Peptide bioorthogonal functionality

In addition to the design principles just mentioned, peptides, proteins, and peptide-based supramolecular structures can be cross-linked into 3D networks via conventional synthetic chemistry (e.g., active ester chemistry or short synthetic cross-linkers) or via bioorthogonal click chemistry (e.g., Michael-type addition), utilizing their inherent multitude of functional groups (—NH, —COOH, —SH) and/or other additionally introduced functionalities. 

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