Cationic Conjugated Polyelectrolyte/Molecular Beacon Complex for Sensitive, Sequence-Specific, Real-Time DNA Detection

被引：32

作者：

Feng, Xuli ^{[1
]}

Duan, Xinrui ^{[1
]}

Liu, Libin ^{[1
]}

An, Lingling ^{[1
]}

Feng, Fude ^{[1
]}

Wang, Shu ^{[1
]}

机构：

[1] Chinese Acad Sci, Inst Chem, Ke Lab Organ Solids, Beijing Natl Lab Mol Sci, Beijing 100190, Peoples R China

来源：

LANGMUIR | 2008年 / 24卷 / 21期

基金：

中国国家自然科学基金;

关键词：

D O I：

10.1021/la802932t

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A new fluorescence method has been developed for DNA detection at room temperature in a sensitive, selective. economical, and real-time manner that interfaces the superiority of a molecular beacon in mismatch discrimination with the light-harvesting property of water-soluble conjugated polyelectrolytes. The probe solution contains a cationic conjugated polyelectrolyte (PFP-NMe3+), a molecular beacon with a five base pairs double-stranded stem labeled at the 5'-terminus with fluorescein (DNA(P-)Fl), and ethidium bromide (EB, a specific intercalator of dsDNA). The electrostatic interactions between DNA(P)-Fl and PFP-NMe3+ keep them in close proximity, facilitating the fluorescence resonance energy transfer (FRET) from PFP-NMe3+ to fluorescein. Upon adding a complementary strand to the probe Solution, the conformation of DNA(P)-Fl transits into dsDNA followed by the intercalation of EB into the grooves. Two-step FRET, from PFP-NMe3+ to DNA(P)-Fl (FRET-1), followed by FRET from DNA(P)-Fl to EB (FRET-2) takes place. In view of the observed fluorescein or EB emission changes, DNA can be detected in aqueous solution. Because the base mismatch in target DNA inhibits the transition of DNA(P)-Fl from the stem-loop to duplex structure, single nucleotide mismatch can be clearly detected.

引用

页码：12138 / 12141

页数：4

共 39 条

[1] Rapid, high-throughput, multiplex, real-time PCR for identification of mutations in the cyp51A gene of Aspergillus fumigatus that confer resistance to itraconazole [J].