ABSTRACT
The joining of two or more components, either biological molecules or otherwise, can be achieved by enzyme catalysis, caused by activating agents, or facilitated by cross-linking reagents containing two or more reactive groups. The last strategy seems to be the most common and logical approach. With two group-speciŠc reagents linked through a spacer, bifunctional cross-linkers will react with speciŠc functional groups within a molecule or between two different molecules resulting in a bond between these two components. In addition, multifunctional cross-linkers can also be designed. The reactive groups in a cross-linker can be identical or different, providing a diversity of reagents that can bring about covalent bonding between a wide range of chemical species, either intra-or intermolecularly.
