文献类型：期刊文献

英文题名：Time-Resolved Probes Based on Guanine/Thymine-Rich DNA-Sensitized Luminescence of Terbium(III)

作者：Zhang, Min[1];Le, Huynh-Nhu[1];Jiang, Xiao-Qin[1];Yin, Bin-Cheng[1];Ye, Bang-Ce[1]

机构：[1]E China Univ Sci & Technol, Lab Biosyst & Microanal, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2013

卷号：85

期号：23

起止页码：11665

外文期刊名：ANALYTICAL CHEMISTRY

收录：;EI(收录号：20135017072106);WOS:【SCI-EXPANDED(收录号:WOS:000327999800068)】；

基金：This study is supported by the China NSF (21075040, 21335003), the Shanghai Fund (11 nm0502500), and the Key Grant Project (No. 313019) of Chinese Ministry of Education, and the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Oligonucleotides - Probes - Ligands - Positive ions - Antennas - Energy transfer - DNA - Luminescence - Silver compounds

摘要：In this study, we have developed a novel strategy to highly sensitize the luminescence of terbium(III) (Tb3+) using a designed guanine/thymine-rich DNA (5'-[G(3)T](5)-3') as an antenna ligand, in which [G(3)T](5) improved the luminescence of Tb3+ by 3 orders of magnitude due to energy transfer from nucleic acids to Tb3+ (i.e., antenna effect). Furthermore, label-free probes for the luminescent detection of biothiols, Ag+, and sequence-specific DNA in an inexpensive, simple, and mix-and-read format are presented based on the [G(3)T](5)-sensitized luminescence of Tb3+ (GTSLT). The long luminescence lifetime of the probes readily enables time-resolved luminescence (TRL) experiments. Hg2+ can efficiently quench the luminescence of Tb3+ sensitized by [G(3)T](5) (Tb3+/[G(3)T](5)); however, biothiols are readily applicable to selectively grab Hg2+ for restoration of the luminescence of Tb3+[G(3)T](5) initially quenched by Hg2+, which can be used for "turn on" detection of biothiols. With the use of cytosine (C)-rich oligonucleotide c[G(3)T](5) complementary to [G(3)T](5), the formed [G(3)T](5)/c[G(3)T](5) duplex cannot sensitize the luminescence of Tb3+. However, in the presence of Ag+, Ag+ can combine the C base of c[G(3)T](5) to form C-Ag+-C complexes, leading to the split of the [G(3)T](5)/c[G(3)T](5) duplex and then release of [G(3)T](5). The released [G(3)T](5) acts as an antenna ligand for sensitizing the luminescence of Tb3+. Therefore, the Tb3+[G(3)T](5)/c[G(3)T](5) probe can be applied to detect Ag+ in a "turn on" format. Moreover, recognition of target DNA via hybridization to a molecular beacon (MB)-like probe (MB-[G(3)T](5)) can unfold the MB-[G(3)T](5) to release the [G(3)T](5) for sensitizing the luminescence of Tb3+, producing a detectable signal directly proportional to the amount of target DNA of interest. This allows the development of a fascinating label-free MB probe for DNA sensing based on the luminescence of Tb3+. Results and methods reported here suggest that a guanine/thymine-rich DNA-sensitized luminescence probe of Tb3+ represents a new opportunity for versatile background-free biosensing applications.