Halloysite Nanotubes, Nucleotides, and DNA Study: Easy Fabrication of Natural Polyelectrolyte-Nanoclay CompositesAuthor(s): Ross Jones
The ability of biopolymers to function as materials building blocks can be considerably influenced by their complexation with Halloysite Nanotubes (HNTs). We investigated the manufacture of halloysite nanotubes compounds with nucleotides and genomic DNA in this study. UV spectroscopy was used to examine the binding of DNA and other nucleotide species (polyAU, UMP Na2, ADP Na3, dATP Na, AMP, uridine, and ATP Mg) to halloysite nanotubes. Different nucleotide binding to the nanoclay varied but was minimal in both the presence and absence of MgCl2; however MgCl2 considerably improved the binding of longer molecules like DNA and polyAU. Measurements of potentials confirmed that the nanotubes had been modified with DNA and nucleotide species. Transmission Electron Microscopy (TEM), atomic force microscopy (AFM), and hyperspectral microscopy were used to examine DNA-Mg-modified nanotubes. Thermogravimetric analysis confirmed DNA sorption by the nanotubes, and changes in the surface adhesion force determined by AFM suggested the presence of DNA on the nanotube surface. After adding phosphate buffered saline, DNA bound by halloysite in the presence of MgCl2 might be partially freed.