(598b) Magnetic Nanoparticle Clusters for Efficacious Bilirubin Removal from Body Fluids

Accumulation of bilirubin in the blood of patients suffering from end-stage liver disease severely compromises their health and prospects for survival¹. Hyperbilirubinemia - if left untreated - may cause hepatic encephalopathy leading eventually to irreversible damage to the brain². Traditional extracorporeal blood purification techniques and liver support devices only poorly remove bilirubin and suffer from membrane saturation and clotting³. Magnetic blood purification based on the capturing of toxins and pathogens by freely diffusing magnetic nanoparticles may offer an attractive alternative⁴. Here, we report on the functionalization of 100 nm superparamagnetic magnetite cluster nanoparticles functionalized with cationic polymer brushes grown using Surface Initiated ATRP for bilirubin capturing from body fluids. We demonstrate that the bilirubin removal capacity depends on the brush length and composition. Batch extraction efficiencies of more than 99% were found for bead concentrations of 1mg/mL and extraction/separation times of less than two minutes. While the most efficacious capturing agents were also the most cytolytic ones, significant bilirubin removal efficiencies of 40% could be obtained at minimal bead concentrations of 25µg/mL in albumin rich solutions. At these low concentrations, cytolytic activity remained indistinguishable from untreated controls. Taken together, we demonstrate the feasibility of quantitative bilirubin capturing by polymer-functionalized magnetic nanoparticles with prospective implications for artificial liver support.

References

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