Coordinately Tethered Iron(III) Fluorescent Nanotheranostic Polymer Ascertaining Cancer Cell Mitochondria Destined...

Magnetic resonance imaging-aided real-time diagnosis along with enhanced chemotherapeutic efficacy using a sequential receptor and mitochondria dual-targeting polymer theranostic has become a promising strategy for the effective and precise treatment of cancer. Toward the accomplishment of this goal, chlorambucil (chemotherapeutic agent), biotin (receptor targeting agent), a triphenylphosphonium segment (mitochondriotropic agent), and an iron rhodamine complex (integrated fluorescence-MR imaging agent) were tethered under a single polymer. Owing to the polymer's (RD CH PG BN TP Fe) amphiphilic character, it spontaneously self-assembled into nanospheres, which exhibited a remarkable effect on the relaxation of the water proton. Further, the qualitative estimation of the change in intensity for the water-proton signal reflected its potential as a T₁ contrast theranostic polymer. The mitochondria targeting competency of positively charged nanospheres was displayed using fluorescence microscopy in human cervical, HeLa, and breast, MCF-7, carcinoma cell lines. Furthermore, cytotoxicity experiments demonstrated the enhanced anticancer efficacy in both cancer cell lines. Therefore, effective and precise chemotherapy through sequential receptor-mitochondria targeting and integrated fluorescence-MR imaging would have attractive potential for decisive dose-determination by constantly monitoring the subject area of interest.