Microwave-triggered ionic liquid hydrogel for hyperthermia and transdermal antibacterial delivery

Abstract

Phototherapy still lacks effectiveness in treating tissue infections due to poor penetration depth of light and laser-induced non-specific thermal diffusion. Microwave thermal therapy (MWTT) is advantageous as characterized by strong tissue penetration, and higher heating rate. In addition, transdermal delivery of drugs helps in the treatment of tissue infections. Herein, we present an all-in-one MW-therapeutic hydrogel for eradicating bacterial infections with transdermal drug delivery. A microwave-responsive ionic liquid (IL), i.e., vinylbenzyl trimethylammonium chloride (VBTMACl), and a transdermal-enhancer IL, i.e., [2-(methacryloyloxy)ethyl] trimethylammonium chloride (ChMACl), are copolymerized with acrylic acid (AA) to form the hydrogel VACPHs. Polyvinylpyrrolidone (PVP) is incorporated with VACPHs to improve their mechanical stability. The model drug levofloxacin (LEVO) is subsequently loaded into the hydrogel, and the VACPHs-LEVO shows strong antibacterial effect. It is attributed to the efficient microwaveocaloric therapy of VBTMACl and enhanced transdermal antibiotic delivery by ChMACl. The drug delivery hydrogel developed in this research exhibits excellent performance for the treatment of deep tissue infections.