Block co-polypeptide and hydrogels made thereof

Disclosed is a block co-polypeptide comprising at least two blocks T and at least one block S, with blocks T and S alternating, wherein each T independently denotes a Trimerizing Block being a polypeptide block capable of forming a thermoreversible collagen-like triple helix structure, and whereineach S independently denotes a Spacer Block S being a polypeptide neither forming a collagen-like triple helix. The block co-polypeptide is capable of forming a gel, and is useful as an animal-free, biocompatible substitute for gelatin. Uniquely, the polypeptide allows the independent controlling of the melting temperature of the gel, the stiffness and crosslink density of the gel, the lower critical gel-forming concentration related to the length of the molecules, and unrelated (e.g. biological, physiological, pharmaceutical or signalling) functions of the molecule.