Construction of pH-responsive albumin nanoparticles loaded with baicalin and evaluation of their anti-breast cancer activity.

Breast cancer (BC) stands as one of the primary malignancies threatening women's health. Baicalin (BA) exhibits anti - BC effects, yet it is plagued by issues such as low water solubility and poor bioavailability. To enhance the anti-BC efficacy of BA, this study developed a pH - responsive albumin nanoparticle loaded with BA (BA-AN-FA@mPEG). The optimized BA-AN-FA@mPEG features an average particle size of (185.8 ± 2.36) nm, a Zeta potential of (-32.70 ± 1.27) mV, an encapsulation efficiency of approximately 73.82 %, and a drug loading of about 5.68 %. The aqueous solution of BA-AN-FA@mPEG demonstrates excellent stability at 4 °C, with no significant drug leakage occurring within 12 weeks. BA-AN-FA@mPEG shows a certain sustained - release effect, and the drug release rate is faster under acidic conditions. The results of efficacy evaluation indicate that the half - maximal inhibitory concentration of BA-AN-FA@mPEG against MDA-MB-231 cells is 26.34 μg/mL. It can promote cellular uptake, effectively induce apoptosis, and cause cell cycle arrest. In summary, BA-AN-FA@mPEG is a promising tumor - targeted therapeutic formulation that can improve drug stability, tumor delivery efficiency, and therapeutic efficacy.