In comparison to thermal fusion and solvent bonding, chemical bonding allows for simultaneous functionalization of the inner surface of microchannels as the reactive chemical groups induced for bonding the two layers can also be incorporated for further covalent attachment of biomolecules. The other advantage of this method is the superior bonding strength as a result of covalent bonding of layers. Moreover, it is possible to conduct the bonding at low temperatures and pressures, which preserves the precision of the channels' geometry better than thermal and solvent bonding 101 . The disadvantage of this method is the many steps involved for chemical treatment of the layers, which makes it troublesome for commercialization. with permission from ACS publications.