Several different cyclodextrinthiol derivatives have been immobilized on gold surfaces through a chemisorption process to form films which exhibit significantly different features. Three monothiolated cyclodextrin derivatives with different spacers between the cyclodextrin cavity and the thiol group and a mixture of multithiolated cyclodextrins were synthesized and characterized. Chemisorption of these compounds onto gold surfaces gave films which were investigated by Fourier transform infrared (FTIR) spectroscopy, time-of-flight mass spectrometry, contact angle measurements, plasmon surface polariton (PSP) spectroscopy, and cyclic voltammetry. It was found that the chemical structure of each cyclodextrin derivative had a strong influence on the molecular architecture in the resulting films, and in particular on the orientation of the cyclodextrin torus. Models were developed to describe the molecular arrangement in the films.

In a previous paper we could demonstrate the immobilization of mono-and multithiolated cyclodextrins on gold surfaces and investigated the film properties. In this paper we follow the self-assembly processes in time by optical and physicochemical methods for those three monothiolated and a mixture of multithiolated cyclodextrin derivatives. The formation of cyclodextrin films on gold substrates was found to be a multistep process involving an activation energy.

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