Noncontact microbiota transplantation by core-shell microgel-enabled nonleakage envelopment

Transplantation of beneficial bacteria to specific microbiota has been widely exploited to treat diseases by reshaping a healthy microbial structure. However, direct exposure of exogenous bacteria in vivo suffers from low bioavailability and infection risk. Here, we describe a noncontact microbiota transplantation system (NMTS) by core-shell microgel-enabled nonleakage envelopment. Bacteria are encapsulated into the core of core-shell microgels via two-step light-initiated emulsion polymerization of gelatin methacrylate. NMTS is versatile for biocontainment of diverse strains, showing near complete encapsulation and negligible influence on bacterial activity. As a proof-of-concept study on probiotic transplantation to the gut microbiota, NMTS demonstrates the shielding effect to protect sealed bacteria from intraluminal insults of low pH and bile acid, the toughness to prevent bacterial leakage during entire gastrointestinal passage and reduce infection risk, and the permeability to release beneficial metabolites and reconstruct a balanced intestinal microbial structure, proposing a contactless fashion for advanced microbiota transplantation.