Photoactive Dye‐Loaded Polymer Materials: A New Cutting Edge for Antibacterial Photodynamic Therapy

Abstract Healthcare‐associated infections remain a significant health concern, particularly with the emergence of antibiotic resistance. While these antibiotics have saved countless lives, their overuse reduces their efficacy promoting the emergence of multidrug‐resistant (MDR) bacteria. This prompts researchers to explore new alternatives for treating bacteria proliferation. In this context, antibacterial photodynamic therapy (aPDT) has emerged as a promising approach for treating localized infections. It utilizes reactive oxygen species (ROS) as oxidative stress agents, thereby minimizing the risk of developing MDR. The success of aPDT significantly hinges on the careful selection of photosensitizers (PSs) and polymer matrices for the synthesis of polymer‐based photoactive materials. Various light‐absorbing PSs are therefore designed for enhancing ROS production and antimicrobial efficacy. By incorporating PSs into polymer matrices, these materials can harness the light power to generate ROS, destroying bacterial cells upon irradiation. This review aims to provide a comprehensive overview of advancements in this field, specifically focusing on the use of polymer‐based materials. The mechanism of the four main ROS generated in aPDT, the methods used for their detection, and their mode of action against bacteria has been outlined. The recent improvement in polymer‐based aPDT materials and their antibacterial efficacy have been also addressed.