Abstract
Cancer is a prevalent disease worldwide. Photodynamic therapy (PDT) is a non-invasive and highly targeted treatment for certain types of cancer. Recently, it has been combined with nanotechnology, e.g., nanogel, for enhancing its therapeutic efficacy. "Curcumin" is a more typical naturally occurring photosensitizer (PS) in PDT, due to its wide range of pharmacological activities, including anticancer, anti-inflammatory, antibacterial, and antiviral effects. However, curcumin has low bioavailability, limiting its therapeutic potential, which can be improved with the help of nanotechnology. Growing evidence has shown that curcumin-loaded nanogels have their specific functions, such as drug delivery and cancer targeting. Curcumin-loaded nanogel has overcome the limitations of free curcumin, such as solubility and controlled release, with the help of these, as they provide a multifunctional platform to enhance the therapeutic effects of PDT. However, it is still required to further investigate the combinations of curcumin, nanogel, and PDT. Much more work needs to be done, including safety assessments of curcumin-loaded nanogel with PDT delivery systems, long-term toxicity on the human body, and optimization of dosage for curcumin, nanogels, PS, light parameters, and delivery mechanisms for the PDT process, as well as the exploration of tumor-specific targeting and immune response for humans, for example, adverse drug reactions or drug to herbal interaction.