Purification

The treatment of oily wastewater and oil/water mixtures has received more and more attention. In this study, a Zn-MOF (ZIF-8) decorated polyimide (PI) nanofiber membrane with triple self-cleaning performance was constructed, and the decoration of ZIF-8 on the PI membrane improved the hydrophilicity of the composite membrane, which further enhanced the underwater oil resistance, and the mechanical properties of the membranes improved significantly with the increase of in situ growth time. In addition, the inherent photocatalytic and antibacterial properties of ZIF-8 endowed the membranes with fantastic performance. When the in situ growth time was 24 h, the degradation efficiency for methylene blue was nearly 90% within 60 min under visible light. The ZIF-8@PI membrane has significant antibacterial effect against Staphylococcus aureus and Escherichia coli. This triple self-cleaning is an important step forward in both the multifunctional application and sustainable development of materials.

A review of advanced helical fibers: formation mechanism, preparation, properties, and applications

As a unique structural form, helical structures have a wide range of application prospects. In the field of biology, helical structures are essential for the function of biological macromolecules such as proteins, so the study of helical structures can help to deeply understand life phenomena and develop new biotechnology. In materials science, helical structures can give rise to special physical and chemical properties, such as in the case of spiral nanotubes, helical fibers, etc., which are expected to be used in energy, environment, medical and other fields. The helical structure also has unique charm and application value in the fields of aesthetics and architecture. In addition, helical fibers have attracted a lot of attention because of their tendrils' vascular geometry and indispensable structural properties. In this paper, the development of helical fibers is briefly reviewed from the aspects of mechanism, synthesis process and application. Due to their good chemical and physical properties, helical fibers have a good application prospect in many fields. Potential problems and future opportunities for helical fibers are also presented for future studies.

Modification of traditional composite nonwovens with stable storage of light absorption transients and photodynamic antibacterial effect

Combining photodynamic antimicrobials with nonwovens is prospective. However, common photosensitizers still have drawbacks such as poor photoactivity and the inability to charge. In this study, a photodynamic and high-efficiency antimicrobial protective material was prepared by grafting bis benzophenone-structured 4,4-terephthaloyl diphthalic anhydride (TDPA) photosensitizer, and antimicrobial agent chlorogenic acid (CA) onto spunbond-meltblown-spunbond (SMS) membranes. The charging rates for ·OH and H2O2 were 6377.89 and 913.52 μg/g/h. The light absorption transients structural storage remained above 69% for 1 month. High electrical capacity remained after seven cycles indicating its rechargeability and recyclability. The SMS/TDPA/CA membrane has excellent bactericidal performance when under illumination or lightless conditions, and the bactericidal efficiency of Escherichia coli and Staphylococcus aureus reached over 99%. The construction of self-disinfection textiles based on the photodynamic strategies proposed in this paper is constructive for expanding and promoting the application of textile materials in the medical field.

Antimicrobial Photodynamic Therapy: Self-Disinfecting Surfaces for Controlling Microbial Infections

Microbial infections caused by bacteria, viruses, and fungi pose significant global health threats in diverse environments. While conventional disinfection methods are effective, their reliance on frequent chemical applications raises concerns about resistance and environmental impact. Photodynamic self-disinfecting surfaces have emerged as a promising alternative. These surfaces incorporate photosensitizers that, when exposed to light, produce reactive oxygen species to target and eliminate microbial pathogens. This review explores the concept and mechanism of photodynamic self-disinfecting surfaces, highlighting the variety and characteristics of photosensitizers integrated into surfaces and the range of light sources used across different applications. It also highlights the effectiveness of these surfaces against a broad spectrum of pathogens, including bacteria, viruses, and fungi, while also discussing their potential for providing continuous antimicrobial protection without frequent reapplication. Additionally, the review addresses both the advantages and limitations associated with photodynamic self-disinfecting surfaces and concludes with future perspectives on advancing this technology to meet ongoing challenges in infection control.