Zwitterionic Polysulfamide Drug Nanogels with Microwave Augmented Tumor Accumulation and On-Demand Drug Release for Enhanced Cancer Therapy

Zwitterionic polymers demonstrate as a class of antifouling materials with long blood circulation in living subjects. Despite extensive research on their antifouling abilities, the responsive zwitterionic polymers that can change their properties by mild outside signals are poorly explored. Herein, a sulfamide-based zwitterionic monomer is developed and used to synthesize a series of polysulfamide-based (poly (2-((2-(methacryloyloxy)ethyl) dimethylammonio)acetyl) (phenylsulfonyl) amide (PMEDAPA)) nanogels as drug carriers for effective cancer therapy. PMEDAPA nanogels are proved to exhibit prolonged blood circulation without inducing the accelerated blood clearance phenomenon. Intriguingly, PMEDAPA nanogels can sensitively respond to hyperthermia by adjusting the crosslinker degree. After modified with transferrin (Tf), the nanogels (PMEDAPA-Tf) achieve shielded tumor targeting at normothermia, while exhibiting recovered tumor targeting at hyperthermia, leading to enhanced tumor accumulation. Meanwhile, PMEDAPA-Tf nanogels show superior penetration ability in 3D tumor spheroids and faster drug release at hyperthermia compared with that at normothermia. In combination with mild microwave heating (approximate to 41 degrees C), the drug-loaded PMEDAPA-Tf nanogels show a pronounced tumor inhibition effect in a humanized orthotropic liver cancer model. Therefore, the study provides a novel hyperthermia-responsive zwitterionic nanogel that can achieve augmented tumor accumulation and on-demand drug release assisted with clinically used microwave heating for cancer therapy.