Electrochemical Properties of Multilayered Coatings Implementing Thiacalix[4]arenes with Oligolactic Fragments and DNA

Layer-by-layer assembling of polyelectrolyte complexes on glassy carbon electrode utilizing derivatives of p-tert-butylthiacalix[4]arene modified with oligolactic acid in cone, partial cone and 1,3-alternate configurations has been performed and characterized by atomic force microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. Structure, surface morphology and permeability of the coatings depended on the number and nature of individual layers. Configuration of macrocyclic core influenced the charge distribution and flexibility of polyelectrolytes and the electrochemical properties of the coatings. Partial substitution of oligolactic derivatives with the DNA molecules allowed distinguishing native, thermally and oxidatively damaged DNA by ferricyanide ion signals. The relationships between the coating structure and the content can be further used for development of electrochemical sensors devoted to the detection of specific DNA interactions.