Tan Jin, Yan Xiu-Ping
Research Center for Analytical Sciences, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
Talanta. 2008 Jun 30;76(1):9-14. doi: 10.1016/j.talanta.2008.01.056. Epub 2008 Feb 6.
We report a simple twisted intramolecular charge transfer (TICT) chromogenic chemosensor for rapid and selective detection of Hg(2+) and Cu(2+). The sensor was composed of an electron-acceptor 4-fluoro moiety and an electron-donor 7-mercapto-2,1,3-benzoxadiazole species where the S together with the 1-N provided the soft binding unit. Upon Hg(2+) and Cu(2+) complexation, remarkable but different absorbance spectra shifts were obtained in CH(3)CN-H(2)O mixed buffer solution at pH 7.6, which can be easily used for naked-eye detection. The sensor formed a stable 2:1 complex with Cu(2+), and both 2:1 and 3:1 complexes with Hg(2+). While alkali-, alkaline earth- and other heavy and transition metal ions such as Na(+), Mg(2+), Mn(2+), Co(2+), Ni(2+), Ag(+), Zn(2+), Pb(2+) and Cd(2+) did not cause any significant spectral changes of the sensor. This finding is not only a supplement to the detecting methods for Hg(2+) and Cu(2+), but also adds new merits to the chemistry of 4,7-substituted 2,1,3-benzoxadiazoles.
我们报道了一种简单的扭曲分子内电荷转移（TICT）显色化学传感器，用于快速、选择性地检测Hg(2+)和Cu(2+)。该传感器由一个电子受体4-氟部分和一个电子供体7-巯基-2,1,3-苯并恶二唑组成，其中S与1-N一起提供了软结合单元。在Hg(2+)和Cu(2+)络合后，在pH 7.6的CH(3)CN-H(2)O混合缓冲溶液中获得了显著但不同的吸收光谱位移，这可很容易地用于肉眼检测。该传感器与Cu(2+)形成稳定的2:1络合物，与Hg(2+)形成2:1和3:1络合物。而碱金属、碱土金属以及其他重金属和过渡金属离子，如Na(+)、Mg(2+)、Mn(2+)、Co(2+)、Ni(2+)、Ag(+)、Zn(2+)、Pb(2+)和Cd(2+)，不会引起该传感器的任何显著光谱变化。这一发现不仅是对Hg(2+)和Cu(2+)检测方法的补充，也为4,7-取代的2,1,3-苯并恶二唑化学增添了新的优点。
