Stimuli-sensitive fatty acid-based microparticles for the treatment of lung cancer

Abstract Despite recent advancements in medicine, lung cancer still lacks an effective therapy. In the present study we have decided to combine superparamagnetic iron oxide nanoparticles (SPION) with solid lipid microparticles to develop novel, stimuli-sensitive drug carriers that increase the bioavailability of the anticancer drug (paclitaxel — PAX) through guided accumulation directly at the tumour site and controlled drug delivery. SPION and PAX-loaded microparticles (MPs) were fabricated from lauric acid (LAU) and a mixture of myristic and palmitic acids (MYR/PAL) using hot oil-in-water emulsification method. MP size, surface properties, melting temperature and magnetic mobility were evaluated along with their in vitro efficacy against malignant lung epithelial cells (A549). MPs were spherical in shape with the average particle size between 2 and 3.5 μm and responded to external magnetic field up to the distance of 15 mm. MP were effectively internalised by the cells. Unloaded or NP-loaded MP were cytocompatible with A549 cells, while NP + PAX-loaded MP significantly decreased cell viability and effectively suppressed colony formation. The developed stimuli-sensitive, inhalable MP has shown promising results as PAX carriers for controlled pulmonary delivery for the treatment of lung cancer.