Langmuir Monolayers and Thin Films of Amphifilic Thiacalix[4]arenes. Properties and Matrix for the Immobilization of Cytochrome c

Formation and properties of Langmuir films of thiacalix[4]­arene (TCA) derivatives containing N-donor groups on the lower rim (YO­(CH₂)₃CN; OCH₂CN; NH₂; OCH₂ArCN-p) in 1,3-alternate conformation on aqueous subphase and solid substrates have been studied. Only tetra-cyanopropoxy-p-tert-butylthiacalix­[4]­arene 1 forms a typical monomolecular layer with perpendicular orientation of the macrocycle relative to the water–air interface that is able to immobilize cytochrome c in the entire range of the surface pressure. Obtained monolayers were transferred by Langmuir–Schaefer technique onto quartz, indium–tin oxide (ITO), and silicon. It was demonstrated that protein activity is retained after immobilization on the substrate.