Anticoagulant chitosan-kappa-carrageenan composite hydrogel sorbent for simultaneous endotoxin and bacteria cleansing in septic blood

Here, we describe a green approach to fabricate genipin crosslinked chitosan-kappa-carrageenan composite hydrogels (C-K hydrogels) aiming at reducing endotoxin level and bacteria burden in septic blood synchronously. The chemical compositions and morphologies of the developed C-K hydrogels were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. The C-K hydrogels significantly inhibited adverse blood-material interactions such as hemolysis, complement activation, platelet activation and contact activation, and exhibited better anticoagulant properties than raw chitosan hydrogels. Most importantly, the optimized C2-K1 hydrogels were competent to eliminate 63.3 % of endotoxin in septic blood with a maximum adsorption capacity of 95.0 EU/g during a 3-h simulative hemoperfusion procedure. Bacteria cleansing experiments further demonstrated that the optimized C2-K1 hydrogels effectively decreased 46.0 % of E. coli and 68.7 % of S. aureus load, respectively. It is believed that the C-K hydrogels are promising hemoperfusion sorbents to treat severe septic patients.