14
2 Surface Reactions and Fabrication of Bioreactive Platforms …
Fig. 2.4 Schematic of the functionalization, covalent coupling of amino-functionalized
(bio)molecules on SAMs
by both solution- and vapor-phase reactions. Pan et al. reported on the esterification
of SAMs of 16-mercapto-1-hexadecanol with trifluoroacetic anhydride [23].
The reaction of halogen-bearing SAMs was found to be also difficult; here the
rate of reaction was much slower on a monolayer compared to reactions carried
out in solution. In a separate study, the electrophilicity of halogen was shown to
possess a significant influence on the reactivity of the monolayer. The higher the
electrophilicity, the easier the reaction of the monolayer was found.
2.2.1.3 Application of SAMs to Generate Biointerfaces
The immobilization of biomolecules on SAMs can be achieved via various routes
as summarized in Sect. 2.1. In the subsequent sections we focus on the covalent
attachment of biomolecules on SAMs owing to the robustness of the attachment and
the relevance for the remainder of this book.