Formation of Two Dimensional Network Structure of DNA Molecules on Highly Ordered Pyrolytic Graphite Surface

Unique DNA network structures have been constructed, when DNA solutions (concentration range from 50 µg/ml to 500 µg/ml) are spread on mica and highly ordered pyrolytic graphite (HOPG) surfaces. The DNA network structures depend on the fixation time, solution concentration and substrate adhesion force. A novel structure having a hexagonal symmetry has been found on the HOPG surface for the first time. HOPG is one of the promising substrates for photoemission analysis without any charge up problem. Clear C (1s), N (1s), O (1s) and P (2p) peaks corresponding to DNA molecules can be detected.