“…Moreover, the introduction of non-canonical amino acids (ncAAs), bearing highly reactive groups such as N 3 , CCH and NC, through genetic coding, significantly expands the number of functional groups that can be introduced. Traditionally, carrier-free immobilisation of enzymes 42 or whole cells 43,44 involves the use of glutaraldehyde as a cross-linker. This results in higher stability but is often accompanied by a substantial loss of activity owing to random formation of covalent bonds with reactive groups in or close to the active site.…”