Synthesis and characterization of redox and ultrasonic dual-responsive organic-inorganic amphiphilic hybrid copolymers for drug delivery

Abstract

Redox and ultrasonic responsive copolymers MPEG-S-S-P(αN₃CL-g-ibu₇POSS)_x-r-PCL_y bearing grafted hydrophobic polyhedral oligomeric silsesquioxane (POSS) were synthesized through a click reaction between MPEG-S-S-P(αN₃CL)_x-r-PCL_y and alkynyl POSS. The morphology revealed that the copolymers underwent micellization or dissociation transitions in response to the reducing agent and ultrasound treatment. The release rate could be substantially increased and adjusted remotely under ultrasound radiation in the presence of dithiothreitol. The nanoparticles exhibited slight toxicity against HeLa cells. After high-intensity focused ultrasound (HIFU) irradiation, DOX-loaded micelles effectively inhibited the proliferation of HeLa cells with a half-maximal inhibitory concentration of 1.1 μg mL⁻¹, and enhanced cellular uptake.

Graphical Abstract

Keywords:

• Drug delivery
• micelle
• organic–inorganic hybrid
• POSS
• responsive materials

Acknowledgements

The authors thank the Microscopy Center at Chang Gung University for technical assistance. The manuscript was edited by Wallace Academic Editing.

Additional information

Funding

The research was supported by grants from Ministry of Science and Technology [MOST107-2221-E-182-015] and Chang Gung Memorial Hospital [CMRPD5H0011].