Fabad Journal of Pharmaceutical Sciences, cilt.50, sa.3, ss.621-634, 2025 (Scopus, TRDizin)
Letrozole (LTZ) is a first-line aromatase inhibitor for hormone-sensitive breast cancer in postmenopausal women, but its poor aqueous solubility and limited tissue selectivity reduce therapeutic efficacy. This study aimed to develop liposome and chitosan-coated liposome (chitosome) formulations as lipid-chitosan-based nanocarriers to enhance LTZ delivery, enable sustained release, and minimize side effects. LTZ-loaded liposomes were prepared by the thin-film hydration method, and the optimal formulation was selected for chitosan coating. The impact of chitosan on physicochemical properties was assessed through particle size, zeta potential, encapsulation efficiency, and stability studies. In vitro drug release was evaluated via dialysis at 37°C, and cytotoxicity was tested on MCF-7 breast cancer cells. Optimized liposomes and chitosomes exhibited mean particle sizes of 112 nm and 155 nm, respectively, with high encapsulation efficiency (>90%). Chitosan coating led to a slight reduction in the net negative zeta potential, decreasing it from -48.9 mV to -40.0 mV. Both formulations demonstrated sustained LTZ release and maintained their particle size stability after one month of storage at 2–8°C (p>0.05). Cytotoxicity assays indicated that both formulations exhibited similar effects to free LTZ on MCF-7 cells. In conclusion, LTZ-loaded liposome and chitosome formulations were successfully developed, offering a favorable particle size, high encapsulation efficiency, and sustained drug release. Chitosan coating modified surface properties and influenced formulation stability. These findings suggest that lipid-chitosan nanocarriers are promising platforms for LTZ delivery. Further in vivo studies are warranted to confirm their potential in breast cancer therapy.