Mixtures of synthetic copolypeptide hydrogels

A composition comprising a first copolypeptide comprising Substructure I, a second copolypeptide comprising Substructure II, a third copolypeptide comprising Substructure III, and water, wherein Substructure I is depicted as follows:

• —Xm—Cp— Substructure I;
• Substructure II is depicted as follows:
• —Yn—Aq— Substructure II;
• Substructure III is depicted as follows:
• —Zr—Dt— Substructure III;
• each instance of X is an amino acid residue independently selected from a non-ionic, hydrophilic amino acid, sarcosine, glycine, and alanine;
• each instance of Y is an amino acid residue independently selected from a non-ionic, hydrophilic amino acid, sarcosine, glycine, and alanine;
• each instance of Z is an amino acid residue independently selected from a non-ionic, hydrophilic amino acid, sarcosine, glycine, and alanine;
• in at least 20% of the instances of C, C is an amino acid residue independently selected from a cationic, hydrophilic amino acid;
• in at least 20% of the instances of A, A is an amino acid residue independently selected from an anionic, hydrophilic amino acid;
• in at least 20% of the instances of D, D is an amino acid residue independently selected from a non-ionic, hydrophobic amino acid;
• m is about 100 to about 600;
• n is about 100 to about 600;
• r is about 100 to about 600;
• p is about 20 to about 200;
• q is about 20 to about 200;
• t is about 10 to about 200;
• at least 90 mol % of the C amino acid residues are (D)-amino acid residues or at least 90 mol % of the C amino acid residues are (L)-amino acid residues;
• at least 90 mol % of the A amino acid residues are (D)-amino acid residues or at least 90 mol % of the A amino acid residues are (L)-amino acid residues;
• and
• at least 90 mol % of the D amino acid residues are (D)-amino acid residues or at least 90 mol % of the D amino acid residues are (L)-amino acid residues;
• the first copolypeptide and the second copolypeptide are not covalently linked to the third copolypeptide;
• the total concentration of the first copolypeptide and the second copolypeptide is about 1% to about 15%;
• and
• the concentration of the third copolypeptide is about 1% to about 10%.