Wang Linlin, Song Jing, Liu Shaopu, Hao Chenxia, Kuang Nianxi, He Youqiu
School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
J Colloid Interface Sci. 2015 Nov 1;457:162-8. doi: 10.1016/j.jcis.2015.07.011. Epub 2015 Jul 7.
Even though various strategies have reported for DNA detection, development of a simple, time-saving and specific fluorescent sensing platform still remains a desired goal. In this work, a quantum dots (QDs) based fluorescent reversible "off-on" mode was developed for sensitively recognition of herring sperm DNA (hsDNA). Firstly, in the "turn off" stage, the fluorescence of glutathione (GSH) capped CdTe QDs could be effectively quenched by ytterbium ion (Yb(3+)) was due to the occurrence of the electron transfer between Yb(3+) and the photoexcited QDs. And then, in the following "turn on" stage, with the effective binding reaction of Yb(3+) to hsDNA, the fluorescence intensity of GSH-capped CdTe QDs enhanced. Under the optimal conditions, the linear range of fluorescence versus the concentration of hsDNA was 0.010-12 μg/mL, and the detection limit was 3.033 ng/mL. In addition, the reaction mechanism among GSH-capped CdTe QDs, Yb(3+) and hsDNA were investigated by fluorescence spectroscopy, UV-vis spectrophotometry, fluorescence lifetime measurement and viscosity measurements. This analytical fluorescent reversible "off-on" pattern offered a way with good sensitivity and selectivity for the detection of hsDNA.
尽管已经报道了多种用于DNA检测的策略，但开发一种简单、省时且特异性的荧光传感平台仍然是一个理想的目标。在这项工作中，开发了一种基于量子点（QDs）的荧光可逆“关-开”模式，用于灵敏识别鲱鱼精DNA（hsDNA）。首先，在“关闭”阶段，谷胱甘肽（GSH）包覆的CdTe量子点的荧光可被镱离子（Yb(3+)）有效淬灭，这是由于Yb(3+)与光激发的量子点之间发生了电子转移。然后，在随后的“开启”阶段，随着Yb(3+)与hsDNA的有效结合反应，GSH包覆的CdTe量子点的荧光强度增强。在最佳条件下，荧光强度与hsDNA浓度的线性范围为0.010 - 12 μg/mL，检测限为3.033 ng/mL。此外，通过荧光光谱、紫外-可见分光光度法、荧光寿命测量和粘度测量研究了GSH包覆的CdTe量子点、Yb(3+)和hsDNA之间的反应机理。这种分析性荧光可逆“关-开”模式为hsDNA的检测提供了一种具有良好灵敏度和选择性的方法。
