Infrared-visible sum-frequency generation (SFG) spectroscopy is used to study the recognition of a protein (avidin) by a derivated vitamin (biocytin). No interaction is observed when the measurements are performed on metallic substrates in the normal co-propagative configuration. When the biocytin layer is deposited on a CaF2 substrate and the SFG measurements are performed in the total internal reflection configuration, drastic modifications in the C-H and N-H spectral ranges attest the molecular recognition of avidin by biocytin. The specificity of the recognition process is confirmed by replacing avidin by other proteins.
|Number of pages||9|
|Publication status||Published - 2003|