Synthesis, Characterization, and Biological Evaluation of the Polymeric Encapsulation of a Ruthenium(II) Polypyridine Complex with Pluronic F-127/Poloxamer-407 for Photodynamic Therapy Applications

The therapy of cancer remains a major challenge for modern medicine. Complementary to classical treatments, the use of photodynamic therapy (PDT) has received increasing attention over the last decades. Among the classes of PDT photosensitizers (PSs) investigated, Ru(II)polypyridine complexes are currently considered as a valuable option. To improve the water solubility of these lipophilic compounds and generate a drug delivery system, these complexes can be encapsulated with polymers. Herein, the physical encapsulation of the photoactive [Ru((E,E')-4,4'-bis[p-methoxystyryl]-2,2'-bipyridine)(3)][PF6](2)complex with the polymer Pluronic F-127/Poloxamer-407 is presented. The resulting spherical particles were found to have a toxic effect in the micromolar range in human cervical carcinoma cells upon light irradiation (500 nm).