Prussian Blue Nanozyme with Multienzyme Activity Reduces Colitis in Mice

The overproduction of reactive oxygen species (ROS) is central to the progression of inflammatory bowel disease (IBD), which may be the potential therapeutic target. Prussian blue (PB) nanoparticles with good biosafety can act as an artificial nanozyme, effectively scavenging ROS. To date, PB-based nanomaterials have not been developed and utilized for treatment of IBD. In this study, poly­(vinylpyrrolidone)-modified Prussian blue (PPB) nanoparticles are constructed with good physiological stability and biosafety by a simple and efficient method. The prepared PPBs with capabilities of scavenging ROS and inhibiting proinflammatory cytokine significantly reduce colitis in mice without distinct side effects via intravenous administration. This report provides a demonstration of the protective effect of PB-based nanomedicine against IBD in living animals, offering hope and a potential alternative treatment option for patients suffering from IBD

Design of Phase-Changeable and Injectable Alginate Hydrogel for Imaging-Guided Tumor Hyperthermia and Chemotherapy

The objective of the present study was to construct an alginate (AG)-based phase-changeable and injectable hydrogel for imaging-guided tumor hyperthermia and chemotherapy. Based on the binding between the α-l-guluronic blocks of AG and calcium ions, the AG/MoS₂/Bi₂S₃-poly­(ethylene glycol) (MBP)/doxorubicin (DOX) solution formed a cross-linked hydrogel to simultaneously encapsulate MBP nanosheets and DOX within the hydrogel matrix. The in situ formed hydrogel can act as a reservoir to control the release of entrapped drug molecules, and the doped MBP nanosheets and DOX can realize computed tomography/photoacoustic dual-modal imaging-guided in vivo tumor photothermal therapy and chemotherapy, respectively. The AG/MBP/DOX hydrogel exhibited excellent photothermal conversion properties with mass extinction coefficient of 45.1 L/g/cm and photothermal conversion efficiency of 42.7%. Besides, the heat from the photothermal transformation of MBP can promote drug diffusion from the hydrogel to realize on-demand drug release. Additionally, the hydrogel system can restrain MBP and DOX from entering into the blood stream during therapy, and therefore substantially decrease their side effects on normal organs. More importantly, the drug loading of the AG hydrogel was general and can be extended to the encapsulation of antibiotics, such as amoxicillin, for the prevention of postoperative infections