Preparation of thermo and pH-responsive polymer@Au/Fe3O4 core/shell nanoparticles as a carrier for delivery of anticancer agent

In this work, a thermo and pH-responsive poly-N-isopropylacrylamide-co-itaconic acid containing thiol side groups were successfully synthesized to prepare Doxorubicin-loaded polymer@Au/Fe3O4 core/shell nanoparticles (DOX-NPs). Copolymer and NPs were fully characterized by FT-IR, HNMR, photo-correlation spectroscopy, SEM, X-ray diffraction, vibrating-sample magnetometer, thermal gravimetric analysis, and UV-Vis spectroscopy. The stimuli-responsive characteristics of NPs were evaluated by in vitro release study in simulated cancerous environment. The biocompatibility and cytotoxic properties of NPs and DOX-NPs are explored by MTT method. The prepared NPs with the size of 50 nm showed paramagnetic characteristics with suitable and stable dispersion at physiological medium and high loading capacity (up to 55 %) of DOX. DOX-NPs yielded a pH- and temperature-triggered release of entrapped drugs at tumor tissue environment (5 % of DOX release) compared to physiological condition (20 % of DOX release) during 48 h. In vitro cytotoxicity studies indicated that the NPs showed no cytotoxicity on A549 cells at different amounts after incubation for 72 h confirming its suitability as a drug carrier. DOX-NPs, on the other hand, caused an efficient anticancer performance as verified by MTT assay test. It was concluded that developed NPs by us in this study may open the possibilities for targeted delivery of DOX to the cancerous tissues.