Although various methods are used today in the diagnosis and treatment of breast cancer, traditional approaches have disadvantages such as drug resistance, drug cytotoxicity, metastasis, and relapse. Therefore, new methods need to be developed for early diagnosis of the disease and improvement of the treatment process. Photodynamic diagnosis and therapy have gained importance in this context in recent years. The primary purpose of this study was to use metal-organic frameworks for the first time to include methylene blue in the breast cancer treatment process with photodynamic therapy. The nano-delivery system using methylene blue was examined for its cytotoxic effect on breast cancer cell lines MDA-MB-231 and MCF-7. Since ZIF-8 degrades and provides zinc to cells, this material was expected to have an additional therapeutic property alongside photodynamic therapy. In addition, the combination of multiple cytotoxic components in a single nanoparticle and their combined effects was evaluated. The new generation nanocarriers were designed to release methylene blue specifically in cancer cells with low pH, avoiding damage to healthy tissues and enhancing the quality of the treatment process.