Abstract
Photodynamic therapy (PDT) has emerged as a clinically approved, non-invasive cancer treatment that induces tumor cell death through the intracellular generation of reactive oxygen species (ROS) upon exposure to non-ionizing radiation. Its effectiveness relies on the synergistic action of a photosensitizer (PS), light, and molecular oxygen, with the therapeutic response shaped by the PS's selective accumulation in tumor-associated organelles such as mitochondria and lysosomes. Despite its clinical utility, conventional PDT faces significant challenges, including limited specificity, poor bioavailability. To address these limitations, recent advances in nanotechnology, particularly liposomal drug delivery systems, have demonstrated significant potential in enhancing the efficiency and selectivity of PDT. Liposomes, with their amphiphilic nature and biocompatibility, enable controlled PS release, enhanced tumor targeting, and reduced systemic toxicity. Furthermore, functionalization with ligands and integration of imaging agents have led to the development of multifunctional liposomal nanocarriers capable of simultaneous therapy and diagnosis (theranostics). This review discusses the evolving trends in liposome-based nanomedicine for PDT, including the incorporation of green nanotechnology approaches that utilize biologically derived agents to synthesize eco-friendly nanoparticles with improved photochemical performance. The review also emphasizes the role of surface modification strategies to boost cancer cell specificity, highlighting recent developments aimed at improving the clinical translation of liposome-based PDT systems for more precise and effective cancer treatment.