Figure 1.

Solubility versus self-assembly of tripeptides

(A and B) Water solubility of AFA relative to (A) temperature and (B) pH of the solution. The insets in (A) show images of the solution at three different temperatures. The data represent the mean ± SEM for 3 independent experiments.

(C) Solubility of AFA in the presence of different concentrations of NaCl. The data represent the mean ± SEM for 3 independent experiments.

(D and E) Comparison of the critical concentrations of AFA, AAF, and FAA at different (D) temperature and (E) pH values. The inset in (D) shows a magnified graph for AAF and FAA.

(F) Calculated Stokes hydrodynamic diameter distribution of three tripeptide clusters in solution at different concentrations at pH 6.8 and room temperature.

(G–N) Scanning electron microscopy images of the resultant architectures after 2 weeks of self-assembly of (G–J) AFA, (K and L) AAF, and (M and N) FAA. The top panels show the entire area of the solution drop, and the corresponding magnified areas marked by green squares are shown in the bottom panels. The insets in (L) and (N) show the probability distribution of fiber width.

(O–Q) FTIR spectra of (O) AFA, (P) AAF, and (Q) FAA.