Advancing Photodynamic Therapy Efficiency on MCF-7 Breast Cancer Cells through Silica Nanoparticles-Safranin Encapsulation: In-Vitro Evaluation

Efficient drug delivery to target tissue is a major challenge in many cancer treatment modalities. Silica nanoparticles (SiNPs) have been identified as an ideal drug carrier due to their unique properties. In Photodynamic therapy (PDT), one of the key challenges in utilizing photosensitizers (PS) lies in effectively delivering the PS to the targeted tissue. Using Silica nanoparticles encapsulation will effectively prevent the leakage of entrapped PS from the particles, protects against reduction by the retinal endothelial system, and reduces PS toxicity. In this study, Silica nanoparticles (SiNPs) were used as carriers for Safranin (SF) as a photosensitizer agent to treat MCF-7 breast cancer cells in vitro. The SiNPs nanoparticles were synthesized, and their size and shape were measured using Transmission Electron Microscopy (TEM). Cytotoxicity was evaluated for different concentrations of encapsulated and naked SF. The optimal concentrations and exposure times required to eliminate the MCF-7 under light (Intensity ~110 mW/cm², red laser) were determined. The results indicated that encapsulated SF by SiNPs exhibited higher efficacy than naked SF with a +50% concentration efficacy and +78% exposure time efficacy. This confirmed the superior ability of encapsulated SF to eliminate MCF-7 cells compared to naked SF. The use of synthesized silica nanoparticles loaded with SF improved photodynamic therapy by increasing the bioavailability of SF in the target cells. Our results demonstrate that SiNP encapsulation significantly improves the efficacy of SF in eliminating MCF-7 cells compared to bare SF. This study underscores the potential of SiNPs as a drug delivery system for photodynamic therapy and could pave the way for developing more effective cancer treatments.