Geometric properties of covalently bonded DNA on single-crystalline diamond.
Diamond is a promising candidate for bioapplications. Properties of hybridized DNA arrays on single-crystalline diamond are studied on a microscopic level by atomic force microscopy (AFM) in buffer solutions. Compact DNA layers in a thickness of 76 A are resolved by optimizing phase and height contrast in AFM. The height shows some long-range (30 nm) undulations of +/-5 A due to tip and DNA interactions. The axis of double helix DNA is oriented at about 36 degrees with respect to the diamond surface. DNA molecules can be removed by contact-mode AFM with forces >45 nN, indicating stronger DNA bonding than on gold substrates.
Diamond Research Center, AIST, Central 2, 1-1-1, Umezono, Tsukuba, Ibaraki 305-8568, Japan.
Bohuslav
B
Rezek
Dongchan
D
Shin
Takako
T
Nakamura
Christoph E
CE
Nebel
D004247:DNA / Q000737:chemistry*; D018130:Diamond / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D013499:Surface Properties
D018130:Diamond; D004247:DNA