Plant-derived paclitaxel-loaded ultra-small Fe₃O₄ nanoparticles for MR imaging-mediated antitumor therapy
Xixi Lai, Yili Zhao, Zhiyuan Shi, Lingxi Xing, Xin Li, Jia Liang, Kuailu Lin
Abstract
Precise tumor imaging and effective drug delivery remain significant challenges in cancer therapy. To address these challenges, a novel drug delivery system, Us-Fe NPs/PLA-PEG@PTX, was developed for combined MR imaging and anti-tumor therapy. Ultra-small Fe 3 O 4 nanoparticles (Us-Fe NPs) were stabilized with citrate and modified with polylactic acid-polyethylene glycol (PLA-PEG) polymers to enhance biocompatibility and facilitate paclitaxel (PTX) incorporation. PTX was initially extracted from the bark of the Pacific yew tree. The system achieved an encapsulation efficiency of 72.3 % and a loading content of 6.74 %. PTX was released in a controlled manner at both neutral (pH 7.4) and mildly acidic (pH 5.5) conditions. MR imaging studies indicated potential for T1-weighted imaging. Us-Fe NPs/PLA-PEG@PTX demonstrated dose-dependent cytotoxicity (IC 50 = 0.06 μg/mL) against MDA-MB-231 cells. PEG modification reduced cellular uptake. Flow cytometry showed G2/M phase arrest and apoptosis induction, and confocal microscopy revealed microtubule disruption. These results suggest that Us-Fe NPs/PLA-PEG@PTX is a promising nano-platform for MR imaging-guided anti-tumor therapy. • Us-Fe NPs/PLA-PEG@PTX enables MR imaging with ultra-small Fe₃O₄ core. • Us-Fe NPs/PLA-PEG@PTX achieves 72.3 % paclitaxel encapsulation. • Us-Fe NPs/PLA-PEG@PTX shows dose-dependent cytotoxicity.