CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Analyst. 2013 Apr 21;138(8):2302-7. doi: 10.1039/c3an36795a.
A terbium based fluorescent probe was synthesized by coordinating terbium ions with a designed oligonucleotides (5'-ATATGGGGGATAT-3', termed GH5). GH5 improved the fluorescence of terbium ions by four orders of magnitude. The fluorescence enhancement of terbium ions by different oligonucleotides sequences indicated that the polyguanine loop of the hairpin GH5 is key to enhance terbium ion emission. The quantum yield of Tb-GH5 probe was 10.5% and the probe was photo-stable. The result of conductivity titration indicated that the stoichiometry of the probe is 3.5 Tb: 1 GH5, which is confirmed by fluorescence titration. This probe had high sensitivity and specificity for the detection of lead ions. The fluorescence intensity of this probe was linear with respect to lead concentration over a range 0.3-2.1 nM (R(2) = 0.99). The limit of detection for lead ions was 0.1 nM at a signal-to-noise ratio of 3.
一种基于铽的荧光探针是通过将铽离子与设计的寡核苷酸（5'-ATATGGGGGATAT-3'，称为 GH5）配位合成的。GH5 将铽离子的荧光增强了四个数量级。不同寡核苷酸序列对铽离子的荧光增强表明发夹 GH5 的多鸟嘌呤环是增强铽离子发射的关键。Tb-GH5 探针的量子产率为 10.5%，并且该探针具有光稳定性。电导率滴定的结果表明，探针的化学计量比为 3.5 Tb：1 GH5，这通过荧光滴定得到了证实。该探针对铅离子的检测具有高灵敏度和特异性。该探针的荧光强度与铅浓度在 0.3-2.1 nM 范围内呈线性关系（R(2) = 0.99）。在信噪比为 3 时，铅离子的检测限为 0.1 nM。
