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日本京都大学研究组已用过冷电子显微镜获得了第一张假死的DNA分子的照片。他们用液氦冷却电子显微镜以提高其分辨率,从而成功地拍摄了此照片。DNA分子是在接近绝对零度时处于“冷冻水合”状态下拍摄的。电子显微镜的最大分辨率为0.6毫微米。样品的过冷保护使其免受电子的损伤。为增大样品的放大倍数,必须提高聚焦于样品上的电子束的强度,但电子束太强会破坏DNA那样的复杂分子结构。样品愈冷,这种破坏反应愈慢。他们声称,这种过冷法将电子束的破坏率降低到室温下的二十分之一
Japan’s Kyoto University team has used cold electron microscopy to obtain the first photo of suspended animation DNA molecules. They successfully taken this photograph by cooling the electron microscope with liquid helium to increase its resolution. The DNA molecule was taken in “chilled” state near absolute zero. The maximum resolution of the electron microscope is 0.6 nm. Undercooling the sample protects it from electrons. In order to increase the magnification of the sample, the intensity of the electron beam focused on the sample must be increased. However, the electron beam is too strong to destroy the complicated molecular structure like DNA. The colder the sample, the slower the damage reaction. They claim that this subcooling method reduces the rate of electron beam destruction to one-twentieth of room temperature