Preparation of Nitrogen-Doped Mesoporous Carbon for the Efficient Removal of Bilirubin in Hemoperfusion

The development of bilirubin adsorbent with high selectivity, brilliant adsorption ability, and biocompatibility is still a considerable challenge. In this study, a copolymer-templated nitrogen-doped mesoporous carbon (CTNC) has been prepared via a simple carbonization procedure of well-defined polyacrylonitrile-block-poly­(n-butyl acrylate) (PAN-b-PBA) block copolymer precursors. The structure and morphology were characterized by transmission electron microsphere (TEM), adsorption–desorption isotherms, and X-ray photoelectron spectroscopy (XPS). Owing to its high specific area, hierarchical open-porous structure, and the introduction of nitrogen atoms in graphitic sp2 network, the adsorbent CTNC exhibited high removal efficiency toward bilirubin and bile acid from human plasma. The removal rate of bilirubin was more than 50.7% with a minimal loss of albumin. Meanwhile, exceeding 95% of bile acid was eliminated. The effect of albumin on the adsorption kinetic of bilirubin was identified. The result indicated that the adsorption rate of BSA-bonded bilirubin experienced a decline than that of free bilirubin, but the adsorption capacity was still up to 39.8 mg/g within 2 h. Moreover, the effect of porosity and nitrogen contents on bilirubin adsorption ability and blood compatibility were systematically investigated. The material with lower nitrogen content showed only a negligible hemolysis activity. Therefore, the nitrogen-doped mesoporous carbon developed in this work has potential application in blood purification for the efficient removal of bilirubin.