mPEG-functionalized polyadipate triblock copolymers as promising nanocarriers for the controlled delivery of therapeutic agents in breast cancer treatment.

The increasing incidence of breast cancer is leading researchers to investigate new treatment approaches. Targeted therapy approaches are particularly attractive because they minimize the detrimental effects of therapeutic agents on healthy tissues and cells by focusing on tumor sites. This study focuses on synthesizing mPEG-modified triblock copolymers as carrier materials for drug delivery applications, enabling the efficient encapsulation of DOX, and evaluating the cytotoxic effects of the resulting nanocarriers on breast cancer cell lines. In this study, mPEG-poly(butylene adipate)-mPEG and mPEG-poly(ethylene adipate)-mPEG triblock copolymers were synthesized by a step-growth polycondensation polymerization method. Firstly, poly(butylene adipate) (pBAd) and poly(ethylene adipate) (pEAd) were synthesized to form the body of the triblock copolymer, and their chemical structures were characterized using Fourier transform infrared (FT-IR) and 1H NMR spectroscopy. The end-group analysis method was applied to determine the average molecular weights of the pBAd and pEAd polymers before their modification with mPEG-500. The nanocarriers produced by the double emulsion method were analyzed using the dynamic light scattering (DLS) method, while encapsulation efficiency and the DOX release profile were measured using a spectrofluorometer. The antiproliferative effects and cellular uptake capacities of the resulting nanocarriers were subsequently examined in MCF-7 and MDA-MB-231 cells. The cytotoxicity of DBANP and DEANP nanocarriers was lower than that of free DOX, demonstrating that encapsulation reduces drug-associated toxicity and may enhance safety. These findings suggest that the nanocarrier systems developed in this study show strong potential as promising candidates for breast cancer therapy.