Chondroitin sulfate-capped super-paramagnetic iron oxide nanoparticles as potential carriers of doxorubicin hydrochloride

• A facile, one-pot green synthesis method was used.
• Chondroitin sulfate (CS) was an efficient capping agent for synthesis of SPIONs.
• CS interacted with iron oxide via bidentate chelation.
• DOX was entrapped onto the nanocarriers by electrostatic interaction with CS.
• IC50 value was decreased for DOX-loaded SPIONs than plain DOX.

Chondroitin-4-sulfate (CS), a glycosaminoglycan, was used to prepare CS-capped super-paramagnetic iron oxide nanoparticles, which were further employed for loading a water-soluble chemotherapeutic agent (doxorubicin hydrochloride, DOX). CS-capped SPIONs have potential biomedical application in cancer targeting. The optimized formulation had a hydrodynamic size of 91.2 ± 0.8 nm (PDI; 0.228 ± 0.004) and zeta potential of −49.1 ± 1.66 mV. DOX was loaded onto the formulation up to 2% (w/w) by physical interaction with CS. TEM showed nano-sized particles having a core-shell structure. XRD confirmed crystal phase of iron oxide. FT-IR conceived the interaction of iron oxide with CS as bidentate chelation and also confirmed DOX loading. Vibration sample magnetometry confirmed super-paramagnetic nature of nanoparticles, with saturation magnetization of 0.238 emu g−1. In vitro release profile at pH 7.4 showed that 96.67% of DOX was released within 24 h (first order kinetics). MTT assay in MCF7 cells showed significantly higher (p < 0.0001) cytotoxicity for DOX in SPIONs than DOX solution (IC50 values 6.294 ± 0.4169 and 11.316 ± 0.1102 μg mL−1, respectively).