Zareie M H, Sahin F I, Ergün M A, Koçum C, Menevşe S, Menevşe A, Pişkin E
Chemical Engineering Department, Hacettepe University, Beytepe, Ankara, Turkey.
Int J Biol Macromol. 1998 Jul;23(1):7-10. doi: 10.1016/s0141-8130(98)00004-x.
Genomic DNA was obtained from peripheral blood samples of healthy volunteers and interacted with two fluorescent dyes (i.e. Hoechst 33,258 and ethidium bromide) in aqueous media. These media containing DNA-dye complexes deposited on the gold coated mica surfaces. Then, STM images were obtained in which the STM was operated in air at atmospheric pressure with a tip-to-substrate bias voltage of 250-1000 mV (sample positive) and the tunneling currents in the range of 10-20 pA by using etched tips of Pt/Ir, in constant current mode. Both dyes from molecular clusters on DNA. While, the Hoechst molecules were observed on the DNA chains at regular distances, the ethidium bromide molecular clusters did not.
从健康志愿者的外周血样本中提取基因组DNA，并使其在水性介质中与两种荧光染料（即Hoechst 33,258和溴化乙锭）相互作用。这些含有DNA-染料复合物的介质沉积在涂金云母表面上。然后，通过使用Pt/Ir蚀刻尖端，在大气压力下于空气中操作扫描隧道显微镜（STM），以250-1000 mV的尖端-底物偏置电压（样品为正）和10-20 pA范围内的隧穿电流，在恒流模式下获得STM图像。两种染料都来自DNA上的分子簇。然而，在DNA链上以规则距离观察到了Hoechst分子，而溴化乙锭分子簇则未观察到。
