Authors: S. Ghosh, T. Cai, S. GhoshMitra, A. Neogi, Z. Hu, N. Mills
Affilation: Southeast Missouri State University, United States
Pages: 708 - 710
Keywords: AC magnetic field, nano-scale heating, thermoresponsive hydrogels
Magnetically responsive thermo-active hydrogels offer several potential advantages over other bio-material systems for the controlled release of drugs and targeted thermal therapy of the cancerous cells. Thermal and magnetic responses of hydrogels can be tuned by varying the size and concentration of embedded nanoparticles and varying the magnitude and frequency of the magnetic field. In this present work, a novel polyethylene glycol (PEG) based thermo-responsive nanoscale system provides controlled heating and volumetric changes in response to an AC magnetic field. PEG is nontoxic, anti-immunogenic and FDA-approved and this innovative application has led to a fast-responsive, magnetic hydrogel system consisting of all FDA-approved bio-materials. Volumetric changes of the magnetic PEG nano-spheres were compared against widely used PNIPAM nano-spheres in the range of 20-40°C by dynamic light scattering measurements and electron microscopy. The limiting size and optimal concentration of nanoparticles facilitated the gel in maintaining its de-swelling property as unaffected. Yet actuation was possible under a comparably smaller magnetic field, thus reducing the power consumption and toxicity while enhancing gel performance. The enhanced volume shrinkage and actuation efficiency is more ideal for controlled drug release and temperature regulation for hyperthermia applications.