Full text loading...
(Color online) (a) Laser surface heating setup. The laser is introduced to fluorescence microscope. The thin chamber is made by using diameter polystyrene bead spacer and sealed by silicone grease. The upper surface has a metal coated layer which can absorb IR energy. (b) Temperature profile measured from temperature sensitive dye measurement (BCECF, in tris buffer, ). Temperature induced by laser heating is fitted with Lorentz profile (blue line). IR laser power is before objective lens. (c) Temperature gradient profile calculated from the fitting curve of (b).
(Color online) (a) DNA stretching by temperature gradient scheme. One end of DNA is tethered to the substrate. Temperature gradient is controlled by varying separation between laser center and tethered point. (b) One end tethered DNA fluorescence distribution. Left: without laser heating. Right: with laser heating; the distance between tethered end and laser is 6.7 and . The scalar bar is . The lower graphs are the intensity distribution in the temperature gradient direction. (c) The relation between the extension of one end tethered DNA (end to end distance) and the separations from laser heating spot.
(Color online) (a) Stretching of two end tethered DNA by temperature gradient and force balance scheme. tension and normal forces to DNA string per unit length. (b) DNA stretching for different laser powers. From left to right, no heating; 17.5, 19.5, and . The scalar bar is .
Tensions and normal force per unit length, , of the two end tethered DNA for different laser powers.
Article metrics loading...