Biosafe, rapid, and ultrahigh‐capacity endotoxin purification in blood by a sustainable and recyclable MOF‐functionalized chitin microsphere adsorbent

Abstract Sepsis is responsible for approximately 5.3 million deaths globally each year. Here, we constructed hierarchical chitin microspheres loaded with MOF‐919 (Ch/metal–organic frameworks [MOFs]) for the rapid and efficient removal of lipopolysaccharide (LPS) in complex blood environments. Furthermore, abundant active sites on MOF‐919(Sc) also enable a record‐high adsorption capacity of 9.56 mg/g in biomass‐based adsorbents due to the coordination interactions between endotoxin and MOF‐919(Sc). The LPS level of sepsis rabbits was less than 2 EU/mL (clearance rate >95%) after 90‐min hemoperfusion, showing no adverse effect on the rabbit organs. Additionally, compared to the commonly used LPS scrubber Toraymyxin (polymethyl methacrylate), the chitin adsorbent is significantly more cost‐effective and environmentally friendly. The preparation strategy for hierarchical porous microspheres offers notable advantages in designability, recyclability, and renewability, providing a new approach to sepsis treatment and promising prospects for the biomedical application of sustainable biomass materials.