Here, we investigate the family of P11 peptides that have been developed to self-assemble spontaneously to form β-sheet 3-D hierarchical structures. Figure shows the generic structure of this class of peptides, as well as the amino acid sequences and net charge of different P11 peptides . The P11 peptides are designed with a hydrophobic aromatic centre on one side and a hydrophilic side to promote the formation of anti-parallel β-sheets and then through a hierarchical self-assembly mechanism to form a fibrous multimicron scale network. An example TEM micrograph of a P11 peptide hydrogel (P11-12) illustrates the fibrous network that forms during self-assembly (Figure ). Previous work has highlighted that charge is an important factor when assessing the biocompatibility of positively charged self-assembling hydrogels, including P11-8 .