Geometric Properties of Covalently Bonded DNA on Single-Crystalline Diamond

Abstract

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‐based DNA sensors: surface functionalization and read‐out strategies

“…The density, orientation and binding strength of DNA to mono-and polycrystalline diamond surfaces have been investigated by AFM measurements in buffer solutions [62,[84][85][86]. In particular, nano-shaving experiments are used: part of the functionalized surface is mapped by tapping mode AFM, then a smaller area is selected and scanned in contact mode AFM, removing the organic top-layer.…”

Nanoindentation as a Tool to Clarify the Mechanism Causing Variable Stiffness of a Silane Layer on Diamond

“…Several pioneering works, reporting the properties of polymer layers, formed on a diamond surface, describe testing of the layers on Hterminated diamond by scratching with an AFM cantilever [28,29,31,32]. Since different proteins require different treatments for maintaining their activities, an intervening layer needs the adjustment of thickness, roughness, and stiffness.…”

Luminescent nanodiamonds for biomedical applications

“…In one study, the application of nanodiamonds to the skin of mice did not cause contact hypersensitivity or other allergic reactions (Burleson et al 2009). At a dose of 1mg/kg, Other -DNA (Christiaens et al 2006;Takahashi et al 2003;Knickerbocker et al 2003;Lu et al 2004;Rezek et al 2006;Yang et al 2002) -DNA (Ushizawa et al 2002) (ester linkage) Table 6 Cells showing good biocompatibility with nanodiamond in vitro HeLa cells (human cervical carcinoma) (Faklaris et al 2008;Vaijayanthimala et al 2009) Human lung adenocarcinoma cells Liu et al 2007;Liu et al 2009) Keratinocytes (Burleson et al 2009;Schrand et al 2007) Neuroblastomas (Schrand et al 2007) PC-12 cells (Schrand et al 2007) Lung fibroblasts Embryonic fibroblasts Vaijayanthimala et al 2009) Human kidney cells Osteoprogenitor cells (Vaijayanthimala et al 2009) Macrophages (Schrand et al 2007) 4 nm nanodiamonds instilled into the mouse trachea were phagocytosed by alveolar macrophages within 24 h, with a decrease in the number of nanodiamonds observed in the alveolar area throughout the study. Histopathological and ultrastructural investigations at 7, 14 and 28 days postexposure also showed no adverse effects in the lungs; nor did nanodiamonds evidently translocate into the bloodstream and/or other organs (Yuan et al 2010).…”