The invention relates to a kit comprising the following individual components: (a) polymers comprising at least one free amino group, (b) bridge molecules selected from the group consisting of monocyclic ortho-dihydroxyaromates, mono-cyclic para-dihydroxyaromates, bicyclic monohydrxyaromates, polycyclic monohydroxyaromates, bicyclic dihydroxyaromates, polycyclic dihydroxyaromates, bicyclic trihydroxyaromates, polycyclic trihydroxyaromates, and mixtures thereof, and (c) polyphenoloxidases, in particular, lignolytic polyphenoloxidases, whereby the individual components b) and c) are not in contact.