The outcome of cancer treatment has progressed impressively in recent years. This is largely due to development of precision medicine strategies tailoring genetic analysis to individualized treatment options by means of targeted drug delivery or drugs targeting the hallmarks of cancer. Outcome of photodynamic therapy (PDT) is expected to benefit from targeted delivery of the photosensitizers by means of e.g. antibodies and nanoconstructs as a supplement to the focused laser-based light delivery. Additionally, to further improve outcome of PDT combination with one or more treatment modalities has also attracted much attention. The aim of this topical collection is to provide a comprehensive platform of reviews, perspective, original papers, communications and technical notes on PDT in combination with other treatment modalities and/or drug delivery technologies.

The growing challenge of microbial resistance to conventional treatments has fueled the search for innovative, effective, and versatile therapeutic alternatives, especially as the need for alternative therapies that bypass traditional resistance mechanisms is urgent. Antimicrobial Photodynamic Therapy (aPDT) has emerged as a promising solution - offering not only a novel mechanism of action but also a unique platform for targeted delivery of therapeutic agents, with a wide range of potential applications - in human and veterinary medicine, agriculture, surface and environmental disinfection. Aiming to highlight the research teams working on a more efficient and controlled delivery of light and / or photosensitizers, PPS publishes this Topical Collection, under the title “Delivering light and molecules to pathogens: rising strategies on Antimicrobial PDT”, providing an scenario for original research and literature reviews, and contributing to the advancement and evolution of this technique. This topical collection explores the cutting edge of aPDT, with a particular focus on the dual delivery systems crucial to its success: photosensitizers (PS) and light. We invite contributions that advance our understanding and application of delivery strategies in aPDT, encompassing both PS formulations and sophisticated light-delivery methodologies. Importantly, this collection aims to challenge the oversimplification often seen in light delivery approaches. Precision in light application is just as critical as PS optimization, especially when moving beyond the laboratory bench. Contributions that present novel materials, delivery vectors, mechanisms, or application techniques - either separately or in combination - are especially welcome. By bringing together interdisciplinary research on light and molecular delivery in aPDT, this collection seeks to redefine how we approach infectious disease treatment in the era of antibiotic resistance.