Synthesis of dual-responsive Janus nanovehicle via PNIPAm modified SPIONs deposition on crosslinked chitosan microparticles and decrosslinking process in the core

In this study, we developed a novel method to fabricate Janus nanoparticles with asymmetric surface chemistry through masking method in three steps which included the covalent deposition of modified magnetic iron oxide nanoparticles on the crosslinked substrate, modification of unprotected site with P(NIPAm-co-NMA) and then removing of the crosslinkages of the substrate. In continuum, the mixed nanoparticles with homogeneous surface chemistry were prepared through one-pot reaction of modified iron oxide nanoparticles with chitosan and P(NIPAm-co-NMA). In this process, the two types of polymers were simultaneously reacted with the surface of modified iron oxide nanoparticles. Both nanoparticles were reacted with Doxorubicin via imine reaction. The in vitro release was performed at two temperatures (37 and 40 degrees C) and pH values (5.8 and 7.4). Results of the comparison between the two formulations revealed that the Janus nanoparticles provided the more controllable release rather than the mixed ones. In addition, rat C6 glioma cells and OLN-93 cells were used to evaluate the cell cytotoxicity at 37 degrees C, the results demonstrated that Dox-loaded Janus nanoparticles had the desirable performance in inhibition of cancerous cells while they had less toxicity for normal cells rather in comparison to the Dox-loaded mixed ones.