Controllable polyvinylpyrrolidone modified Polystyrene divinylbenzene for efficient adsorption of bilirubin and improvement of hemocompatibility

Abstract

Bilirubin, a dangerous toxin may lead to serious brain injury, can be widely removed by hemoperfusion. However, the hemoperfusion adsorbents with higher removal ability, excellent hemocompatibility and biocompatibility still need to be explored. In this work, a novel functionalized polyvinylpyrrolidone (PVP) was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Then PVP-modified polystyrene-divinylbenzene (PS-DVB-PVP) microspheres were prepared by a one-pot restore-click method. The results showed that the adsorption capacity and rate of microspheres for bilirubin were increased after modification with PVP. In the hemocompatibility and biocompatibility test, the modified microspheres demonstrated higher resistance to human serum albumin (HSA) and excellent hemolysis rate. In order to study the role of PVP in the bilirubin-adsorption process, isotherms were fitted by Langmuir model and Freundlich model, while kinetics data were fitted by pseudo-second-order model and intraparticle diffusion model. In addition, the modified microspheres showed no difference with unmodified microspheres in the coagulation test and exhibited no cytotoxicity to L929 cells. These results showed that our modified microspheres have both excellent hemocompatibility and outstanding biocompatibility, which will not cause hemolysis and coagulation. All these results made them possible to become a new adsorbent for efficient removing bilirubin in hemoperfusion.