In vitro and in vivo anti-tumor extrapolation of one pot engineered stimuli-responsive poly(ethylenimine) and (phenylthio) acetic acid ion pair micelles for smart delivery of doxorubicin and indocyanine green

Here, an ionic pair self-assembled micellar nanoparticles (similar to 130 nm diameter) are constructed using poly(ethylenimine) (PEI) and (phenylthio) acetic acid (PTA) for dual temperature- and oxidation (i.e., ROS)-responsive release of drugs. Further, Doxorubicin (DOX) and indocyanine green (ICG) were loaded in the micelles for synergistic chemo-phototherapy. The H-1 NMR and FT-IR spectrum of near-infrared (NIR)-treated micelles showed the oxidation of the sulfide group of PTA into the sulfone group, leading to the disassembly of the micelles and the release of payloads. The ICG loaded in PEI/PTA micelles enhanced ROS generation and increased temperature than free ICG. The In vitro and in vivo studies showed that NIR-treated DOX/ICG-loaded micelles showed a more effective reduction in tumor volume than free DOX, free DOX/ICG-loaded micelles, and DOX-loaded micelles at a similar dose. This is due to the NIR-mediated increase in ROS and temperature that results in the disassembly of micelles and the release of drugs. The TEM images of the excised tumors indicated cellular apoptosis. The in vivo imaging system showed increased uptake of ICG in the tumors of ICG micellestreated mice compared to the free ICG group. Thus, these ion-pair nanocarriers showed synergistic chemophototherapy, putting forward a therapeutic strategy to combat cancer disease.