Investigation of drug-protein interactions and the drug-carrier concept by the use of branched polypeptides as model systems. Synthesis and characterization of the model peptides

Synthesis of branched polypeptides with a new design of variations in surface topography is described. The side chains of the poly(Lys-(DL-Alam)) were elongated by single amino acids (L-Tyr, L-Glu, L-His, L-Leu, L-Pro, L-Phe) or short polymers (L-, D-Glu, L-Tyr, L-, D-, DL-Lys). Single amino acids were coupled, via the azide, active ester or N-carboxy anhydride method, oligomers were grafted by the polymerisation of N-carboxy anhydride derivatives. The resulting polypeptides were characterised by amino acid analysis, identification of the N-terminal residue of the chain ends, determination of the sedimentation coefficient and molecular weight estimation, based on sedimentation experiments and thin layer gel chromatography.