Das Diganta Kumar, Goswami Priyanka, Medhi Barnita
Department of Chemistry, Gauhati University, Guwahati, Assam, Pin 781 014, India,
J Fluoresc. 2014 May;24(3):689-93. doi: 10.1007/s10895-013-1338-z. Epub 2013 Dec 6.
Imbalance of zinc ion (Zn(2+)) in human body causes diseases like Alzheimer's and Parkinson's and therefore Zn(2+) estimation in biological fluids has diagnostic values. Fluorescence "off-on" sensors have advantages of high sensitivity and in situ application over other sensors. A new fluorescent "off-on" Zn(2+) sensor, N-benzoate-N' salicylaldehyde ethynelediamine (L), has been synthesisied. In 1:1(v/v) CH3OH:PBS (PBS = phosphate buffer solution), L shows ca. 20 times enhancement in fluorescence intensity on interaction with Zn(2+), due to snapping of photoinduced electron transfer (PET) process, which is selective over metal ions - Na(+), K(+), Ca(2+), Ni(2+), Cu(2+), Cd(2+), Hg(2+) and Pb(2+). These metal ions either individually or all together does not interfere the sensing ability of L towards Zn(2+). A 1:1 interaction between L and Zn(2+) ion with binding constant 10(4.25) has been established from spectroscopic data.
人体中锌离子（Zn(2+)）失衡会引发如阿尔茨海默病和帕金森病等疾病，因此在生物体液中估算Zn(2+)具有诊断价值。荧光“关-开”传感器相较于其他传感器具有高灵敏度和原位应用的优势。一种新型荧光“关-开”Zn(2+)传感器，N-苯甲酸-N'水杨醛乙二胺（L）已被合成。在1:1（v/v）的甲醇：磷酸盐缓冲溶液（PBS）中，L与Zn(2+)相互作用时荧光强度增强约20倍，这是由于光诱导电子转移（PET）过程的中断，它对金属离子——Na(+)、K(+)、Ca(2+)、Ni(2+)、Cu(2+)、Cd(2+)、Hg(2+)和Pb(2+)具有选择性。这些金属离子单独或一起都不会干扰L对Zn(2+)的传感能力。根据光谱数据确定了L与Zn(2+)离子之间为1:1的相互作用，结合常数为10(4.25) 。
