Synergistic therapy of magnetism-responsive hydrogel for soft tissue injuries

Soft tissue injury is very common and associated with pain, tissue swelling and even malformation if not treated on time. Treating methods include cryotherapy, electrical therapy, ultrasound therapy and anti-inflammatory drug, but none of them is completely satisfying. In this work, for a better therapeutic effect, drug therapy and pulsed electromagnetic field (PEMF) therapy were combined. We constructed a drug delivery system using the tetra-PEG/agar hydrogel (PA). By incorporating Fe3O4 NPs into the hydrogel network, a magnetism-responsive property was achieved in the system. The cytotoxicity and in vivo study showed a good biocompatibility of the PA/Fe3O4 hydrogel. A magnetism-controlled release was attained by the incorporation of Fe3O4. Finally, in vivo study showed a better performance of the DS-loaded PA/Fe3O4 compared with the commercially available DS ointment regarding the recovery of the injured soft tissue. Therefore, this magnetism-responsive hydrogel may represent a promising alternative to treat soft tissue injury.