Impact of oil phase composition on the efficacy of nanoemulsions for verteporfin-mediated photodynamic therapy in ovarian cancer

Nanomedicine has emerged as a powerful strategy to enhance both therapeutic efficacy and diagnostic precision in oncology. Among the various nanoscale platforms, nanoemulsions have shown promising potential as drug delivery systems, particularly in photodynamic therapy. However, the design of effective nanoemulsions requires careful consideration of multiple formulation parameters, especially the choice of the oil core, which remains insufficiently explored. In this study, we developed and compared two nanoemulsions differing only in their oil phase, oleic acid or miglyol, both loaded with the photosensitizer verteporfin, a clinically approved photosensitizer. We systematically evaluated their physicochemical characteristics, loading capacity, encapsulation efficiency, storage stability, and therapeutic efficacy in an ovarian cancer cell line. Our results demonstrate that the oil phase significantly influences nanoemulsion performance. Verteporfin-loaded miglyol-based nanoemulsions exhibited higher drug loading capacity, improved colloidal stability, and greater photodynamic cytotoxicity compared to the oleic acid-based counterpart. These findings underscore the critical role of formulation components in determining the functionality of nanocarriers and highlight the importance of rational nanoemulsion design to maximize therapeutic outcomes in photodynamic therapy and broader nanomedicine applications.