Magnetically controlled nanoparticles for paclitaxel release from polymer encapsulated iron oxide nanoparticles fabricated via flash nanoprecipitation

Magnetically controlled drug release, combining superparamagnetic iron oxide nanoparticles (IONPs), biocompatible polymers and therapeutic drugs, offers a promising alternative to conventional cancer therapies, enhancing efficacy while minimizing side effects. One approach for encapsulating organic and inorganic moieties in polymers is by using flash nanoprecipitation (FNP), a method known for its robustness and scalability. In this study, IONPs were synthesized via co-precipitation, followed by oleic acid coating to impart hydrophobicity, resulting in dry sizes of 9 ± 2 nm. These oleic acid coated IONPs (OA-IONPs) were encapsulated in poly(lactic-co-glycolic acid) (PLGA) using FNP, following operational conditions used for bare polymeric nanoparticles (PNPs). For a defined set of operational variables, it was observed that increasing the theoretical concentration of IONPs in the solvent stream from 0.11 wt% to 0.34 wt% resulted in enhancement of IONPs encapsulation efficiency. The FNP process was further modified to encapsulate a hydrophobic anti-cancer drug, paclitaxel and the co-encapsulation of IONPs and the drug was confirmed through various characterization techniques, including electron microscopy, energy dispersive X-ray and Fourier Transform Infrared spectroscopies. Magnetically controlled drug release was investigated using an alternating magnetic field, revealing that drug release was at least four times higher than the case where the magnetic field was absent. These findings along with biocompatibility studies showcase potential of such magnetically controlled drug release nanocarriers in cancer therapeutics.