Figure 1.

(A) Chemical structure of EM; (B) schematic diagram of charge distribution and three-dimensional molecular model of self-assembling peptide RADA16-I; (C) a scheme of RADA16-I self-assembly through hydrophobic interaction and ionic-complementarity; (D) a proposed model of RADA16-I self-assembly to form nanofiber structures (Liu et al., 2011) and schematic representation of the interaction between hydrophobic drugs and RADA16-I. Oxygen atoms are red, nitrogen atoms are blue, carbon atoms are white, and hydrogen atoms are gray. In this conformation, all of the hydrophobic alanine side chains are aligned on one side, and all of the arginine and aspartic acid side chains are aligned on different sides to produce two different faces: the hydrophobic and the hydrophilic. On the polar side, arginine alternates with aspartic acid. The dimensions are about 5 nm in length, 1.3 nm in height, and 0.8 nm in width.