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Monitoring molecular beacon/DNA interactions using atomic force microscopy.

Yan Jin·Kemin Wang·Weihong Tan·Ping Wu·Qing Wang·Hongmei Huang·Shasheng Huang·Zhiwen Tang·Qiuping Guo
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Abstract

The molecular beacon (MB) is a new fluorescence probe containing a single-stranded oligonucleotide with a probe sequence embedded in complementary sequences that form a hairpin stem. Due to the inherent fluorescent signal transduction mechanism, an MB functions as a sensitive probe with a high signal-to-background ratio for real-time monitoring and provides a variety of exciting opportunities in DNA, RNA, and protein studies. To better understand the properties of MBs, the specific interactions between MB and target DNA (complementary and one-base mismatch) have been directly investigated by atomic force microscopy. The interaction force between a linear DNA probe and the target DNA was also detected and compared to that between MB and target DNA. The results demonstrate the high specificity of the MB/target DNA compared to the linear DNA/target DNA interaction.

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DNADNA ProbesFluorescent DyesMicroscopy, Atomic ForceJournal ArticleResearch Support, Non-U.S. Gov't

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Yan Jin, Kemin Wang, Weihong Tan, Ping Wu, Qing Wang, Hongmei Huang, Shasheng Huang, Zhiwen Tang, Qiuping Guo. 2004-10-01. Monitoring molecular beacon/DNA interactions using atomic force microscopy.. https://doi.org/10.1021/ac049933u

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