Fabrication of protein tubules: Immobilization of proteins on peptide tubules

Peptide tubules, self-assemblies of bis(N-alpha -amido-glycylglycine)-1,7-heptane dicarboxylate, were functionalized by poly(L-lysine), D-biotin, avidin, and albumin bovine. Proteins were covalently immobilized on the peptide tubules via NHS ester intermediates, while amide groups of the peptide tubules were also capable of intercalating proteins via hydrogen bonds. These entities, tagged with fluorescein isothiocyanate, uniformly coated the peptide tubules as confirmed by fluorescence microscopy. Avidin coated the peptide tubules without denaturing, confirmed by fluorescein-tagged D-biotin attachment onto the avidin-coated peptide tubules, This result indicates that the protein tubules may be attached at desired surfaces using biological interactions such as antibody-antigen recognition. Such protein tubules may be used as building blocks for microdevice fabrication such as microelectronics and protein array biosensors.