Reflectometric Interference Spectroscopy RIfS in the Liquid Phase

2 Reflectometric Interference Spectroscopy (RIfS) in the Liquid Phase 

Cyclohexapeptide monolayers on quartz microbalances are able to discriminate between different analytes in the liquid phase (see Section 10.5.1). On the basis of these results, we also have immobilized cyclopeptides (Fig. 10.14) on glass transducers. In this case, the interaction between cyclopeptides and analytes was monitored by reflectometric interference spectroscopy (RIfS) [98], RIfS is an optical detection method in which the phenomenon of reflection and interference of light at phase boundaries is used to measure changes in optical thickness (refractive index x layer thickness) of transparent films 

This example shows that combinatorial variations of cyclopeptides and variation of the matrix allow the search for selectivity for other amino acids. The principle of cyclopeptide 

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