Trifunctional Fe 3 O 4 /CaP/Alginate Core-Shell-Corona Nanoparticles for Magnetically Guided, pH-Responsive, and Chemically Targeted Chemotherapy.

Chemotherapy of bladder cancer has limited efficacy because of the short retention time of drugs in the bladder during therapy. In this research, nanoparticles (NPs) with a new core/shell/corona nanostructure have been synthesized, consisting of iron oxide (Fe ₃ O ₄ ) as the core to providing magnetic properties, drug (doxorubicin) loaded calcium phosphate (CaP) as the shell for pH-responsive release, and arginylglycylaspartic acid (RGD)-containing peptide functionalized alginate as the corona for cell targeting (with the composite denoted as RGD-Fe ₃ O ₄ /CaP/Alg NPs). We have optimized the reaction conditions to obtain RGD-Fe ₃ O ₄ /CaP/Alg NPs with high biocompatibility and suitable particle size, surface functionality, and drug loading/release behavior. The results indicate that the RGD-Fe ₃ O ₄ /CaP/Alg NPs exhibit enhanced chemotherapy efficacy toward T24 bladder cancer cells, owing to successful magnetic guidance, pH-responsive release, and improved cellular uptake, which give these NPs great potential as therapeutic agents for future in vivo drug delivery systems.