In a new study appearing in Science Advances, researchers from Southwest Jiaotong University and elsewhere describe a method to develop a nanomedicine to treat inflammatory bowel disease (IBD). Previous studies had suggested that oxidative stress and gut microbial disturbances are crucial IBD triggers. As a result, many studies have focused on developing intravenous and oral delivery of small interfering RNA (siRNA) nanomedicines that reduce inflammatory cytokines and scavenging reactive oxygen species, thereby reducing oxidative stress in IBD. However, those modes of delivery are plagued with problems such as insufficient residence time and low targeting efficiency for inflamed colons. The new method the researchers developed — a polyphenol-armored nanomedicine — aims to overcome many of these problems. This nanomedicine includes TNF-α-siRNA, a gallic acid-mediated graphene quantum dot-encapsulated bovine serum albumin nanoparticle, and a chitosan and tannin acid multilayer shell, which the researchers referred to as the medicine's "armor." According to the researchers, the nanomedicine "suppressed hyperactive immune responses and modulated bacterial gut microbiota homeostasis in a mouse model of acute colitis" and could suppress intestinal inflammation and improve anxiety, depression, and cognitive behavioral functions. "Overall, this polyphenol-armored strategy offers a universal, powerful platform for the design of oral nanomedicines for inflammatory diseases," they add.