Rod-Like PLGA Microrobots with Enhanced Motion and Biodegradation for Magnetic-Guided Drug Delivery

Poly (lactic -co -glycolic acid) (PLGA) is a promising material for creating microrobots for drug delivery due to their biodegradability, biocompatibility, and FDA approval for clinical use. Nevertheless, traditional spherical PLGA drug carriers continue to face challenges, including limited motion efficiency and slow degradation. This study introduces rod-like Fe 3 O 4 @PLGA microrobots fabricated via a low-cost, scalable stretching method, to address these limitations. Their rod-like structures enhance their motion efficiency under rotating magnetic fields, outperforming their spherical counterparts by ≈58%. Thermogravimetric, Fourier transform infrared, and magnetization analyses confirm their excellent structural integrity and ample magnetic content of 39.8%. In vitro biocompatibility tests reveal no significant cytotoxicity toward L929 and HeLa cells. Their rod-like structures exhibit accelerated degradation, with swelling size 1.59 times higher than spheres by day 40, enabling rapid drug release with a 40.2% improvement. Fluorescence imaging validates uniform doxorubicin encapsulation and retention post-deformation. These results demonstrate that rod-like PLGA microrobots synergize precise magnetic navigation, high drug-loading capacity, and tunable degradation, offering a transformative platform for targeted therapies, particularly in acute conditions like localized cancer intervention.