Department of Chemistry, The University of Burdwan, Golapbag, Burdwan, India.
Analyst. 2011 Nov 21;136(22):4839-45. doi: 10.1039/c1an15609h. Epub 2011 Oct 4.
A novel 6-(2-pyridinyl)-5,6-dihydrobenzimidazo[1,2-c]quinazoline (HL) serves as a first-time highly selective and sensitive ratiometric fluorescent chemosensor probe for oxorhenium (ReO(V)) ion in acetonitrile : water = 9 : 1 (v/v) at 25 °C. The decrease in fluorescence at 410 nm and increase in fluorescence at 478 nm with an isoemissive point at 444 nm in the presence of ReO(V) ion is accounted for by the formation of mononuclear [ReOL(2)Cl] complex, characterized by physico-chemical and spectroscopic tools. The fluorescence quantum yield of the chemosensor (HL) was only 0.198 at 410 nm, and it increased more than 3-fold in the presence of 2 equiv. of the ReO(V) ion at 478 nm. Interestingly, the introduction of other metal ions and relevant anions caused the fluorescence intensity at 478 nm to be either unchanged or weakened. The fluorescence-response fits a Hill coefficient of 2.088 indicates the formation of a 1 : 2 stoichiometry for the L-ReO(V) complex. In the concentration range of 0-20 μM of oxorhenium(V) species calibration graph was linear with correlation coefficient (R) of 0.99994 and the calibration sensitivity was found to be 4.0 × 10(-7) M. The cellular image in the confocal microscope clearly indicated the presence of ReO(V) in Candida albicans cells using this chemosensor (HL).
一种新型的 6-(2-吡啶基)-5,6-二氢苯并咪唑并[1,2-c]喹唑啉（HL），作为首次用于高选择性和高灵敏度比率荧光化学传感器探针，可在 25°C 的乙腈：水=9：1（v/v）中检测铼(V)离子。在存在 ReO(V)离子时，410nm 处的荧光强度降低，478nm 处的荧光强度增加，等发射点为 444nm，这是由于形成单核[ReOL(2)Cl]配合物所致，该配合物通过物理化学和光谱工具进行了表征。化学传感器（HL）在 410nm 处的荧光量子产率仅为 0.198，而在存在 2 当量 ReO(V)离子时，在 478nm 处增加了 3 倍以上。有趣的是，引入其他金属离子和相关阴离子会导致 478nm 处的荧光强度不变或减弱。荧光响应符合 Hill 系数为 2.088，表明 L-ReO(V)配合物的形成是 1：2 的化学计量比。在氧化铼(V)物种的浓度范围为 0-20μM 时，校准曲线呈线性，相关系数（R）为 0.99994，校准灵敏度为 4.0×10(-7)M。共聚焦显微镜中的细胞图像清楚地表明，使用这种化学传感器（HL）在白色念珠菌细胞中存在 ReO(V)。
