Fig. 5. Examining tetrapeptide self-assembly through (a) solid state 13C NMR and (b) gel state NMR. Comparing the spectra reveals β-sheet formation for Fmoc-FKFK and increased aromatic flexibility for Fmoc-FKKF and Fmoc-KFFK. Solid state NMR measurements were conducted using lyophilised peptides and gel state NMR measurements were recorded at a concentration of 1% (w/v) in D2O, where gelation was triggered through the addition of deuterated PBS (pD 7.4).
