Dual-functionalized polymer nanotubes as substrates for molecular-probe and DNA-carrier applications

Bifunctionalized polymer nanotubes have been fabricated using vapor-deposition polymerization in FeCl3-adsorbed anodic aluminum oxide membranes followed by attachment of amine-functionalized silica nanoparticles. The prepared bifunctionalized polymer nanotubes are applied as both a molecular probe and a DNA carrier by conjugating pyreneacetic acid with the amine groups and immobilizing DNA with the carboxylic acid groups on the surface. The number of amine functional groups on the nanotubes' surface can be measured by means of the photoluminescence intensity of pyreneacetic acid conjugated with aminea-transgroups, and the number of the residual carboxylic acid groups is calculated by titration with sodium hydroxide. Fourier form infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy, and confocal laser scanning microscopy have been performed to confirm the complete polymerization of the monomer and the attachment of photoluminescent molecules and single-stranded DNA.