9,10-二苯基蒽衍生物的制备及对铜离子上、下转换检测研究

Cu2+是人体正常代谢所必需的微量元素之一，但是过量的Cu2+会造成代谢紊乱，进而诱发各种疾病。长期以来，铜材料的过度使用和后处理不当导致生活环境中的Cu2+浓度超标，成为重金属污染物之一，因此生活环境中Cu2+含量的检测成为人们关注的热点。基于荧光探针的荧光光谱法由于选择性好、灵敏度高等优点被广泛应用于离子检测领域。利用荧光探针分子与待检测离子可发生选择性的弱相互作用，研究者们探索并设计了诸多可用于Cu2+检测的荧光探针。然而普通的荧光探针由于灵敏度较差或选择性不理想等问题缺乏实际应用价值。设计并合成了一种新的化学型荧光探针分子9,10-二(3’-羟基-4’-亚甲胺氨基硫脲苯基)蒽（b-HTPA）。该探针分子通过与Cu2+的络合作用，改变自身的电子排布结构，使得其荧光性能发生显著变化，由此对Cu2+产生灵敏的响应。通过上、下转换荧光光谱来研究b-HTPA对Cu2+检测的各项性能，并结合拟合计算得出最终结果。选择性研究结果表明，相比其他13种金属阳离子，Cu2+对b-HTPA荧光猝灭效果最为显著，空白探针分子荧光与加入Cu2+后的荧光强度比可达150∶1。灵敏性研究结果表明，b-HTPA对Cu2+的最低检测限为2.78×10-7 mol·L-1，远低于中国卫生部《生活饮用水卫生标准》（GB5749-2006），表现出良好的荧光响应灵敏性和理想的最低检测限。响应时间测试结果表明，b-HTPA与Cu2+在0~2 min时间范围内反应速率最大，并在约10 min后反应完全，说明b-HTPA在对Cu2+检测中可以短时间产生响应，降低实际应用中的检测时间和周期。还使用八乙基卟啉钯（PdOEP）作为光敏剂，以b-HTPA为湮灭剂，利用上转换荧光光谱对b-HTPA/PdOEP/Cu2+体系的灵敏性和检测限进行测试研究。结果表明，探针的上转换荧光强度随着Cu2+浓度的增加而降低，具有良好的响应性，通过拟合计算，得出b-HTPA对Cu2+的检测限为3.78×10-6 mol·L-1，低于《生活饮用水卫生标准》规定的检测下限。设计合成的新型荧光探针分子9,10-二(3-羟基-4-亚甲胺氨基硫脲苯基)蒽对Cu2+具有高选择性、高灵敏度和理想的检测限，且响应速度快，展现了上转换发光在检测领域具有应用潜力。

Preparation of 9,10-Diphenylanthracene Derivative and Its Detection for Cu2+ by Up/Down-Conversion

Cu2+ is one of the essential trace elements for human metabolism, while excess ingestion will cause metabolic disorders even diseases. However, Cu2+ has been elevated levels in living environment due to overuse and inappropriate reprocessing measures of copper, which makes Cu2+ one of the toxic heavy metal pollutions. Therefore, the continuous concern over Cu2+ pollution has been a hot issue and attracted interest in the detection methods for Cu2+. Fluorescent spectrometry based on fluorescence probe has been widely used in ion detection field owing to good selectivity and high sensitivity. So far, researchers have developed fluorescence probes for Cu2+ detection based on selectional weak interaction between probe molecules and ions to be measured. However, these strategies all involve selectivity or sensitivity drawbacks, making the probes difficult for practical applications. Here, we designed and synthesized a new molecule 9,10-bis (3’-hydroxy-4’-thiosemicarbazide) phenylanthracene (b-HTPA) as a fluorescence probe for Cu2+ detection. The electron configuration of b-HTPA would change through coordinating with Cu2+, which would cause the remarkable change of fluorescence property of the b-HTPA as responsiveness for Cu2+. Characterizations of the detection of b-HTPA for Cu2+ were mainly carried out by down/up conversion fluorescence spectral. Results of selectivity research showed that Cu2+ has the strongest fluorescence quenching effect compared with the other thirteen kinds of metal cations. Besides, upon addition of Cu2+about 150-fold decreasement of fluorescence intensity was observed compared to other metal cations. The results indicated the good selectivity of b-HTPA to Cu2+. Results of sensitivity research showed that the detection limit of b-HTPA to Cu2+ was 2.78×10-7 mol·L-1 which was much lower than the hygienic standard for drinking water (GB5749-2006), which indicated high fluorescent response sensitivity and ideal detection limit. The results of response time test revealed that interaction rate between b-HTPA and Cu2+ was very high in the first two minutes and completely reacted within ten minutes, which showed that b-HTPA could be capable of reacting intensively with Cu2+ in short time which may save detection period. Moreover, up-conversion fluorescence spectra were also used for the sensitivity evaluation of b-HTPA to Cu2+ with palladium(Ⅱ) octaetylporphyrin (PdOEP)as the sensitizer. The research results showed that intensity of up-conversion fluorescence obviously declined upon the addition of Cu2+ and the detection limit was 3.78×10-6 mol·L-1 which is also lower than the hygienic standard. This work designed and synthesized the 9,10-bis (3’-hydroxy-4’-thiosemicarbazide) phenylanthracene as a fluorescence probe for Cu2+ detection, and the probe was proved to have highly selective and sensitive. Moreover, the probe b-HTPA had ideal detection limit and short detection period, which gave it great potential in the field of Cu2+ detection.