Irreversible thermal hydrogelation and conformational switching behavior of an amphiphilic foldamer

ORGN 194

Valerie J. Bradford and Brent L. Iverson. Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station, A5300, Austin, TX 78712
Previously, we reported the irreversible hydrogelation behavior of an amphiphilic aromatic electron donor-acceptor oligomer utilizing alternating leucine and aspartic acid linkers. We have now synthesized and fully characterized a series of these amphiphilic foldamers by substituting valine, isoleucine, and norleucine in place of leucine. The hydrogel characteristics, including the elasticity and charge-transfer absorbance, follow a trend of hydrophobicity of the side chains. Further characterization suggests additional order within the hydrogel and a fibrillar structure. The results have provided insight into the kinetic and thermodynamic landscape of the hydrogelation process mirroring the conformational switching of amyloid proteins.