為了在大氣條件下以掃描穿隧顯微術觀測DNA分子，必須將DNA分子固定於導體基 質上。退火黃金符合充當導體基質的最佳要求。為克服溶液與大氣間的表面張力強行拖 移DNA分子，退火黃金表面須以半胱胺修飾，藉以定住DNA分子於基質上。本實 驗藉此而成功觀測到許多個別DNA分子的分佈影像。

In order to visualize DNA molecules in ambient environment by Scanning Tunneling Microscopy (STM), it is essential to immobilize DNA on conducting substrate. Annealed gold can meet the best criteria as the solid substrate in STM. To overcome the dragged force on DNA molecules due to surface tension between solution and air, annealed gold was modified by a monolayer of cysteamine that could immobilize DNA on the substrate. A successful spreading of individual DNA molecules was obtained and reported here.