Antibacterial Mechanisms, Functionalization Strategies, and Multi-Disciplinary Applications of Perylene Diimide.

As an organic semiconductor material with unique electronic structures and photophysical properties, perylene-3,4,9,10-tetracarboxydiimide (PDI) has recently demonstrated tremendous potential in the antibacterial field. This review systematically summarizes the structural characteristics and physicochemical properties of PDI, with a particular focus on its multi-dimensional antibacterial mechanisms, including: (i) direct interaction with bacterial membranes leading to membrane disruption, (ii) photocatalytic generation of reactive oxygen species (ROS) that induce oxidative stress in bacteria, (iii) photothermal effects that locally elevate temperature to achieve bacterial ablation, and (iv) synergistic multi-mechanistic effects that further enhance antibacterial efficiency. In addition, PDI exhibits excellent bacterial capture capability, which can further improve antibacterial performance through adsorption and enrichment. From an application perspective, PDI-based materials have shown significant progress in bacterial infection therapy, water purification, and antibacterial coatings or implants. Furthermore, the biosafety and potential risks of PDI in both in vitro and in vivo applications are discussed. Finally, this review provides a perspective on the future directions and challenges in the development of PDI-based antibacterial materials. Overall, the review aims to offer a comprehensive summary and valuable reference for understanding PDI's antibacterial mechanisms and advancing its clinical and environmental applications.