The effect of PEO length on the self-assembly of poly(ethylene oxide)-tetrapeptide conjugates prepared by "Click" chemistry.
Two series of poly(ethylene oxide)-tetrapeptide conjugates have been prepared using a "Click" reaction between an alkyne-modified tetra(phenylalanine) or tetra(valine) and various azide-terminated poly(ethylene oxide) (PEO) oligomers. Three different PEO precursors were used to prepare these conjugates, with number-average molecular weights of 350, 1200, and 1800 Da. Assembly of mPEO-F4-OEt and mPEO-V4-OEt conjugates was achieved by dialysis of a THF solution of the conjugate against water or by direct aqueous rehydration of a thin film. The PEO length has a profound effect on the outcome of the self-assembly, with the F4 conjugates giving rise to nanotubes, fibers, and wormlike micelles, respectively, as the length of the PEO block is increased. For the V4 series, the propensity to form beta-sheets dominates, and hence, the self-assembled structures are reminiscent of those formed by peptides alone, even at the longer PEO lengths. Thus, this systematic study demonstrates that the self-assembly of PEO-peptides depends on both the nature of the peptides and the relative PEO block length.
Tzokova
Nadia
N
Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, S3 7HF, United Kingdom.
Fernyhough
Christine M
CM
Butler
Michael F
MF
Armes
Steven P
SP
Ryan
Anthony J
AJ
Topham
Paul D
PD
Adams
Dave J
DJ
D002942:Circular Dichroism; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D008970:Molecular Weight; D043942:Nanotubes / Q000737:chemistry; D009842:Oligopeptides / Q000138:chemical synthesis* / Q000737:chemistry*; D010649:Phenylalanine / Q000737:chemistry; D011092:Polyethylene Glycols / Q000138:chemical synthesis / Q000737:chemistry*; D014633:Valine / Q000737:chemistry
D008823:Micelles; D009842:Oligopeptides; D011092:Polyethylene Glycols; D010649:Phenylalanine; D014633:Valine