Targeted Chemotherapy of Human Breast Cancer Cells Using Docetaxel-Loaded Nanodroplets Coated with Bovine Serum Albumin and Functionalized with Trastuzumab.

INTRODUCTION/OBJECTIVE: Breast cancer is the leading cause of cancer-related mortality among women worldwide, highlighting the need for more effective and targeted therapies. This study aimed to investigate the effects of trastuzumab-functionalized docetaxelloaded bovine serum albumin nanodroplets (TRA-DTX-BSA-NDs) on targeted therapy of Human Epidermal Growth Factor Receptor 2 (HER2)-positive breast cancer cells. METHODS: TRA-DTX-BSA-NDs were synthesized and characterized for size, morphology, zeta potential, drug entrapment efficiency, and stability. Drug release profiles were assessed under passive conditions and with ultrasound stimulation. In vitro evaluations included biocompatibility testing of SK-BR-3 (cancer) and MCF-10A (normal) cells, cellular uptake analysis, colony formation assays, and apoptosis assays. Ultrasound imaging assessed the echogenic properties of nanodroplets. RESULTS: TRA-DTX-BSA-NDs exhibited a size of 90 ± 5 nm, a zeta potential of +23.4 ± 0.4 mV, and an 84 ± 5% entrapment efficiency. Stability studies showed minimal drug leakage over 90 days. Sustained drug release was observed over 120 hours, with significantly accelerated release upon ultrasound exposure. The nanodroplets showed intense echogenicity. Furthermore, enhanced cellular uptake and selective cytotoxicity toward SK-BR-3 cells were observed. Combination treatment with ultrasound significantly reduced cancer cell viability and colony formation and increased apoptosis. DISCUSSION: TRA-DTX-BSA-NDs represent a dual-function platform for targeted therapy and imaging in HER2-positive breast cancer. The findings align with current research in nanomedicine and highlight the advantages of ultrasound-triggered delivery. Limitations include the need for in vivo studies and long-term safety evaluation. CONCLUSION: TRA-DTX-BSA-NDs show promise as an in vitro platform for targeted, ultrasound-enhanced chemotherapy, supporting further research into their use for controlled drug-delivery applications.