Scanning probe microscopy (SPM) has discovered interesting morphological anomalies of a recently developed form of quadruplex DNA bound to a model silicate substrate, mica. To better understand these anomalies, the mechanical, chemical and electronic characteristics of both duplex and quadruplex DNA have been initially characterized under controlled conditions. The self-assembled quadruplex DNA, a biopolymer Guanine-quarter DNA called """"""""G-wires"""""""", preferentially orient themselves over a period of time on mica. At low concentrations, the G- wires appear to orient parallel to the next nearest neighbor of mica's atomic surface. AT high concentrations G-wires provide reproducible """"""""networked patterns"""""""" and can be easily manipulated with SPM probe. The self-assembled G-wires can be grown to micrometer lengths in specific ionic environments through the overlap of repeated G4T2G4 (Tet 1.5) oligonucleotide sequences. Compared to poorly conducting double- stranded DNA G-wires incorporate a structure that includes caged cations and extensive hydrogen bonding that may be electrically conductive. Additionally, the uninterrupted nanometer-scale studies have shown the simple macroscopic tests used for conductivity can reliably be accomplished at the molecular level. The potential of organic nanometer- scale current carriers, or """"""""non-wires"""""""", could have a profound impact on the biotechnology industry.
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