Polymer Resins with Amino Acid Containing Pendants for Sorption of Bilirubin. I. Comparison of Merrifield and Polyamide Resins

Merrifield resins with various amino acid containing pendants and a water swellable polyamide resin with the peptide alanine-alanine-alanine-arginine as the pendant group have been prepared by solid phase peptide synthesis. Merrifield resins with either arginine or lysine pendants are capable of sorbing bilirubin from aqueous solution (pH = 7.8) but those with other amino acid pendants gave no indication of sorption. The polyamide-arginine resin showed, on a functional group basis, a higher capacity for bilirubin than does cholestyramine. It is proposed that the formation of salt linkages causes a strong interaction of bilirubin with arginine and lysine.