title: Synthesis and characterization of polymer-(multi)-peptide conjugates for control of specific cell aggregation.
abstract: A new synthetic approach has been applied to obtain novel di-, tetra-, and (multi)-peptide containing polymer conjugates in quantitative yields with a high degree of conjugation. Bis-(N-hydroxysuccinimidyl) esters of PEG (Mw = 200, 600, 1400, 2000, and 3400) were synthesized and studied in a condensation reaction with synthetic peptides: glycine-glycine-tyrosine-arginine (GGYR), a model peptide, and glycine-arginine-glycine-aspartic acid-tyrosine (GRGDY), a sequence known to promote cell adhesion and aggregation. Tetra-substituted derivatives of PEG-based conjugates were synthesized by coupling L-aspartic acid and L-aspartyl-L-phenylalanine through a condensation procedure in organic media. Poly(acrylic acid) and co-polymers (Mw = 2000 and 5000) were studied as a model of multifunctional linear polymers in the reaction with L-tryptophan and GGYR. Alternative polymer-(multi)-peptide conjugates were successfully synthesized using Starburst dendrimer PAMAM (G = 3), 'short' and 'long'-chain PEG-based active esters and GRGDY. The structure of the intermediate precursors and peptide-conjugates was confirmed by spectral (UV-Vis, FTIR, H-NMR) and chromatographic (RP-HPLC and SEC) methods. By varying the properties of the interconnecting polymer--such as hydrophobicity, molecular weight, and functionality--a set of polymer-GRGDY conjugates was synthesized.
authors.affiliation: School of Chemical Engineering, Cornell University, Ithaca, NY 14853, USA.
authors.forename: N
authors.initials: N
authors.lastname: Belcheva
authors.forename: S P
authors.initials: SP
authors.lastname: Baldwin
authors.forename: W M
authors.initials: WM
authors.lastname: Saltzman
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects; D002449:Cell Aggregation / Q000187:drug effects*; D004952:Esters / Q000138:chemical synthesis; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D009842:Oligopeptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013388:Succinimides / Q000737:chemistry
chemical_list: D004952:Esters; D009842:Oligopeptides; D011108:Polymers; D013388:Succinimides; D011092:Polyethylene Glycols; C078237:glycyl-glycyl-tyrosyl-arginine; C001426:N-hydroxysuccinimide