Development and validation of a fluorescence method to follow the build-up of short peptide sequences on solid 2D surfaces

The modification of material surfaces with short peptide sequences has become an essential step in many biotechnological and biomedical applications. Due to their simple architecture compared to more complex 3D substrates, 2D surfaces are of particular interest for high throughput applications and as model surfaces for dynamic or responsive surface modifications. The decoration of these surfaces with peptides is commonly accomplished by synthesizing the peptide first and subsequently transferring it onto the surface of the substrate. Recently, several procedures have been described for the synthesis of peptides directly onto a 2D surface, thereby simplifying and accelerating the modification of flat surfaces with peptides. However, the wider use of these techniques requires a routine method to monitor the amino acid build-up on the surface. Here, we describe a fast, inexpensive and nondestructive fluorescence based method which is readily accessible to follow the amino acid build-up on solid 2D samples.