Evaluation of curcumin (CUR) loaded BSA nanoparticles for <i>in-vitro</i> photodynamic therapy on MCF-7 cell line

Curcumin (CUR) is a natural phenolic compound with potent anticancer properties and potential as a photosensitizer (PS) for photodynamic therapy (PDT). However, its clinical application is limited by poor solubility, low bioavailability, and rapid degradation. To address these challenges, this study introduces curcumin-loaded bovine serum albumin nanoparticles (CUR-BSA NPs) as a pH-responsive drug delivery system for enhanced PDT in breast cancer treatment. CUR-BSA NPs were synthesized using the desolvation method and characterized by using Field emission scanning electron microscopy (FESEM), Dynamic light scattering (DLS), Fourier-transform infrared (FT-IR) spectroscopy. The nanoparticles with size (∼170 nm), zeta potential (−36 ± 2.7 mV), and encapsulation efficiency (47.5%), demonstrated pH-responsive drug release, with higher curcumin release under acidic conditions, mimicking the tumor microenvironment. <i>In-vitro</i> cytotoxicity studies on MCF-7 breast cancer cells revealed that CUR-BSA NPs, in combination with blue light irradiation (420 nm, 30 J/cm²), significantly reduced cell viability to 69% after 48 h, while CUR-BSA NPs show lower cytotoxicity (45% vs. 68%) in the absence of photodynamic therapy. TUNEL assay confirmed apoptosis in 52.4% of treated cells, compared to 4.6% in the control group. Furthermore, CUR-BSA NPs displayed excellent biocompatibility in the absence of light exposure, reducing systemic toxicity. These findings establish CUR-BSA NPs as a promising nanoplatform for PDT, providing enhanced drug delivery, tumor-targeted release, and improved therapeutic efficacy in breast cancer treatment.